WorldWideScience

Sample records for steel girder bridges

  1. Comparative Research of Extra-large-span Cable-stayed Bridge with Steel Truss Girder and Steel Box Girder

    Directory of Open Access Journals (Sweden)

    Tan Manjiang

    2015-01-01

    Full Text Available To research structural performance of extra-large-span cable-stayed bridge under different section forms, with the engineering background of a 800m main-span cable-stayed bridge with steel truss girder, the cable-stayed bridge with steel box girder is designed according to the current bridge regulations when two bridges are designed in an ultimate state of the carrying capacity, so the maximum stress and minimum stress of the stress envelope diagram are substantially the same. A comprehensive comparison is given to two types of bridge on the aspect of static force, natural vibration frequency, stability, economic performance and so on. Analysis results provide future reference for the large-span cable-stayed bridge to select between the steel truss girder and the steel box girder.

  2. Bridge maintenance to enhance corrosion resistance and performance of steel girder bridges

    Science.gov (United States)

    Moran Yanez, Luis M.

    The integrity and efficiency of any national highway system relies on the condition of the various components. Bridges are fundamental elements of a highway system, representing an important investment and a strategic link that facilitates the transport of persons and goods. The cost to rehabilitate or replace a highway bridge represents an important expenditure to the owner, who needs to evaluate the correct time to assume that cost. Among the several factors that affect the condition of steel highway bridges, corrosion is identified as the main problem. In the USA corrosion is the primary cause of structurally deficient steel bridges. The benefit of regular high-pressure superstructure washing and spot painting were evaluated as effective maintenance activities to reduce the corrosion process. The effectiveness of steel girder washing was assessed by developing models of corrosion deterioration of composite steel girders and analyzing steel coupons at the laboratory under atmospheric corrosion for two alternatives: when high-pressure washing was performed and when washing was not considered. The effectiveness of spot painting was assessed by analyzing the corrosion on steel coupons, with small damages, unprotected and protected by spot painting. A parametric analysis of corroded steel girder bridges was considered. The emphasis was focused on the parametric analyses of corroded steel girder bridges under two alternatives: (a) when steel bridge girder washing is performed according to a particular frequency, and (b) when no bridge washing is performed to the girders. The reduction of structural capacity was observed for both alternatives along the structure service life, estimated at 100 years. An economic analysis, using the Life-Cycle Cost Analysis method, demonstrated that it is more cost-effective to perform steel girder washing as a scheduled maintenance activity in contrast to the no washing alternative.

  3. Effects of Adhesive Connection on Composite Action between FRP Bridge Deck and Steel Girder

    NARCIS (Netherlands)

    Jiang, X.; Luo, Chengwei; Qiang, X.; Kolstein, M.H.; Bijlaard, F.S.K.

    2017-01-01

    The FRP-steel girder composite bridge system is increasingly used in new constructions of bridges as well as rehabilitation of old bridges. However, the understanding of composite action between FRP decks and steel girders is limited and needs to be systematically investigated. In this paper,

  4. Effects of Adhesive Connection on Composite Action between FRP Bridge Deck and Steel Girder

    Directory of Open Access Journals (Sweden)

    Xu Jiang

    2017-01-01

    Full Text Available The FRP-steel girder composite bridge system is increasingly used in new constructions of bridges as well as rehabilitation of old bridges. However, the understanding of composite action between FRP decks and steel girders is limited and needs to be systematically investigated. In this paper, depending on the experimental investigations of FRP to steel girder system, the Finite Element (FE models on experiments were developed and analyzed. Comparison between experiments and FE results indicated that the FE models were much stiffer for in-plane shear stiffness of the FRP deck panel. To modify the FE models, rotational spring elements were added between webs and flanges of FRP decks, to simulate the semirigid connections. Numerical analyses were also conducted on four-point bending experiments of FRP-steel composite girders. Good agreement between experimental results and FE analysis was achieved by comparing the load-deflection curves at midspan and contribution of composite action from FRP decks. With the validated FE models, the parametric studies were conducted on adhesively bonded connection between FRP decks and steel girders, which indicated that the loading transfer capacity of adhesive connection was not simply dependent on the shear modulus or thickness of adhesive layer but dominated by the in-plane shear stiffness K.

  5. Shear Behavior of Corrugated Steel Webs in H Shape Bridge Girders

    Directory of Open Access Journals (Sweden)

    Qi Cao

    2015-01-01

    Full Text Available In bridge engineering, girders with corrugated steel webs have shown good mechanical properties. With the promotion of composite bridge with corrugated steel webs, in particular steel-concrete composite girder bridge with corrugated steel webs, it is necessary to study the shear performance and buckling of the corrugated webs. In this research, by conducting experiment incorporated with finite element analysis, the stability of H shape beam welded with corrugated webs was tested and three failure modes were observed. Structural data including load-deflection, load-strain, and shear capacity of tested beam specimens were collected and compared with FEM analytical results by ANSYS software. The effects of web thickness, corrugation, and stiffening on shear capacity of corrugated webs were further discussed.

  6. Microstructural characterisation and corrosion performance of old railway girder bridge steel and modern weathering structural steel

    International Nuclear Information System (INIS)

    Tewary, N.K.; Kundu, A.; Nandi, R.; Saha, J.K.; Ghosh, S.K.

    2016-01-01

    Highlights: • Microstructure and corrosion performance are compared for two structural steels. • Microstructure evolution shows primarily ferrite-pearlite in both the steels. • Steels show higher corrosion rate in 1% HCl solution than in 3.5% NaCl solution. • The corrosion products show the presence of oxide, hydroxide and oxy-hydroxides. • The corroded surface reveals morphologies like flowery, cotton balls and rosette. - Abstract: A comparison on microstructure and corrosion performance has been made between the two structural steels used in old railway girder bridge (Sample A) and modern grades of weathering structural steel (Sample B). The microstructures, viewed under optical microscope and scanning electron microscope (SEM), show mainly ferrite-pearlite phase constituents in both the steels, A and B. The phase fraction analysis shows higher amount of pearlite in steel A compared to that of steel B. The grain size of steel A is larger than that of steel B under identical processing condition. The immersion corrosion test in 3.5% NaCl shows that the corrosion rate of steel A increases with time, while the same for steel B decreases with time. On the other hand, corrosion test in 1% HCl shows that the corrosion rate of both steel A and B is higher as compared to that of NaCl which always decreases with time. The XRD analysis of corrosion products show the presence of many oxides, hydroxide and oxy-hydroxide like Lepidocrocite (γ-FeOOH), Goethite (α-FeOOH), Akaganeite (β-FeOOH), Magnetite (Fe_3O_4) and Maghemite (γ-Fe_2O_3) in both the steels. The SEM images of corroded surfaces reveal different morphologies like flowery, cotton balls and rosette etc. which indicate that the corrosion products primarily contain Lepidocrocite (γ-FeOOH), Goethite (α-FeOOH) and Akaganeite (β-FeOOH).

  7. Prediction of welding shrinkage deformation of bridge steel box girder based on wavelet neural network

    Science.gov (United States)

    Tao, Yulong; Miao, Yunshui; Han, Jiaqi; Yan, Feiyun

    2018-05-01

    Aiming at the low accuracy of traditional forecasting methods such as linear regression method, this paper presents a prediction method for predicting the relationship between bridge steel box girder and its displacement with wavelet neural network. Compared with traditional forecasting methods, this scheme has better local characteristics and learning ability, which greatly improves the prediction ability of deformation. Through analysis of the instance and found that after compared with the traditional prediction method based on wavelet neural network, the rigid beam deformation prediction accuracy is higher, and is superior to the BP neural network prediction results, conform to the actual demand of engineering design.

  8. Finite element model updating of multi-span steel-arch-steel-girder bridges based on ambient vibrations

    Science.gov (United States)

    Hou, Tsung-Chin; Gao, Wei-Yuan; Chang, Chia-Sheng; Zhu, Guan-Rong; Su, Yu-Min

    2017-04-01

    The three-span steel-arch-steel-girder Jiaxian Bridge was newly constructed in 2010 to replace the former one that has been destroyed by Typhoon Sinlaku (2008, Taiwan). It was designed and built to continue the domestic service requirement, as well as to improve the tourism business of the Kaohsiung city government, Taiwan. This study aimed at establishing the baseline model of Jiaxian Bridge for hazardous scenario simulation such as typhoons, floods and earthquakes. Necessities of these precaution works were attributed to the inherent vulnerability of the sites: near fault and river cross. The uncalibrated baseline bridge model was built with structural finite element in accordance with the blueprints. Ambient vibration measurements were performed repeatedly to acquire the elastic dynamic characteristics of the bridge structure. Two frequency domain system identification algorithms were employed to extract the measured operational modal parameters. Modal shapes, frequencies, and modal assurance criteria (MAC) were configured as the fitting targets so as to calibrate/update the structural parameters of the baseline model. It has been recognized that different types of structural parameters contribute distinguishably to the fitting targets, as this study has similarly explored. For steel-arch-steel-girder bridges in particular this case, joint rigidity of the steel components was found to be dominant while material properties and section geometries relatively minor. The updated model was capable of providing more rational elastic responses of the bridge superstructure under normal service conditions as well as hazardous scenarios, and can be used for manage the health conditions of the bridge structure.

  9. Research on structural dynamic characteristics of continuous steel box girder-bridge with lager ratio of wide-span

    Directory of Open Access Journals (Sweden)

    Yin Haijun

    2018-01-01

    Full Text Available Structure natural frequency and mode of vibration can not only reflect the structure modal parameters of dynamic properties, but also incarnate the dynamic evaluation characteristics of bridge structure. This paper applies ANSYS to establish the finite element model based on a continuous steel box girder bridge in order to obtain the corresponding modal analysis parameters. Through the environmental stimulation test, The results show that height of the steel box girder and the setting of diaphragm plate is reasonable, transverse space of piers not merely provide enough support but also ensure lateral stability of the bridge, as well as offering aside the maximum lateral clearance of the existing road. Meanwhile, the calculation results have important engineering practical values. which can provide basic data for the design, construction and maintenance of similar Bridges.

  10. Shear evaluation of tapered bridge girder panels with steel corrugated webs near the supports of continuous bridges

    OpenAIRE

    Zevallos, E.; Hassanein, M.F.; Real Saladrigas, Esther; Mirambell Arrizabalaga, Enrique

    2016-01-01

    Because of public construction budgets were cut over the last few years, new bridge girders with corrugated webs to reduce the construction costs have become more widely studied and used. In spite that tapered bridge girders with corrugated webs (BGCWs) are used in modern bridges, their shear strength and behaviour rarely exists in literature. Based on available literature, the web of the linearly tapered BGCWs may be divided into three typologies with different structural response to shear f...

  11. Wireless ultrasonic wavefield imaging via laser for hidden damage detection inside a steel box girder bridge

    International Nuclear Information System (INIS)

    An, Yun-Kyu; Song, Homin; Sohn, Hoon

    2014-01-01

    This paper presents a wireless ultrasonic wavefield imaging (WUWI) technique for detecting hidden damage inside a steel box girder bridge. The proposed technique allows (1) complete wireless excitation of piezoelectric transducers and noncontact sensing of the corresponding responses using laser beams, (2) autonomous damage visualization without comparing against baseline data previously accumulated from the pristine condition of a target structure and (3) robust damage diagnosis even for real structures with complex structural geometries. First, a new WUWI hardware system was developed by integrating optoelectronic-based signal transmitting and receiving devices and a scanning laser Doppler vibrometer. Next, a damage visualization algorithm, self-referencing f-k filter (SRF), was introduced to isolate and visualize only crack-induced ultrasonic modes from measured ultrasonic wavefield images. Finally, the performance of the proposed technique was validated through hidden crack visualization at a decommissioned Ramp-G Bridge in South Korea. The experimental results reveal that the proposed technique instantaneously detects and successfully visualizes hidden cracks even in the complex structure of a real bridge. (paper)

  12. PARAMETRIC STUDY OF SKEW ANGLE ON BOX GIRDER BRIDGE DECK

    OpenAIRE

    Shrikant D. Bobade *, Dr. Valsson Varghese

    2016-01-01

    Box girder bridge deck, is the most common type of bridges in world and India, it consists of several Slab or girders. The span in the direction of the roadway and connected across their tops and bottoms by a thin continuous structural stab, the longitudinal box girders can be made of steel or concrete. The Simple supported single span concrete bridge deck is presented in present study. Skewed bridges are suitable in highway design when the geometry of straight bridges is not possible. The sk...

  13. Development of bridge girder movement criteria for accelerated bridge construction.

    Science.gov (United States)

    2014-06-01

    End diaphragms connect multiple girders to form a bridge superstructure system for effective resistance to earthquake loads. Concrete : girder bridges that include end diaphragms consistently proved to perform well during previous earthquake events. ...

  14. Shear capacity of in service prestressed concrete bridge girders.

    Science.gov (United States)

    2010-05-17

    The design of prestressed concrete bridge girders has changed significantly over the past several : decades. Specifically, the design procedure to calculate the shear capacity of bridge girders that : was used forty years ago is very different than t...

  15. Implementation of straight and curved steel girder erection design tools construction : summary.

    Science.gov (United States)

    2010-11-05

    Project 0-5574 Curved Plate Girder Design for Safe and Economical Construction, resulted in the : development of two design tools, UT Lift and UT Bridge. UT Lift is a spreadsheet-based program for analyzing : steel girders during lifting while ...

  16. Design aids of NU I-girders bridges.

    Science.gov (United States)

    2010-05-01

    Precast prestressed concrete I-Girder bridges have become the most dominant bridge system in the United States. In the early design : stages, preliminary design becomes a vital first step in designing an economical bridge. Within the state of Nebrask...

  17. The Vibration Based Fatigue Damage Assessment of Steel and Steel Fiber Reinforced Concrete (SFRC Composite Girder

    Directory of Open Access Journals (Sweden)

    Xu Chen

    2015-01-01

    Full Text Available The steel-concrete composite girder has been usually applied in the bridge and building structures, mostly consisting of concrete slab, steel girder, and shear connector. The current fatigue damage assessment for the composite girder is largely based on the strain values and concrete crack features, which is time consuming and not stable. Hence the vibration-based fatigue damage assessment has been considered in this study. In detail, a steel-steel fiber reinforced concrete (SFRC composite girder was tested. The steel fiber reinforced concrete is usually considered for dealing with the concrete cracks in engineering practice. The composite girder was 3.3m long and 0.45m high. The fatigue load and impact excitation were applied on the specimen sequentially. According to the test results, the concrete crack development and global stiffness degradation during the fatigue test were relatively slow due to the favourable performance of SFRC in tension. But on the other hand, the vibration features varied significantly during the fatigue damage development. Generally, it confirmed the feasibility of executing fatigue damage assessment of composite bridge based on vibration method.

  18. Load Distribution Factors for Composite Multicell Box Girder Bridges

    Science.gov (United States)

    Tiwari, Sanjay; Bhargava, Pradeep

    2017-12-01

    Cellular steel section composite with a concrete deck is one of the most suitable superstructures in resisting torsional and warping effects induced by highway loading. This type of structure has inherently created new design problems for engineers in estimating its load distribution when subjected to moving vehicles. Indian Codes of Practice does not provide any specific guidelines for the design of straight composite concrete deck-steel multi-cell bridges. To meet the practical requirements arising during the design process, a simple design method is needed for straight composite multi-cell bridges in the form of load distribution factors for moment and shear. This work presents load distribution characteristics of straight composite multi-cell box girder bridges under IRC trains of loads.

  19. Suspension Bridge Flutter for Girder with Separate Control Flaps

    DEFF Research Database (Denmark)

    Huynh, T.; Thoft-Christensen, Palle

    Active vibration control of long span suspension bridge flutter using separated control flaps (SFSC) has shown to increase effectively the critical wind speed of bridges. In this paper, an SFSC calculation based on modal equations of the vertical and torsional motions of the bridge girder including...... the flaps is presented. The length of the flaps attached to the girder, the flap configuration and the flap rotational angles are parameters used to increase the critical wind speed of the bridge. To illustrate the theory a numerical example is shown for a suspension bridge of 1000m+2500m+1000m span based...... on the Great Belt Bridge streamlined girder....

  20. The effect of span length and girder type on bridge costs

    Directory of Open Access Journals (Sweden)

    Batikha Mustafa

    2017-01-01

    Full Text Available Bridges have an important role in impacting the civilization, growth and economy of cities from ancient time until these days due to their function in reducing transportation cost and time. Therefore, development of bridges has been a knowledge domain in civil engineering studies in terms of their types and construction materials to confirm a reliable, safe, economic design and construction. Girder-bridge of concrete deck and I-beam girder has been used widely for short and medium span bridges because of ease and low-cost of fabrication. However, many theoretical and practical investigations are still undertaken regarding the type of beam girder; i.e steel composite or prestressed concrete. This paper evaluates the effect of bridge span and the type of girder on the capital cost and life cycle costs of bridges. Three types of girders were investigated in this research: steel composite, pre-tensioned pre-stressed concrete and post-tensioned pre-stressed concrete. The structural design was analyzed for 5 span lengths: 20, 25, 30, 35 and 40m. Then, the capital construction cost was accounted for 15 bridges according to each span and construction materials. Moreover, the maintenance required for 50 years of bridge life was evaluated and built up as whole life costs for each bridge. As a result of this study, the influence of both span length and type of girder on initial construction cost and maintenance whole life costs were assessed to support the decision makers and designers in the selection process for the optimum solution of girder bridges.

  1. Continuity diaphragm for skewed continuous span precast prestressed concrete girder bridges : technical summary report.

    Science.gov (United States)

    2004-03-01

    Most highway bridges are built as cast-in-place : reinforced concrete slabs and prestressed concrete : girders. The shear connectors on the top of the girders : assure composite action between the slabs and : girders. The design guidelines for bridge...

  2. Self-Consolidating Concrete for Prestressed Bridge Girders

    Science.gov (United States)

    2017-07-01

    This document reports the findings of a research project designed to better understand material and structural performance of prestressed bridge girders made with Self-Consolidating Concrete (SCC) from Wisconsin. SCC has high potential to be used for...

  3. Self-Consolidating Concrete for Prestressed Bridge Girders : Research Brief

    Science.gov (United States)

    2017-08-01

    Self-consolidating concrete (SCC) is commonly used as an alternative to conventional concrete (CC) in precast, prestressed concrete (PSC) bridge girders. The high strength, highly workable mixture can flow through dense reinforcement to fill formwork...

  4. SEISMIC BEHAVIOR OF STEEL MONORAIL BRIDGES UNDER TRAIN LOAD DURING STRONG EARTHQUAKES

    OpenAIRE

    KIM, C. W.; KAWATANI, M.; KANBARA, T.; NISHIMURA, N.

    2013-01-01

    This paper investigated dynamic responses of steel monorail bridges incorporating train-bridge interaction under strong earthquakes. Two types of steel monorail bridges were considered in the study: a conventional type with steel track-girder; an advanced type with composite track-girder and simplified lateral bracing system. During strong earthquakes, monorail train was assumed standing on the track-girder of monorail bridges. Observations through the analytical study showed that considering...

  5. Evaluation on Impact Interaction between Abutment and Steel Girder Subjected to Nonuniform Seismic Excitation

    Directory of Open Access Journals (Sweden)

    Yue Zheng

    2015-01-01

    Full Text Available This paper aims to evaluate the impact interaction between the abutment and the girder subjected to nonuniform seismic excitation. An impact model based on tests is presented by taking material properties of the backfill of the abutment into consideration. The conditional simulation is performed to investigate the spatial variation of earthquake ground motions. A two-span continuous steel box girder bridge is taken as the example to analyze and assess the pounding interaction between the abutment and the girder. The detailed nonlinear finite element (FE model is established and the steel girder and the reinforced concrete piers are modeled by nonlinear fiber elements. The pounding element of the abutment is simulated by using a trilinear compression gap element. The elastic-perfectly plastic element is used to model the nonlinear rubber bearings. The comparisons of the pounding forces, the shear forces of the nonlinear bearings, the moments of reinforced concrete piers, and the axial pounding stresses of the steel girder are studied. The made observations indicate that the nonuniform excitation for multisupport bridge is imperative in the analysis and evaluation of the pounding effects of the bridges.

  6. Proposal and study of a long-span composite cable-stayed bridge with new hybrid girder; Atarashii gosei kozo shuketa wo mochiita chodai fukugo shachokyo no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, K.; Hishiki, Y.; Furuichi, K. [Kajima Corp., Tokyo (Japan)

    1999-09-30

    A hybrid or mixed structure (composite structures) are a matter of increasing concern which takes in each advantage of steel and concrete. A field of bridges is no exception, with the plan and construction carried out for the new type of composite bridge, such as a composite cable-stayed bridge and a composite extra dose bridge as a long span bridge, and a composite truss bridge and a corrugated steel plate web bridge as a medium-span bridge, with technological development becoming active in this field. In such a technological trend, a hybrid two-girder structure was devised, a structure consisting of a concrete filled steel pipe for a girder and a precast (PC) floor plate for a floor board, as the girder structure of a long-span cable-stayed bridge in the subject research; also, applicability was examined using, as an example, the composite cable-stayed bridge with hybrid girders employed for the span. This paper reports the result of the analysis of the entire system, the analysis made for the purpose of examining the characteristic and the feasibility of this hybrid girder. The analysis revealed the structural feasibility of the long-span composite cable-stayed bridge using two hybrid girders of concrete-filled steel pipes thus devised. (NEDO)

  7. Extension of POA based on Fiber Element to Girder Bridge

    International Nuclear Information System (INIS)

    Li Zhenxin; Qiang Shizhong

    2010-01-01

    Because of its main advantage of simplicity, practicality, lower computational cost and relative good results Pushover analysis (POA) has become an effective analytical tool during the last decade for the seismic assessment of buildings. But such work on bridges has been very limited. Hence, the aim of this study is to adapt POA for nonlinear seismic analysis of girder bridges, and investigate its applicability in the case of an existing river-spanning approach bridge. To three different types bridge models the nonlinear POA, which adopts fiber model nonlinear beam-column element based on flexibility approach, with return period about 2500 years is carried out. It can be concluded that POA is applicable for bridges, with some shortcomings associated with the method in general, even when it is applied for buildings. Finally the applicable selection for monitoring point and lateral load pattern is suggested according to dynamic characteristic of girder bridges.

  8. Development of Embedded EM Sensors for Estimating Tensile Forces of PSC Girder Bridges

    Science.gov (United States)

    Kim, Ju-Won; Lee, Chaggil; Park, Seunghee

    2017-01-01

    The tensile force of pre-stressed concrete (PSC) girders is the most important factor for managing the stability of PSC bridges. The tensile force is induced using pre-stressing (PS) tendons of a PSC girder. Because the PS tendons are located inside of the PSC girder, the tensile force cannot be measured after construction using conventional NDT (non-destructive testing) methods. To monitor the induced tensile force of a PSC girder, an embedded EM (elasto-magnetic) sensor was proposed in this study. The PS tendons are made of carbon steel, a ferromagnetic material. The magnetic properties of the ferromagnetic specimen are changed according to the induced magnetic field, temperature, and induced stress. Thus, the tensile force of PS tendons can be estimated by measuring their magnetic properties. The EM sensor can measure the magnetic properties of ferromagnetic materials in the form of a B (magnetic density)-H (magnetic force) loop. To measure the B-H loop of a PS tendon in a PSC girder, the EM sensor should be embedded into the PSC girder. The proposed embedded EM sensor can be embedded into a PSC girder as a sheath joint by designing screw threads to connect with the sheath. To confirm the proposed embedded EM sensors, the experimental study was performed using a down-scaled PSC girder model. Two specimens were constructed with embedded EM sensors, and three sensors were installed in each specimen. The embedded EM sensor could measure the B-H loop of PS tendons even if it was located inside concrete, and the area of the B-H loop was proportionally decreased according to the increase in tensile force. According to the results, the proposed method can be used to estimate the tensile force of unrevealed PS tendons. PMID:28867790

  9. Study on the Old Girders in the Widening Hollow Slab Girder Bridge

    Science.gov (United States)

    Wang, Ying; Zhang, Li Fang; Ma, Hai Yan

    2018-06-01

    Taking the bridge widening project of Shanghai-Hangzhou-Ningbo expressway widening construction project (China) as the background in this paper, the variation law of the internal force of the old bridge in the widening hollow slab girder bridge under vehicle load is studied, which is under the condition of different span lengths and different widening widths. Three different span lengths of the pre-tensioned prestressed hollow slab girder bridges are selected, the spatial finite element models of both the old bridge and the whole structure of widening bridge are established and calculated respectively by Midas/Civil software. The influences of widening and load increasing on the old bridges under the vehicle load are compared and analyzed. In addition, the authors also analyze the influences of different widening widths on the force state of old bridges under the condition of widening the same number of lane. Moreover , the effects on the old bridges that are caused by the uneven foundation settlement of widening bridge structure are also studied in this paper. This paper can provide some references for widening design of hollow slab bridges.

  10. Life-Cycle Monitoring of Long-Span PSC Box Girder Bridges through Distributed Sensor Network: Strategies, Methods, and Applications

    OpenAIRE

    Chen, Zheheng; Guo, Tong; Yan, Shengyou

    2015-01-01

    Structural health monitoring (SHM) has attracted much attention in recent years, which enables early warnings of structural failure, condition assessments, and rational maintenance/repair strategies. In the context of bridges, many long-span steel bridges in China have been installed with the SHM systems; however, the applications of the SHM in prestressed concrete (PSC) bridges are still rather limited. On the other hand, the PSC box girder bridges are extensively used in highway and railway...

  11. Simulation Study on Train-Induced Vibration Control of a Long-Span Steel Truss Girder Bridge by Tuned Mass Dampers

    Directory of Open Access Journals (Sweden)

    Hao Wang

    2014-01-01

    Full Text Available Train-induced vibration of steel truss bridges is one of the key issues in bridge engineering. This paper talks about the application of tuned mass damper (TMD on the vibration control of a steel truss bridge subjected to dynamic train loads. The Nanjing Yangtze River Bridge (NYRB is taken as the research object and a recorded typical train load is included in this study. With dynamic finite element (FE method, the real-time dynamic responses of NYRB are analyzed based on a simplified train-bridge time-varying system. Thereinto, two cases including single train moving at one side and two trains moving oppositely are specifically investigated. According to the dynamic characteristics and dynamic responses of NYRB, the fourth vertical bending mode is selected as the control target and the parameter sensitivity analysis on vibration control efficiency with TMD is conducted. Using the first-order optimization method, the optimal parameters of TMD are then acquired with the control efficiency of TMD, the static displacement of Midspan, expenditure of TMDs, and manufacture difficulty of the damper considered. Results obtained in this study can provide references for the vibration control of steel truss bridges.

  12. Shear in high strength concrete bridge girders : technical report.

    Science.gov (United States)

    2013-04-01

    Prestressed Concrete (PC) I-girders are used extensively as the primary superstructure components in Texas highway bridges. : A simple semi-empirical equation was developed at the University of Houston (UH) to predict the shear strength of PC I-girde...

  13. Design and construction of a cable-stayed composite girder bridge with precast RC-slabs; Purekyasuto shohan gosei keta shachokoyo no sekkei to seko

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, K. [Tokyo Metropolitan Univ. (Japan). Faculty of Technology; Shimura, T.; Tachibana, Y.; Echigo, S. [Kawada Industries Inc., Tokyo (Japan)

    1995-09-20

    A report on design and execution of cable-stayed composite girder bridge with precast RC-slabs constructed first in Japan though in small scale was described. This bridge adopted steel slabs relatively low in slab height for main slab and with two boxes slab section, and was designed at an aim of being more economic and shorter in its working term in comparison with steel girder slab type, on a base of the design in a region allowable with the existing design standards. This bridge is mainly in accordance with the regulation on continuous bridge in the prescription of road bridge, and is designed for normal RC-girder selecting between girder supports to direction normal to bridge axis as usual without using specially strong concrete to the girder. And, in order to fill with the regulation on allowable tensile stress on considering effects of creep and drying shrinkage, a method adding prestress to the slabs was adopted. Furthermore, a loop-like overlap joint for cable joint for the precast girders, expansion concrete for joint portion to compose the girder with the steel slab and so forth were adopted. 12 refs., 22 figs., 5 tabs.

  14. Evaluation of a highway bridge constructed using high strength lightweight concrete bridge girders.

    Science.gov (United States)

    2011-04-01

    The use of high performance concretes to provide longer bridge spans has been limited due to the capacity of existing infrastructure to handle the load of the girders during transportation. The use of High Strength Lightweight Concrete (HSLW) can pro...

  15. Repair of Impact-Damaged Prestressed Bridge Girders Using Strand Splices and Fabric Reinforced Cementitious Matrix

    OpenAIRE

    Jones, Mark Stevens

    2017-01-01

    This thesis investigates the repair of impact-damaged prestressed concrete bridge girders with strand splices and fabric-reinforced cementitious matrix systems, specifically for repair of structural damage to the underside of an overpass bridge girder due to an overheight vehicle collision. Collision damage to bridges can range from minor to catastrophic, potentially requiring repair or replacement of a bridge girder. This thesis investigates the performance of two different types of repair...

  16. Statistical determination of significant curved I-girder bridge seismic response parameters

    Science.gov (United States)

    Seo, Junwon

    2013-06-01

    Curved steel bridges are commonly used at interchanges in transportation networks and more of these structures continue to be designed and built in the United States. Though the use of these bridges continues to increase in locations that experience high seismicity, the effects of curvature and other parameters on their seismic behaviors have been neglected in current risk assessment tools. These tools can evaluate the seismic vulnerability of a transportation network using fragility curves. One critical component of fragility curve development for curved steel bridges is the completion of sensitivity analyses that help identify influential parameters related to their seismic response. In this study, an accessible inventory of existing curved steel girder bridges located primarily in the Mid-Atlantic United States (MAUS) was used to establish statistical characteristics used as inputs for a seismic sensitivity study. Critical seismic response quantities were captured using 3D nonlinear finite element models. Influential parameters from these quantities were identified using statistical tools that incorporate experimental Plackett-Burman Design (PBD), which included Pareto optimal plots and prediction profiler techniques. The findings revealed that the potential variation in the influential parameters included number of spans, radius of curvature, maximum span length, girder spacing, and cross-frame spacing. These parameters showed varying levels of influence on the critical bridge response.

  17. Flexural and Shear Behavior of FRP Strengthened AASHTO Type Concrete Bridge Girders

    Directory of Open Access Journals (Sweden)

    Nur Yazdani

    2016-01-01

    Full Text Available Fiber-reinforced polymers (FRP are being increasingly used for the repair and strengthening of deteriorated or unsafe concrete structures, including structurally deficient concrete highway bridges. The behavior of FRP strengthened concrete bridge girders, including failure modes, failure loads, and deflections, can be determined using an analytical finite element modeling approach, as outlined in this paper. The differences in flexural versus shear FRP strengthening and comparison with available design guidelines are also beneficial to design professionals. In this paper, a common AASHTO type prestressed concrete bridge girder with FRP wrapping was analyzed using the ANSYS FEM software and the ACI analytical approach. Both flexural and shear FRP applications, including vertical and inclined shear strengthening, were examined. Results showed that FRP wrapping can significantly benefit concrete bridge girders in terms of flexure/shear capacity increase, deflection reduction, and crack control. The FRP strength was underutilized in the section selected herein, which could be addressed through decrease of the amount of FRP and prestressing steel used, thereby increasing the section ductility. The ACI approach produced comparable results to the FEM and can be effectively and conveniently used in design.

  18. Analytical Calculation And FEM Analysis Main Girder Double Girder Bridge Crane

    Directory of Open Access Journals (Sweden)

    Muamer Delić

    2017-02-01

    Full Text Available The cranes are now not replaceable mode of transport of materials and finished products both in production halls and in the open space. This paper made the whole analytical calculation of double girder bridge cranes to be used in laboratories exclusively for testing, determined by the maximum bending stress and deflection of the main girder. After calculating the dimensions, we created a model cranes in software CATIA V5. The same model was subjected to FEM analysis of the same name software. At the end of the paper comparison has been done. The objective of the calculation and analysis of the model was to develop a model crane and to serve for the next tests. Dimensions of the crane are given according to the laboratory where it will be located.

  19. Condition Assessment of PCI Bridge Girder a Result of The Reduction Prestressing Force

    Directory of Open Access Journals (Sweden)

    Suangga Made

    2014-03-01

    Full Text Available PCI bridge girders is known and widely used for many construction e.g.: bridge, wharf, flyover, and other application. PC Bridge girders have two types: Pre - tensioned girders and post - tensioned girders. In pre tensioned girders, prestressing in carried out first then after that the fresh concrete poured. The prestressing process in only carried off after the concrete has sufficient strength. In this study, analysis was conducted for PCI bridge girder with span is 40 meters. Based on the data geometry bridge dimension girder, material girder, and material strands cable, it will be analyzed to calculate the natural frequencies and moment capacity using finite element program (Midas/Civil program. So it can be estimated how much the percentage reduction prestress force on the bridge until PCI bridge structure collapses. From the calculation, it found that the pattern comparison between reduction prestressing force and natural frequency are linear. These results are also similar for natural frequency versus moment capacity.PCI bridge will collapse when the reduction prestreesing force of 45 % to 50 % from the total loss of prestressing.

  20. review of elastic analys ew of elastic analysis of box girder bridges

    African Journals Online (AJOL)

    eobe

    Nigerian Journal of Technology,. Vol. 34, No. 1, January 2015 87 bridges under the attack of pitting corrosion. Savkovic et al. [130] proposed an optimum solution to optimization of the box section of the main girder of the bridge crane. Reduction of the girder mass was set as the objective function. Optimum dimensions of the.

  1. Continuity diaphragm for skewed continuous span precast prestressed concrete girder bridges.

    Science.gov (United States)

    2004-10-01

    Continuity diaphragms used on skewed bents in prestressed girder bridges cause difficulties in detailing and : construction. Details for bridges with large diaphragm skew angles (>30) have not been a problem for LA DOTD. : However, as the skew angl...

  2. Steel framing strategies for highly skewed bridges to reduce/eliminate distortion near skewed supports.

    Science.gov (United States)

    2014-05-01

    Different problems in straight skewed steel I-girder bridges are often associated with the methods used for detailing the cross-frames. Use of theoretical terms to describe these detailing methods and absence of complete and simplified design approac...

  3. Life-Cycle Monitoring of Long-Span PSC Box Girder Bridges through Distributed Sensor Network: Strategies, Methods, and Applications

    Directory of Open Access Journals (Sweden)

    Zheheng Chen

    2015-01-01

    Full Text Available Structural health monitoring (SHM has attracted much attention in recent years, which enables early warnings of structural failure, condition assessments, and rational maintenance/repair strategies. In the context of bridges, many long-span steel bridges in China have been installed with the SHM systems; however, the applications of the SHM in prestressed concrete (PSC bridges are still rather limited. On the other hand, the PSC box girder bridges are extensively used in highway and railway systems and premature damage of these bridges is often reported, resulting in considerable maintenance and/or replacement costs. First, this paper presents a state-of-art review on the SHM of long-span PSC bridges. Monitoring strategies, methods, and previous applications for these bridges are summarized and discussed. In order to well capture the behavior of the bridge during its whole life and to maximize the use of sensors, a life-cycle monitoring strategy is proposed, in which the sensor layout is determined according to requirements for construction monitoring, completion test, and in-service monitoring. A case study is made on a three-span PSC box girder bridge in China. The system configuration, sensor layout, and data communications, and so forth, are presented. The up-to-date monitored structural responses are analyzed and compared with the design values.

  4. Nonlinear Stability Analysis of a Composite Girder Cable-Stayed Bridge with Three Pylons during Construction

    Directory of Open Access Journals (Sweden)

    Xiaoguang Deng

    2015-01-01

    Full Text Available Based on the nonlinear stability analysis method, the 3D nonlinear finite element model of a composite girder cable-stayed bridge with three pylons is established to research the effect of factors including geometric nonlinearity, material nonlinearity, static wind load, and unbalanced construction load on the structural stability during construction. Besides, the structural nonlinear stability in different construction schemes and the determination of temporary pier position are also studied. The nonlinear stability safety factors are calculated to demonstrate the rationality and safety of construction schemes. The results show that the nonlinear stability safety factors of this bridge during construction meet the design requirement and the minimum value occurs in the maximum double cantilever stage. Besides, the nonlinear stability of the structure in the side of edge-pylon meets the design requirement in the two construction schemes. Furthermore, the temporary pier can improve the structure stability, effectively, and the actual position is reasonable. In addition, the local buckling of steel girder occurs earlier than overall instability under load in some cable tension stages. Finally, static wind load and the unbalanced construction load should be considered in the stability analysis for the adverse impact.

  5. Continuous prestressed concrete girder bridges volume 1 : literature review and preliminary designs.

    Science.gov (United States)

    2012-06-01

    The Texas Department of Transportation (TxDOT) is currently designing typical highway bridge structures as simply supported using standard precast, pretensioned girders. TxDOT is interested in developing additional economical design alternatives for ...

  6. Continuous prestressed concrete girder bridges, volume 2 : analysis, testing, and recommendations.

    Science.gov (United States)

    2016-12-01

    The Texas Department of Transportation designs typical highway bridge structures as simple span systems using : standard precast, pretensioned girders. Spans are limited to about 150 ft due to weight and length restrictions on : transporting the prec...

  7. Design of bridge crane girder strain acquisition system based on virtual instrument

    Directory of Open Access Journals (Sweden)

    Wenxue LIU

    Full Text Available Girder is an important part of the bridge crane, which is also the main force element. In order to prevent accidents, it is necessary to collect the bridge crane girder stress data to analyse the fatigue life. This paper constructs a bridge crane girder strain acquisition system. The hardware system consists of sensors, connectors, data acquisition cards, wireless data transmission groups, POE power and host computer. The software system consists of NI MAX to interface with the computer's NI hardware and software resources,and LabVIEW programming to display and storage the girder strain data. Through this system, positions and working days strain data acquisition for the 50/10 t bridge crane girder gets the key positions strain data. The results show that the girder strain data acquisition system runs stably, channel signals of acquisition task transmit accurately, and the terminal data stores competely, meeting the detection requirements, which provides an important data support for the subsequent fatigue analysis and accurate remaining service life prediction of the crane girder.

  8. Comparison Between PCI and Box Girder in BridgesPrestressed Concrete Design

    Science.gov (United States)

    Rahmawati, Cut; Zainuddin, Z.; Is, Syafridal; Rahim, Robbi

    2018-04-01

    This research is done by comparing PCI and Box Girder types of prestressed concrete design. The method used is load balance. Previous studies have just discussed the differences in terms of effectiveness and economics. In this study, the researchers want to know the design process by comparing the working forces, the resulting moment, and the losses of the prestressed. As the case in this study, the researchers used the bridge with the span of 31 meters. The tendon pulling system was conducted with post-tensioning system The analysis result showed that prestressed of the Girder box type sustained the greatest moment due to the combination of its own weight, additional dead load, lane load, and wind load of 44,029 kNm, while the biggest moment of PCI Girder was 7,556.75 KNm The Girder beam box experiences greater moment and shear force than PCI Girder. This is the effect of the weight of its own Girderboxwaslarger than PCI Girder. The losses ofprestressed style of Girderboxand PCI Girder type were 24.85% and 26.32%, respectively.Moreover, it showed that the type of Girder box is cheaper, easier, and more efficient than PCI Girder.

  9. Creep analysis and torsional vibration analysis of cable-stayed bridges with two edge composite girders; Nishuketa gosei kozo shachokyo no creep kaiseki to nejiri shindo kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Hoshino, M. [Nihon University, Tokyo (Japan). College of Science and Technology

    1996-07-21

    This paper describes the creep analysis and torsional vibration analysis of cable-stayed bridges with two edge composite girders. The girder is composed of the concrete slab and the steel girder. I-girders are placed at both edges of the profile. Such a type of bridge was investigated. As the stress migrates by the creep of concrete slab, it is necessary to evaluate the influence of this creep precisely in designing. In the analysis, the composite girder was expressed not by the single member, but by the binary member consisting of concrete member and steel member. Two methods were employed, i.e., method A in which both members are connected by the rigid body beam and method B in which the profile of concrete is converted into the profile of steel. The method A provided better accuracy, but the method B was often sufficient. Torsional rigidity of the open profile structure was much smaller than that of the box profile. As the torsional natural frequency was low, proper torsional vibration analysis was indispensable especially from the viewpoint of wind resistance. Two methods were employed, which utilize the vibration analysis method for general space frame structures. Results of both methods were agreed mutually, but the second method provided better calculation efficiency. 10 refs., 9 figs., 6 tabs.

  10. Simplified method for the transverse bending analysis of twin celled concrete box girder bridges

    Science.gov (United States)

    Chithra, J.; Nagarajan, Praveen; S, Sajith A.

    2018-03-01

    Box girder bridges are one of the best options for bridges with span more than 25 m. For the study of these bridges, three-dimensional finite element analysis is the best suited method. However, performing three-dimensional analysis for routine design is difficult as well as time consuming. Also, software used for the three-dimensional analysis are very expensive. Hence designers resort to simplified analysis for predicting longitudinal and transverse bending moments. Among the many analytical methods used to find the transverse bending moments, SFA is the simplest and widely used in design offices. Results from simplified frame analysis can be used for the preliminary analysis of the concrete box girder bridges.From the review of literatures, it is found that majority of the work done using SFA is restricted to the analysis of single cell box girder bridges. Not much work has been done on the analysis multi-cell concrete box girder bridges. In this present study, a double cell concrete box girder bridge is chosen. The bridge is modelled using three- dimensional finite element software and the results are then compared with the simplified frame analysis. The study mainly focuses on establishing correction factors for transverse bending moment values obtained from SFA.

  11. Effect of longitudinal stiffening on bridge girder webs at incremental launching stage

    Directory of Open Access Journals (Sweden)

    Carlos Graciano

    2015-01-01

    Full Text Available Patch loading is a predominant load case at incremental bridge launching. Bridge girder webs are frequently provided with longitudinal stiffeners to increase in-service shear and bending strength, and its effect has been included in design codes. However, no straightforward rules are given to account for the influence of such stiffeners on improving the patch loading resistance. This paper presents a review of some available formulae found in the literature to estimate the girder ultimate strength including the provisions of the European, American and Colombian design codes. Additionally, a nonlinear finite element analysis is conducted on three case studies related to actual launched bridges. The case studies are also used to study the influence of the longitudinal stiffener and girder depth on the girder capacity. Different load-displacement responses are observed depending on the girder depth. Finally, the finite element analysis shows to what extent the longitudinal stiffeners can increase the patch loading capacity of bridge girder webs during launching.

  12. Dynamic Magnification Factor in a Box-Shape Steel Girder

    Science.gov (United States)

    Rahbar-Ranji, A.

    2014-01-01

    The dynamic effect of moving loads on structures is treated as a dynamic magnification factor when resonant is not imminent. Studies have shown that the calculated magnification factors from field measurements could be higher than the values specified in design codes. It is the main aim of present paper to investigate the applicability and accuracy of a rule-based expression for calculation of dynamic magnification factor for lifting appliances used in marine industry. A steel box shape girder of a crane is considered and transient dynamic analysis using computer code ANSYS is implemented. Dynamic magnification factor is calculated for different loading conditions and compared with rule-based equation. The effects of lifting speeds, acceleration, damping ratio and position of cargo are examined. It is found that rule-based expression underestimate dynamic magnification factor.

  13. End region detailing of pretensioned concrete bridge girders.

    Science.gov (United States)

    2013-03-01

    End region detailing has significant effect on the serviceability, behavior, and capacity of pretensioned concrete girders. : In this project, experimental and analytical research programs were conducted to evaluate and quantify the effects of : diff...

  14. Distortional Buckling Analysis of Steel-Concrete Composite Girders in Negative Moment Area

    Directory of Open Access Journals (Sweden)

    Zhou Wangbao

    2014-01-01

    Full Text Available Distortional buckling is one of the most important buckling modes of the steel-concrete composite girder under negative moment. In this study, the equivalent lateral and torsional restraints of the bottom flange of a steel-concrete composite girder under negative moments due to variable axial forces are thoroughly investigated. The results show that there is a coupling effect between the applied forces and the lateral and torsional restraint of the bottom flange. Based on the calculation formula of lateral and torsional restraints, the critical buckling stress of I-steel-concrete composite girders and steel-concrete composite box girders under variable axial force is obtained. The critical bending moment of the steel-concrete composite girders can be further calculated. Compared to the traditional calculation methods of elastic foundation beam, the paper introduces an improved method, which considers coupling effect of the external loads and the foundation spring constraints of the bottom flange. Fifteen examples of the steel-concrete composite girders in different conditions are calculated. The calculation results show a good match between the hand calculation and the ANSYS finite element method, which validated that the analytic calculation method proposed in this paper is practical.

  15. Numerical Analysis on Variation of Dynamic Response of Girder Bridges with Torsional Reinforcement Panels

    Directory of Open Access Journals (Sweden)

    Kang Jae-Yoon

    2015-01-01

    Full Text Available The dynamic flexural behaviour of the railway bridge is influenced by its torsional behaviour. Especially, in the case of girder railway bridges, the dynamic response tends to amplify when the natural frequency in flexure (1st vibration mode is close to that in torsion (2nd vibration mode. In order to prevent such situation, it is necessary to adopt a flexural-to-torsional natural frequency ratio larger than 120%. This study proposes a solution shifting the natural frequency in torsion to high frequency range and restraining torsion by installing concrete panels on the bottom flange of the girder so as to prevent the superposition of the responses in the girder bridge. The applicability of this solution is examined by finite element analysis of the shift of the torsional natural frequency and change in the dynamic response according to the installation of the concrete panels. The analytical results for a 30 m-span girder railway bridge indicate that installing the concrete panels increases the natural frequency in torsion by restraining the torsional behaviour and reduces also the overall dynamic response. It is seen that the installation of 100 mm-thick concrete panels along a section of 4 m at both extremities of the girder can reduce the dynamic response by more than 30%.

  16. Strength and durability of near-surface mounted CFRP bars for shear strengthening reinforced concrete bridge girders : final report appendices.

    Science.gov (United States)

    2012-03-01

    During the interstate expansion of the 1950s, many conventionally reinforced concrete deck girder bridges were built throughout the country. These aging bridges commonly exhibit diagonal cracking and rate inadequately for shear, thus they are candida...

  17. Strength and durability of near-surface mounted CFRP bars for shear strengthening reinforced concrete bridge girders : appendices.

    Science.gov (United States)

    2012-01-01

    During the interstate expansion of the 1950s, many conventionally reinforced concrete deck girder bridges were built throughout the country. These aging bridges commonly exhibit diagonal cracking and rate inadequately for shear, thus they are candida...

  18. Strength and durability of near-surface mounted CFRP bars for shear strengthening reinforced concrete bridge girders.

    Science.gov (United States)

    2012-03-01

    During the interstate expansion of the 1950s, many conventionally reinforced concrete deck girder bridges were built throughout the country. These aging bridges commonly exhibit diagonal cracking and rate inadequately for shear, thus they are candida...

  19. Strength and durability of near-surface mounted CFRP bars for shear strengthening reinforced concrete bridge girders : final report.

    Science.gov (United States)

    2012-03-01

    During the interstate expansion of the 1950s, many conventionally reinforced concrete deck girder bridges were built throughout the country. These aging bridges commonly exhibit diagonal cracking and rate inadequately for shear, thus they are candida...

  20. STRENGTHENING CONCRETE HOLLOW SECTION GIRDER BRIDGE USING POLYURETHANE-CEMENT MATERIAL (PART B

    Directory of Open Access Journals (Sweden)

    Haleem K. Hussain

    2018-01-01

    Full Text Available This paper presents experimental study to retrofitted reinforced concrete Hollow Section Bridge. The study was carried out on the White River Bridge structure (Bai xi da Qiao / China. The effect of retrofitting on stress and strain of beams at the critical section was studied. Evaluating the bridges girder after strengthening using new material called PolyurethaneCement material (PUC as an external material .This study present the strain and deflection before and after strengthening the bridge girders. The results has shown that the overall state of the bridge structural strengthening is in good condition. The enhancement was significant in stiffness of the bridge structure. Regarding to the results of static load test, the experimental values strain and deflection are less than theoretical values, indicating that the stiffness of the structure, overall deformation and integrity satisfy the designed and standard requirements and the working performance are in good condition, and flexure capacity has a certain surplus.

  1. A new solution of measuring thermal response of prestressed concrete bridge girders for structural health monitoring

    International Nuclear Information System (INIS)

    Jiao, Pengcheng; Borchani, Wassim; Hasni, Hassene; Lajnef, Nizar

    2017-01-01

    This study develops a novel buckling-based mechanism to measure the thermal response of prestressed concrete bridge girders under continuous temperature changes for structural health monitoring. The measuring device consists of a bilaterally constrained beam and a piezoelectric polyvinylidene fluoride transducer that is attached to the beam. Under thermally induced displacement, the slender beam is buckled. The post-buckling events are deployed to convert the low-rate and low-frequency excitations into localized high-rate motions and, therefore, the attached piezoelectric transducer is triggered to generate electrical signals. Attaching the measuring device to concrete bridge girders, the electrical signals are used to detect the thermal response of concrete bridges. Finite element simulations are conducted to obtain the displacement of prestressed concrete girders under thermal loads. Using the thermal-induced displacement as input, experiments are carried out on a 3D printed measuring device to investigate the buckling response and corresponding electrical signals. A theoretical model is developed based on the nonlinear Euler–Bernoulli beam theory and large deformation assumptions to predict the buckling mode transitions of the beam. Based on the presented theoretical model, the geometry properties of the measuring device can be designed such that its buckling response is effectively controlled. Consequently, the thermally induced displacement can be designed as limit states to detect excessive thermal loads on concrete bridge girders. The proposed solution sufficiently measures the thermal response of concrete bridges. (paper)

  2. A new solution of measuring thermal response of prestressed concrete bridge girders for structural health monitoring

    Science.gov (United States)

    Jiao, Pengcheng; Borchani, Wassim; Hasni, Hassene; Lajnef, Nizar

    2017-08-01

    This study develops a novel buckling-based mechanism to measure the thermal response of prestressed concrete bridge girders under continuous temperature changes for structural health monitoring. The measuring device consists of a bilaterally constrained beam and a piezoelectric polyvinylidene fluoride transducer that is attached to the beam. Under thermally induced displacement, the slender beam is buckled. The post-buckling events are deployed to convert the low-rate and low-frequency excitations into localized high-rate motions and, therefore, the attached piezoelectric transducer is triggered to generate electrical signals. Attaching the measuring device to concrete bridge girders, the electrical signals are used to detect the thermal response of concrete bridges. Finite element simulations are conducted to obtain the displacement of prestressed concrete girders under thermal loads. Using the thermal-induced displacement as input, experiments are carried out on a 3D printed measuring device to investigate the buckling response and corresponding electrical signals. A theoretical model is developed based on the nonlinear Euler-Bernoulli beam theory and large deformation assumptions to predict the buckling mode transitions of the beam. Based on the presented theoretical model, the geometry properties of the measuring device can be designed such that its buckling response is effectively controlled. Consequently, the thermally induced displacement can be designed as limit states to detect excessive thermal loads on concrete bridge girders. The proposed solution sufficiently measures the thermal response of concrete bridges.

  3. Complex Method Mixed with PSO Applying to Optimization Design of Bridge Crane Girder

    Directory of Open Access Journals (Sweden)

    He Yan

    2017-01-01

    Full Text Available In engineer design, basic complex method has not enough global search ability for the nonlinear optimization problem, so it mixed with particle swarm optimization (PSO has been presented in the paper,that is the optimal particle evaluated from fitness function of particle swarm displacement complex vertex in order to realize optimal principle of the largest complex central distance.This method is applied to optimization design problems of box girder of bridge crane with constraint conditions.At first a mathematical model of the girder optimization has been set up,in which box girder cross section area of bridge crane is taken as the objective function, and its four sizes parameters as design variables, girder mechanics performance, manufacturing process, border sizes and so on requirements as constraint conditions. Then complex method mixed with PSO is used to solve optimization design problem of cane box girder from constrained optimization studying approach, and its optimal results have achieved the goal of lightweight design and reducing the crane manufacturing cost . The method is reliable, practical and efficient by the practical engineer calculation and comparative analysis with basic complex method.

  4. Sensitivity and statistical analysis within the elaboration of steel plated girder resistance

    Czech Academy of Sciences Publication Activity Database

    Melcher, J.; Škaloud, Miroslav; Kala, Z.; Karmazínová, M.

    2009-01-01

    Roč. 5, č. 2 (2009), s. 120-126 ISSN 1816-112X. [International conf. on steel and aluminium structures /6./. Oxford, 24.06.2007-27.06.2007] Institutional research plan: CEZ:AV0Z20710524 Keywords : steel structures * fatigue * sensitivity * imperfection * plated girder Subject RIV: JM - Building Engineering

  5. Dynamic Responses of Continuous Girder Bridges with Uniform Cross-Section under Moving Vehicular Loads

    OpenAIRE

    Gao, Qingfei; Wang, Zonglin; Jia, Hongyu; Liu, Chenguang; Li, Jun; Guo, Binqiang; Zhong, Junfei

    2015-01-01

    To address the drawback of traditional method of investigating dynamic responses of the continuous girder bridge with uniform cross-section under moving vehicular loads, the orthogonal experimental design method is proposed in this paper. Firstly, some empirical formulas of natural frequencies are obtained by theoretical derivation and numerical simulation. The effects of different parameters on dynamic responses of the vehicle-bridge coupled vibration system are discussed using our own progr...

  6. Reliability Assessment for PSC Box-Girder Bridges Based on SHM Strain Measurements

    Directory of Open Access Journals (Sweden)

    Chuang Chen

    2017-01-01

    Full Text Available A reliability assessment method for prestressed concrete (PSC continuous box-girder bridges based on structural health monitoring (SHM strain measurements was proposed. First, due to the fact that measured strain was compositive and the variation periods of its components were different, a series of limit state equations under normal use limit state were given. Then, a linear fitting method was used to determine the relationship between the ambient temperature and the measured strain, which was aimed at extracting the vehicle load effect and the temperature load effect from the measured strain. Finally, according to the equivalent normalization method, the load effects unsatisfying the normal distribution by probability density function fitting were transformed, and the daily failure probabilities of monitored positions were calculated for evaluating the safety state of the girder. The results show that (1 the top plate of the box girder is more sensitive than the bottom plate to the high temperature, (2 the daily and seasonal strain variations induced by uniform temperature reveal an inconsistent tendency to the seasonal variation for mid-span cross sections, and (3 the generalized extreme value distribution is recommended for temperature gradient stress and vehicle induced stress fitting for box-girder bridges.

  7. Design proposal for ultimate shear strength of tapered steel plate girders

    Directory of Open Access Journals (Sweden)

    A. Bedynek

    2017-03-01

    Full Text Available Numerous experimental and numerical studies on prismatic plate girders subjected to shear can be found in the literature. However, the real structures are frequently designed as non-uniform structural elements. The main objective of the research is the development of a new proposal for the calculation of the ultimate shear resistance of tapered steel plate girders taking into account the specific behaviour of such members. A new mechanical model is presented in the paper and it is used to show the differences between the behaviour of uniform and tapered web panels subjected to shear. EN 1993-1-5 design specifications for the determination of the shear strength for rectangular plates are improved in order to assess the shear strength of tapered elements. Numerical studies carried out on tapered steel plate girders subjected to shear lead to confirm the suitability of the mechanical model and the proposed design expression.

  8. Numerical analysis of dynamic response of vehicle–bridge coupled system on long-span continuous girder bridge

    Directory of Open Access Journals (Sweden)

    Lipeng An

    2016-07-01

    Full Text Available To systematically study the vehicle–bridge coupled dynamic response and its change rule with different parameters, a vehicle model with seven degrees of freedom was built and the total potential energy of vehicle space vibration system was deduced. Considering the stimulation of road roughness, the dynamic response equation of vehicle–bridge coupled system was established in accordance with the elastic system principle of total potential energy with stationary value and the “set-in-right-position” rule. On the basis of the self-compiled Fortran program and bridge engineering, the dynamic response of long-span continuous girder bridge under vehicle load was studied. This study also included the calculation of vehicle impact coefficient, evaluation of vibration comfort, and analysis of dynamic response parameters. Results show the impact coefficient changes with lane number and is larger than the value calculated by the “general code for design of highway bridges and culverts (China”. The Dieckmann index of bridge vibration is also related to lane number, and the vibration comfort evaluation is good in normal conditions. The relevant conclusions from parametric analyses have practical significance to dynamic design and daily operation of long-span continuous girder bridges in expressways. Safety and comfort are expected to improve significantly with further control of the vibration of vehicle–bridge system.

  9. Estimation of Curvature Changes for Steel-Concrete Composite Bridge Using Fiber Bragg Grating Sensors

    OpenAIRE

    Kang, Donghoon; Chung, Wonseok

    2013-01-01

    This study is focused on the verification of the key idea of a newly developed steel-concrete composite bridge. The key idea of the proposed bridge is to reduce the design moment by applying vertical prestressing force to steel girders, so that a moment distribution of a continuous span bridge is formed in a simple span bridge. For the verification of the key technology, curvature changes of the bridge should be monitored sequentially at every construction stage. A pair of multiplexed FBG sen...

  10. Structural health monitoring of an existing PC box girder bridge with distributed HCFRP sensors in a destructive test

    Science.gov (United States)

    Yang, Caiqian; Wu, Zhishen; Zhang, Yufeng

    2008-06-01

    The application of hybrid carbon fiber reinforced polymer (HCFRP) sensors was addressed to monitor the structural health of an existing prestressed concrete (PC) box girder bridge in a destructive test. The novel HCFRP sensors were fabricated with three types of carbon tows in order to realize distributed and broad-based sensing, which is characterized by long-gauge length and low cost. The HCFRP sensors were bonded on the bottom and side surfaces of the existing bridge to monitor its structural health. The gauge lengths of the sensors bonded on the bottom and side surfaces were 1.5 m and 1.0 m, respectively. The HCFRP sensors were distributed on the bridge for two purposes. One was to detect damage and monitor the structural health of the bridge, such as the initiation and propagation of new cracks, strain distribution and yielding of steel reinforcements. The other purpose was to monitor the propagation of existing cracks. The good relationship between the change in electrical resistance and load indicates that the HCFRP sensors can provide actual infrastructures with a distributed damage detection and structural health monitoring system. Corrections were made to this article on 13 May 2008. The corrected electronic version is identical to the print version.

  11. Structural health monitoring of an existing PC box girder bridge with distributed HCFRP sensors in a destructive test

    International Nuclear Information System (INIS)

    Yang Caiqian; Wu Zhishen; Zhang Yufeng

    2008-01-01

    The application of hybrid carbon fiber reinforced polymer (HCFRP) sensors was addressed to monitor the structural health of an existing prestressed concrete (PC) box girder bridge in a destructive test. The novel HCFRP sensors were fabricated with three types of carbon tows in order to realize distributed and broad-based sensing, which is characterized by long-gauge length and low cost. The HCFRP sensors were bonded on the bottom and side surfaces of the existing bridge to monitor its structural health. The gauge lengths of the sensors bonded on the bottom and side surfaces were 1.5 m and 1.0 m, respectively. The HCFRP sensors were distributed on the bridge for two purposes. One was to detect damage and monitor the structural health of the bridge, such as the initiation and propagation of new cracks, strain distribution and yielding of steel reinforcements. The other purpose was to monitor the propagation of existing cracks. The good relationship between the change in electrical resistance and load indicates that the HCFRP sensors can provide actual infrastructures with a distributed damage detection and structural health monitoring system. Corrections were made to this article on 13 May 2008. The corrected electronic version is identical to the print version

  12. Acoustic emission techniques applied to conventionally reinforced concrete bridge girders.

    Science.gov (United States)

    2008-09-01

    Reinforced concrete (RC) bridges generally operate at service-level loads except during discrete overload events that can reduce the integrity of the structure by initiating concrete cracks, widening or extending of existing concrete cracks, as well ...

  13. Erection of the stiffening girder of the Akashi Kaikyo bridge; Akashi Kaikyo Ohashi hokoketa (sono 2) koji no genchi seko

    Energy Technology Data Exchange (ETDEWEB)

    Otsuki, M.; Inoue, M.; Ueno, Y.; Matsumura, T.; Oe, S. [Kawasaki Heavy Industries, Ltd., Kobe (Japan)

    1998-12-20

    The Akashi Kaikyo Bridge is 3,911m long with a center span of 1,991m, making it the longest suspension bridge in the world. Much careful attention has been given to the erection planning details in order to construct the bridge to withstand the harsh environmental conditions of that area. This report details the characteristics of the bridge stiffening girder and erection procedure, and the effects of the Hyogoken-Nanbu Earthquake. (author)

  14. Existing Steel Railway Bridges Evaluation

    Science.gov (United States)

    Vičan, Josef; Gocál, Jozef; Odrobiňák, Jaroslav; Koteš, Peter

    2016-12-01

    The article describes general principles and basis of evaluation of existing railway bridges based on the concept of load-carrying capacity determination. Compared to the design of a new bridge, the modified reliability level for existing bridges evaluation should be considered due to implementation of the additional data related to bridge condition and behaviour obtained from regular inspections. Based on those data respecting the bridge remaining lifetime, a modification of partial safety factors for actions and materials could be respected in the bridge evaluation process. A great attention is also paid to the specific problems of determination of load-caring capacity of steel railway bridges in service. Recommendation for global analysis and methodology for existing steel bridge superstructure load-carrying capacity determination are described too.

  15. Existing Steel Railway Bridges Evaluation

    Directory of Open Access Journals (Sweden)

    Vičan Josef

    2016-12-01

    Full Text Available The article describes general principles and basis of evaluation of existing railway bridges based on the concept of load-carrying capacity determination. Compared to the design of a new bridge, the modified reliability level for existing bridges evaluation should be considered due to implementation of the additional data related to bridge condition and behaviour obtained from regular inspections. Based on those data respecting the bridge remaining lifetime, a modification of partial safety factors for actions and materials could be respected in the bridge evaluation process. A great attention is also paid to the specific problems of determination of load-caring capacity of steel railway bridges in service. Recommendation for global analysis and methodology for existing steel bridge superstructure load-carrying capacity determination are described too.

  16. Evaluation of the Structure Stability of a Plate Girder Bridge Using MIDAS Structure Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eui Soo; Kim, Jong Hyuk [National Forensic Service, Wonju (Korea, Republic of)

    2014-04-15

    Recently, as a means of resolving the issue of legal liability in the event of an accident or a disaster, a wide variety of simulation techniques, such as structural and structure-fluid interaction analysis, have been used in the field of forensic engineering. The plate girder bridge discussed in this paper was being constructed between a pier and an abutment to expand an existing bridge, but an accident whereby the bridge overturned occurred at the end of the concrete laying process for a protective wall. This accident was caused by additional loads not being considered at the time of the design as well as the actual construction being different from the design. The additional loads ultimately generated a negative support force. In this study, we determined the cause of the accident by comparing the structural stability of the original design with that of the additional, non-conforming construction using MIDAS structural analysis.

  17. Evaluation of the Structure Stability of a Plate Girder Bridge Using MIDAS Structure Analysis

    International Nuclear Information System (INIS)

    Kim, Eui Soo; Kim, Jong Hyuk

    2014-01-01

    Recently, as a means of resolving the issue of legal liability in the event of an accident or a disaster, a wide variety of simulation techniques, such as structural and structure-fluid interaction analysis, have been used in the field of forensic engineering. The plate girder bridge discussed in this paper was being constructed between a pier and an abutment to expand an existing bridge, but an accident whereby the bridge overturned occurred at the end of the concrete laying process for a protective wall. This accident was caused by additional loads not being considered at the time of the design as well as the actual construction being different from the design. The additional loads ultimately generated a negative support force. In this study, we determined the cause of the accident by comparing the structural stability of the original design with that of the additional, non-conforming construction using MIDAS structural analysis

  18. Damage identification method for continuous girder bridges based on spatially-distributed long-gauge strain sensing under moving loads

    Science.gov (United States)

    Wu, Bitao; Wu, Gang; Yang, Caiqian; He, Yi

    2018-05-01

    A novel damage identification method for concrete continuous girder bridges based on spatially-distributed long-gauge strain sensing is presented in this paper. First, the variation regularity of the long-gauge strain influence line of continuous girder bridges which changes with the location of vehicles on the bridge is studied. According to this variation regularity, a calculation method for the distribution regularity of the area of long-gauge strain history is investigated. Second, a numerical simulation of damage identification based on the distribution regularity of the area of long-gauge strain history is conducted, and the results indicate that this method is effective for identifying damage and is not affected by the speed, axle number and weight of vehicles. Finally, a real bridge test on a highway is conducted, and the experimental results also show that this method is very effective for identifying damage in continuous girder bridges, and the local element stiffness distribution regularity can be revealed at the same time. This identified information is useful for maintaining of continuous girder bridges on highways.

  19. Experimental Analysis of Stiffness of the Riveted Steel Railway Bridge Deck Members’ Joints

    Directory of Open Access Journals (Sweden)

    Gocál Jozef

    2014-12-01

    Full Text Available The paper deals with the real behaviour of the riveted steel railway bridge deck members’ connections with respect to their bending stiffness. Attention is paid to the stringer-to-cross beam connection as well as the cross beam-to-main girder connection. The stiffness of the two connections is investigated on the basis of evaluation of the experimentally determined stress response of the observed structural members to the actual traffic load on an existing railway bridge.

  20. Finite element model updating of a prestressed concrete box girder bridge using subproblem approximation

    Science.gov (United States)

    Chen, G. W.; Omenzetter, P.

    2016-04-01

    This paper presents the implementation of an updating procedure for the finite element model (FEM) of a prestressed concrete continuous box-girder highway off-ramp bridge. Ambient vibration testing was conducted to excite the bridge, assisted by linear chirp sweepings induced by two small electrodynamic shakes deployed to enhance the excitation levels, since the bridge was closed to traffic. The data-driven stochastic subspace identification method was executed to recover the modal properties from measurement data. An initial FEM was developed and correlation between the experimental modal results and their analytical counterparts was studied. Modelling of the pier and abutment bearings was carefully adjusted to reflect the real operational conditions of the bridge. The subproblem approximation method was subsequently utilized to automatically update the FEM. For this purpose, the influences of bearing stiffness, and mass density and Young's modulus of materials were examined as uncertain parameters using sensitivity analysis. The updating objective function was defined based on a summation of squared values of relative errors of natural frequencies between the FEM and experimentation. All the identified modes were used as the target responses with the purpose of putting more constrains for the optimization process and decreasing the number of potentially feasible combinations for parameter changes. The updated FEM of the bridge was able to produce sufficient improvements in natural frequencies in most modes of interest, and can serve for a more precise dynamic response prediction or future investigation of the bridge health.

  1. Composite Action in Prestressed NU I-Girder Bridge Deck Systems Constructed with Bond Breakers to Facilitate Deck Removal : Technical Summary

    Science.gov (United States)

    2017-11-01

    Results are reported from tests of small-scale push-off and large-scale composite NU I-girder specimens conducted to establish an interface connection detail that (1) Facilitates in-situ removal of the bridge deck without damaging prestressed girders...

  2. Steel-soil composite bridge

    DEFF Research Database (Denmark)

    Du, Guangli; Pettersson, Lars; Karoumi, Raid

    2017-01-01

    viability, while their environmental performance is overlooked. Today’s designers are urged to seek new design options to reduce the environmental burdens. Sweden owns more than 24574 bridges and most of them are short spans. Among them, the slab frame bridge (CFB) is a common solution. Soil steel composite...... bridge (SSCB), alternatively, is a functionally equivalent solution to CFB and shows advantages in low cost and easy construction. This paper compares the environmental performance between these two bridge types based on life cycle assessment (LCA). The analysis and result shows that, the SSCB...

  3. Double Girder Bridge Crane with Double Cycling: Scheduling Strategy and Performance Evaluation

    Directory of Open Access Journals (Sweden)

    Dandan Wang

    2014-01-01

    Full Text Available This paper introduces a novel quay crane design, double girder bridge crane (DGBC. DGBC is capable of handling containers of two adjacent bays simultaneously, avoiding crane collisions, saving travelling and reposition cost, and eventually improving terminal efficiency. This problem is formulated as a resource-constrained project scheduling with objective to minimize the maximum completion time. A two-stage heuristic algorithm is proposed in which an operating sequences on each bay is obtained by double cycling, and the integrated timetable for both bays is constructed by solving resource conflicts using the proposed minimum cost strategy. We examine effectiveness and performance of applying DGBC with double cycling. A case study is presented to illustrate how DGBC works with the two-stage method. Three extreme cases with respective conflict types are investigated to develop the performance bounds of DGBC with double cycling. The results show that DGBC can significantly improve terminal productivity, and outperforms single girder crane in both makespan and the lift operation percentage. The highest DGBC efficiency does not require maximum double cycles in two bay schedules; rather the integrated timetable for two bays is the main contribution to the DGBC performance as it yields better cooperation between two spreaders and the driver.

  4. Seismic vulnerability assessment of a continuous steel box girder ...

    Indian Academy of Sciences (India)

    Tae-Hyung Lee

    2018-02-07

    Feb 7, 2018 ... nonlinear time history analysis is the most widely used and the most reliable method ... the damage probability for the non-isolated bridge is larger than those of the isolated .... [17] and are adjusted for a simulated facilitation purpose. ..... function is assumed as a log-normal cumulative distribution function ...

  5. Seismic Retrofit of a Multispan Prestressed Concrete Girder Bridge with Friction Pendulum Devices

    Directory of Open Access Journals (Sweden)

    Alberto Maria Avossa

    2018-01-01

    Full Text Available The paper deals with the proposal and application of a procedure for the seismic retrofit of an existing multispan prestressed concrete girder bridge defined explicitly for the use of friction pendulum devices as an isolation system placed between piers top and deck. First, the outcomes of the seismic risk assessment of the existing bridge, performed using an incremental noniterative Nonlinear Static Procedure, based on the Capacity Spectrum Method as well as the Inelastic Demand Response Spectra, are described and discussed. Then, a specific multilevel design process, based on a proper application of the hierarchy of strength considerations and the Direct Displacement-Based Design approach, is adopted to dimension the FPD devices. Furthermore, to assess the impact of the FPD nonlinear behaviour on the bridge seismic response, a device model that reproduces the variation of the normal force and friction coefficient, the bidirectional coupling, and the large deformation effects during nonlinear dynamic analyses was used. Finally, the paper examines the effects of the FPD modelling parameters on the behaviour of the retrofitted bridge and assesses its seismic response with the results pointing out the efficiency of the adopted seismic retrofit solution.

  6. Estimation of Curvature Changes for Steel-Concrete Composite Bridge Using Fiber Bragg Grating Sensors

    Directory of Open Access Journals (Sweden)

    Donghoon Kang

    2013-01-01

    Full Text Available This study is focused on the verification of the key idea of a newly developed steel-concrete composite bridge. The key idea of the proposed bridge is to reduce the design moment by applying vertical prestressing force to steel girders, so that a moment distribution of a continuous span bridge is formed in a simple span bridge. For the verification of the key technology, curvature changes of the bridge should be monitored sequentially at every construction stage. A pair of multiplexed FBG sensor arrays is proposed in order to measure curvature changes in this study. They are embedded in a full-scale test bridge and measured local strains, which are finally converted to curvatures. From the result of curvature changes, it is successfully ensured that the key idea of the proposed bridge, expected theoretically, is viable.

  7. Dynamic Responses of Continuous Girder Bridges with Uniform Cross-Section under Moving Vehicular Loads

    Directory of Open Access Journals (Sweden)

    Qingfei Gao

    2015-01-01

    Full Text Available To address the drawback of traditional method of investigating dynamic responses of the continuous girder bridge with uniform cross-section under moving vehicular loads, the orthogonal experimental design method is proposed in this paper. Firstly, some empirical formulas of natural frequencies are obtained by theoretical derivation and numerical simulation. The effects of different parameters on dynamic responses of the vehicle-bridge coupled vibration system are discussed using our own program. Finally, the orthogonal experimental design method is proposed for the dynamic responses analysis. The results show that the effects of factors on dynamic responses are dependent on both the selected position and the type of the responses. In addition, the interaction effects between different factors cannot be ignored. To efficiently reduce experimental runs, the conventional orthogonal design is divided into two phases. It has been proved that the proposed method of the orthogonal experimental design greatly reduces calculation cost, and it is efficient and rational enough to study multifactor problems. Furthermore, it provides a good way to obtain more rational empirical formulas of the DLA and other dynamic responses, which may be adopted in the codes of design and evaluation.

  8. Estimation of Structure-Borne Noise Reduction Effect of Steel Railway Bridge Equipped with Floating Ladder Track and Floating Reinforced-Concrete Deck

    Science.gov (United States)

    Watanabe, Tsutomu; Sogabe, Masamichi; Asanuma, Kiyoshi; Wakui, Hajime

    A number of steel railway bridges have been constructed in Japan. Thin steel members used for the bridges easily tend to vibrate and generate structure-borne noise. Accordingly, the number of constructions of steel railway bridges tends to decrease in the urban areas from a viewpoint of environmental preservation. Then, as a countermeasure against structure-borne noise generated from steel railway bridges, we have developed a new type of the steel railway bridge equipped with a floating-ladder track and a floating reinforced-concrete (RC) deck. As a result of train-running experiment, it became apparent that the new steel railway bridge installed by double floating system has reduced a vibration velocity level by 10.5 dB(A) at main girder web as compared with a steel railway bridge installed by directly fastened track. This reduction effect was achieved by the ladder track and RC deck supported by resilient materials.

  9. Behaviour of parallel girders stabilised with U-frames

    DEFF Research Database (Denmark)

    Virdi, Kuldeep; Azzi, Walid

    2010-01-01

    Lateral torsional buckling is a key factor in the design of steel girders. Stability can be enhanced by cross-bracing, reducing the effective length and thus increasing the ultimate capacity. U-frames are an option often used to brace the girders when designing through type of bridges and where...... overhead bracing is not practical. This paper investigates the effect of the U-frame spacing on the stability of the parallel girders. Eigenvalue buckling analysis was undertaken with four different spacings of the U-frames. Results were extracted from finite element analysis, interpreted and conclusions...

  10. Analysis of a damaged and repaired pre-stressed concrete bridge girder by vehicle impact and effectiveness of repair procedure

    OpenAIRE

    Domínguez Mayans, Félix

    2014-01-01

    This thesis aims to study the structural consequences of the damages produced by vehicle impact in a pres-stressed concrete bridge girder and the repair procedure in a real case-study damaged after the bridge was opened to service. From the analysis of the situation of the beam and its damage state, a study of the repair actions carried out on this beam has been analyzed in order to determine the efficiency of the repair and if other alternatives are possible or more efficient. A stat...

  11. Influence of Pavement on Fatigue Performance of Urban Steel Box Girder Deck

    Directory of Open Access Journals (Sweden)

    Zheng Zhongyue

    2016-01-01

    Full Text Available Based on spatial finite element analysis method, the Influence of pavement on fatigue performance of orthotropic steel deck was analyzed in terms of pavement system, asphalt pavement stiffness. The result shows that compared with asphalt pavement system, RPC pavement system can not only obviously improve the stress condition of steel bridge deck, but also significantly extend the fatigue life of steel bridge panel; Increasing the stiffness of pavement layer can obviously reduce the stress amplitude of fatigue details, especially for direct contact with the pavement.

  12. Analysis on Adhesively-Bonded Joints of FRP-steel Composite Bridge under Combined Loading : Arcan Test Study and Numerical Modeling

    NARCIS (Netherlands)

    Jiang, X.; Qiang, X.; Kolstein, M.H.; Bijlaard, F.S.K.

    2016-01-01

    The research presented in this paper is an experimental study and numerical analysis on mechanical behavior of the adhesively-bonded joint between FRP sandwich bridge deck and steel girder. Generally, there are three typical stress states in the adhesively-bonded joint: shear stress, tensile stress,

  13. Comprehensive evaluation of fracture critical bridges.

    Science.gov (United States)

    2014-02-01

    Two-girder steel bridges are classified as fracture critical bridges based on the definition given in the AASHTO LRFD Bridge Design Specifications. In a fracture critical bridge a failure of a tension member leads to collapse of the bridge. However, ...

  14. Steel bridges structural health monitoring based on operational modal analysis accommodating evaluation of uncertainty

    Directory of Open Access Journals (Sweden)

    Saeid Jahan

    2017-11-01

    Full Text Available Structural damage detection is based on that the dynamic response of structure will change because of damage. Hence, it is possible to estimate the location and severity of damage leads to changes in the dynamic response before and after the damage. In this study, the genetic fuzzy system has been used for bridge structural health monitoring. A key objective of using genetic algorithms is to automate the design of fuzzy systems. This method is used for damage detection of a single span railway bridge with steel girders and a concrete bridge. For studying damage detection, the numerical models of these two bridges are built with the measured dynamic characteristics. A three-dimensional finite element model and a single two-dimensional girders model of the bridge have been constructed to study usefulness of the genetic fuzzy system for damage detection and the effectiveness of modeling. After analysis to control the uncertainties, the measured frequencies are contaminated with some noise and the effect of that on the achievement of damage detection method is evaluated. The present study has shown that the natural frequency has appropriate sensitivity to different damage scenarios in the structure. In addition, the natural frequency in comparison with other modal parameters, is less affected by random noise. Increasing the number of measurement modes and using torsional modes, will lead to an accurate damage diagnosis even in symmetrical structures.

  15. Analysis of Temperature and Longitudinal Stress of Very Large Flat Steel Box Girder in Cold Areas%寒冷地区特大扁平钢箱梁温度及纵向应力分析

    Institute of Scientific and Technical Information of China (English)

    胡铁明; 苟红兵; 张冠华; 丁科翔

    2015-01-01

    为指导寒冷地区钢箱梁桥的设计 ,以主跨436 m的钢箱梁斜拉桥——辽河特大桥为研究对象 ,对其扁平钢箱梁进行了为期8个月的温度监测 ,采用对比分析、极值分析、概率统计等方法分析钢箱梁跨中截面温度及纵向应力日变化趋势、总体变化规律及温度对纵向应力的影响情况.结果表明 :环境温度在20~45 ℃时 ,桥梁设计规范计算得到的钢箱梁顶板温度最大值小于实际监测值 ;钢箱梁连续24 h温度变化服从正弦曲线分布 ,纵向应力每天前6 h变化服从线性分布 ,后18 h服从高斯曲线分布 ;24h内温度极值点时的温度效应为其它活荷载总效应的5.7~6.5倍 ;顶板冬季最冷月平均纵向应力相比夏季最热月低12~35 M Pa ,底板冬季最冷月平均纵向应力相比夏季低12~16 M Pa.%To direct the design of steel box girder bridge in cold areas , the Liaohe River Bridge ,a steel box girder cable-stayed bridge with a main span of 436 m ,was taken as the study background ,the flat steel box girder of which experienced temperature monitoring lasting 8 months.A series of analytical methods ,including contrastive analysis ,ultimate value analysis and probabilistic computing were adopted to analyze the trend of daily variation of midspan cross-sec-tion temperature and longitudinal stress of steel box girder as well as the general variation law and the effect of temperature on longitudinal stress.The results of the analysis indicate that the maxi-mum value of the top plate temperature of steel box girder calculated in accordance with the bridge design specification is less than the actual measured value w hen the ambient temperature is around 20~45℃.The 24 h continuous temperature variation of the steel box girder conforms to the sinu-soidal distribution ,the first 6 h variation of longitudinal stress in each day complies with linear dis-tribution and the following 18 h longitudinal stress variation obeys Gaussian

  16. Steel plate reinforcement of orthotropic bridge decks

    NARCIS (Netherlands)

    Teixeira de Freitas, S.

    2012-01-01

    The PhD research is focused on the reinforcement of fatigue cracked orthotropic steel bridge decks (OBD) by adding a second steel plate to the existing deck. The main idea is to stiffen the existing deck plate, which will reduce the stresses at the fatigue sensitive details and extend the fatigue

  17. Long-Term Effects of Super Heavy-Weight Vehicles on Bridges

    OpenAIRE

    Wood, Scott M.; Akinci, Necip Onder; Liu, Judy; Bowman, Mark D

    2007-01-01

    A permit truck which exceeds the predefined limit of 108 kips is defined as a superload in Indiana. This study was conducted to examine the long-term effects of superload trucks on the performance of typical slab-on-girder bridges and to assess the likelihood of causing immediate damage. Typical steel and prestressed concrete slab-on-girder type bridges were analyzed using both beam line analysis and detailed finite element models. Furthermore, one prestressed concrete bridge and one steel br...

  18. Structural Health Monitoring and Time-Dependent Effects Analysis of Self-Anchored Suspension Bridge with Extra-Wide Concrete Girder

    Directory of Open Access Journals (Sweden)

    Guangpan Zhou

    2018-01-01

    Full Text Available The present work is aimed at studying the structural health status of Hunan Road Bridge, which is currently the widest concrete self-anchored suspension bridge in China. The monitoring data included the structural deformations, internal forces, and vibration characteristics from April 2015 to April 2016 were analyzed to evaluate the structural changes and safety. The influences brought by the ambient temperature changes and the dual effects composed of concrete shrinkage & creep (S&C and seasonal temperature changes were analyzed based on the measured data. The long-time effects of concrete S&C were predicted using the CEB-FIP 90 model and the age-adjusted effective modulus method based on the ANSYS beam finite element model. The measured data showed that the transverse displacements of towers were more significant than the longitudinal ones. The spatial effect of the extra-wide girder is significant, which performs as the longitudinal stresses change unevenly along the transverse direction. The seasonal ambient warming caused overall increases in girder compressive stresses, and the cooling resulted in decreases along with significant temperature gradient effects. The prediction results show that the cable anchoring positions at girder ends and tower tops will move towards the mid-span affected by concrete S&C. In terms of the middle region of mid-span girder, significant increases in longitudinal stresses of top plate and decreases in the ones of bottom plate will be caused by the significant deflection. Comprehensively, the increases in the girder compressive stresses of side-span bottom plate and mid-span top plate are worthy of attention when confronted with extreme high temperature during the bridge service life cycle.

  19. Longest cable-stayed bridge TATARA; Longest shachokyo Tatara Ohashi

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, K. [Hiroshima University, Hiroshima (Japan). Faculty of Engineering

    1998-06-15

    The world`s longest cable-stayed bridge Tatara having a central span of 890 m had the both ends closed in August 1997, linking Namakuchi Island and Omishima Island. Final finishing work is continuing for opening of the West Seto Expressway in the spring of 1999. A cable-stayed bridge supports the bridge girders by perpendicular components of tensile force of cables stayed obliquely. On the other hand, there is a concern that the girders may have axial compression force generated due to horizontal components of the force from the cable tensile force, which can cause buckling of the girders. Therefore, in order to suspend the girders efficiently by increasing the perpendicular components of the cable force, and moreover to suppress the axial compression force on the girders, it is more advantageous to make bridge towers high, hence the towers of this bridge are highest among the bridges on the Shimanami Ocean Road. This bridge whose long girders are stayed with 21-stage multi cables presented a problem in designing the buckling in steel girders near the towers due to the horizontal components of the force generated by the bridge. Discussions were given, therefore, by using load withstanding force experiments using a whole bridge model of 1/50 scale, buckling experiments on full-size reinforcing plate models, and load withstanding force analysis using a tower model. A number of other technical discussions were repeated, by which the world`s longest cable-stayed bridge was completed. 9 figs., 1 tab.

  20. Static and fatigue investigation of second generation steel free bridge decks

    International Nuclear Information System (INIS)

    Klowak, C.; Memon, Amjad H.; Mufti, Aftab A.

    2006-01-01

    This paper outlines the static and fatigue behavior of two different cast-in-place second generation steel-free bridge decks, which are: hybrid carbon fiber reinforced polymer (CFRP); and glass fiber reinforced polymer (GFRP) and steel strap design. Although cast monolithically, the first deck slab was divided into three segments with different reinforcement configurations. All three segments were tested under a 222kN cyclic loading to investigate fatigue behavior. The second bridge deck comprised an internal panel and two cantilevers and was equipped with a civionics system. The internal panel static test that this paper deals with is useful in the development of fatigue theory derived from fatigue testing of the first bridge deck. Test results form the cyclic loading of the first bridge deck indicated that the cross-sectional area of the reinforcement used in the test bridge deck can be reduced by 40% based on the reinforcement provided in the deck under service loads. The hybrid system also reduced the development of longitudinal crack widths to approximately 0.4 mm under service conditions, compared to the cracks that occurred approximately halfway between adjacent bridge girders that were determined to be roughly 1 mm in several first generation steel-free bridge decks constructed in Canada. Civionics, also discussed in the paper, is a new term coined from Civil-Electronics, which is the application of electronics to civil structures. The Civionics Specifications (2004) developed by ISIS Canada researchers are a helpful design tool for engineers and contractors to develop civionics and structural health monitoring systems for civil infrastructure that will last the lifetime of a structure. The use of civionics for the second test bridge deck ensured the survival of 100% of the 63 internal sensors throughout the rigors of the construction and casting of the deck. (author)

  1. CFRP-Strengthening and Long-Term Performance of Fatigue Critical Welds of a Steel Box Girder

    Directory of Open Access Journals (Sweden)

    Roland E. Koller

    2014-02-01

    Full Text Available Empa’s research efforts in the 1990s provided evidence that a considerable increase of the fatigue strength of welded aluminum beams can be achieved by externally bonding pultruded carbon fiber reinforced polymer (CFRP laminates using rubber-toughened epoxies over the fatigue-weak welding zone on their tensile flange. The reinforcing effect obtained is determined by the stiffness of the unidirectional CFRP laminate which has twice the elastic modulus of aluminum. One can therefore easily follow that an unstressed CFRP laminate reinforcement of welded beams made of steel will not lead to a substantial increase in fatigue strength of the steel structure. This consideration led to the idea of prestressing an external reinforcement of the welded zone. The present investigation describes experimental studies to identify the adhesive system suitable for achieving high creep and fatigue strength of the prestressed CFRP patch. Experimental results (Wöhler-fields of shear-lap-specimens and welded steel beams reinforced with prestressed CFRP laminates are presented. The paper concludes by presenting a field application, the reinforcement of a steel pendulum by adhesively bonded prestressed CFRP laminates to the tensile flanges of the welded box girder. Inspections carried out periodically on this structure revealed neither prestress losses nor crack initiation after nine years of service.

  2. INVESTIGATION OF LAUNCHING PROCESS FOR STEEL REINFORCED CONCRETE FRAMEWORK OF LARGE BRIDGES

    Directory of Open Access Journals (Sweden)

    V. A. Grechukhin

    2017-01-01

    Full Text Available Bridges are considered as the most complicated, labour-consuming and expensive components in roadway network of the Republic of Belarus. So their construction and operation are to be carried out at high technological level. One of the modern industrial methods is a cyclic longitudinal launching of large frameworks which provide the possibility to reject usage of expensive auxiliary facilities and reduce a construction period. There are several variants of longitudinal launching according to shipping conditions and span length: without launching girder, with launching girder, with top strut-framed beam in the form of cable-stayed system, with strut-framed beam located under span. While using method for the cyclic longitudinal launching manufacturing process of span is concentrated on the shore. The main task of the investigations is to select economic, quick and technologically simple type of the cyclic longitudinal launching with minimum resource- and labour inputs. Span launching has been comparatively analyzed with temporary supports being specially constructed within the span and according to capital supports with the help of launching girder. Conclusions made on the basis of calculations for constructive elements of span according to bearing ability of element sections during launching and also during the process of reinforced concrete plate grouting and at the stage of operation have shown that span assembly with application of temporary supports does not reduce steel spread in comparison with the variant excluding them. Results of the conducted investigations have been approbated in cooperation with state enterprise “Belgiprodor” while designing a bridge across river Sozh.

  3. Quality control and in-service inspection technology for hybrid-composite girder bridges.

    Science.gov (United States)

    2014-08-01

    This report describes efforts to develop quality control tools and in-service inspection technologies for the fabrication and construction of Hybrid Composite Beams (HCBs). HCBs are a new bridge technology currently being evaluated by the Missouri De...

  4. Acoustic emission techniques applied to conventionally reinforced concrete bridge girders : final report.

    Science.gov (United States)

    2008-09-01

    Reinforced concrete (RC) bridges generally operate at service-level loads except during discrete overload events that can reduce the integrity of the structure by initiating concrete cracks, widening or extending of existing concrete cracks, as well ...

  5. Bridge and steel structures. History and vision on bridge erection; Kyoryo kokozobutsu. Kasetsu gijutsu no shorai

    Energy Technology Data Exchange (ETDEWEB)

    Mukai, S.; Hayashi, T. [Sumitomo Heavy Industries, Ltd., Tokyo (Japan)

    1998-08-20

    This paper describes the progress of bridge erection technology. It introduces the results of cable erection, rotated/extruded erection, and cantilever erection. The cable erection is a multi point suspension erection using cables. For the rotated/extruded erection, the monolithic construction is conducted on a working yard set in a right angle to the construction position, and the horizontal beams of the bridge piers (corbel girders) are constructed by the rotated method using a slewing base incorporated around the bridge piers at one side. For the construction of stiffening girders of Innoshima-ohashi Bridge of Honshu-Shikoku Joint Bridge in 1978, trussed face bar blocks were extruded from the main tower in order using a travel crane. For the suspension bridges and cable stayed bridges, main towers were erected using various types of cranes. The erection of Tamashima-ohashi Bridge with a weight of 500 ton using an offshore floating crane is introduced as a large block method. Analysis methods and measurement techniques at the site are used in order to analyze the shape in each step under the erection and to ensure the accurate final complete shape. Reduction of the construction cost, improvement of erection technology, and technology development for large-scale projects are subjects in the future. 22 refs., 8 figs., 1 tab.

  6. Development of guidelines for transportation of prestressed concrete girders.

    Science.gov (United States)

    2011-11-01

    "Prestressed concrete girders are an economical superstructure system for bridges. With the : advent of higher strength concretes and more effi cient cross sections, the use of long span (>100 : ft.) prestressed girders are now specifi ed. Such long ...

  7. Repair of cracked prestressed concrete girders, I-565, Huntsville, Alabama.

    Science.gov (United States)

    2011-07-01

    Wide cracks were discovered in prestressed concrete bridge girders shortly after their construction in Huntsville, Alabama. Previous investigations of these continuous-for-live-load girders revealed that the cracking resulted from restrained thermal ...

  8. Live-Load Testing Application Using a Wireless Sensor System and Finite-Element Model Analysis of an Integral Abutment Concrete Girder Bridge

    Directory of Open Access Journals (Sweden)

    Robert W. Fausett

    2014-01-01

    Full Text Available As part of an investigation on the performance of integral abutment bridges, a single-span, integral abutment, prestressed concrete girder bridge near Perry, Utah was instrumented for live-load testing. The live-load test included driving trucks at 2.24 m/s (5 mph along predetermined load paths and measuring the corresponding strain and deflection. The measured data was used to validate a finite-element model (FEM of the bridge. The model showed that the integral abutments were behaving as 94% of a fixed-fixed support. Live-load distribution factors were obtained using this validated model and compared to those calculated in accordance to recommended procedures provided in the AASHTO LRFD Bridge Design Specifications (2010. The results indicated that if the bridge was considered simply supported, the AASHTO LRFD Specification distribution factors were conservative (in comparison to the FEM results. These conservative distribution factors, along with the initial simply supported design assumption resulted in a very conservative bridge design. In addition, a parametric study was conducted by modifying various bridge properties of the validated bridge model, one at a time, in order to investigate the influence that individual changes in span length, deck thickness, edge distance, skew, and fixity had on live-load distribution. The results showed that the bridge properties with the largest influence on bridge live-load distribution were fixity, skew, and changes in edge distance.

  9. Aerodynamic stability study of a long-span prestressed concrete cable-stayed bridge. Aerodynamic behavior of edge box girder under uniform flow; Chodai PC shachokyo no taifu anteisei ni kansuru kenkyu. Ichiyoryuchu ni okeru edge girder keishiki no kuriki tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, T. [Obayashi Corp., Tokyo (Japan)

    1999-01-10

    In recent years, the construction of long-span bridges is on the increase. Prestressed concrete cable-stayed bridges are dynamically very efficient structures of relatively low cost that blend in well with the landscape. Maintenance is also easy. Consequently, the adoption of edge box girders for cable-stayed bridges is increasing worldwide, but problems related to the aerodynamic stability of the structure have emerged. The aerodynamic stability of edge box girders for a prestressed concrete cable-stayed bridge was investigated under uniform flow conditions by conducting several wind tunnel experiments. As a result, the section of the bridge deck was optimized to prevent torsional flutter within an angle of attack varying from -5 to +5 degrees. It is therefore possible to guarantee the aerodynamic stability of long-span prestressed concrete cable-stayed bridges. (author)

  10. Numerical analysis of dynamic response of vehicle–bridge coupled system on long-span continuous girder bridge

    OpenAIRE

    An, Lipeng; Li, Dejian; Yu, Peng; Yuan, Peng

    2016-01-01

    To systematically study the vehicle–bridge coupled dynamic response and its change rule with different parameters, a vehicle model with seven degrees of freedom was built and the total potential energy of vehicle space vibration system was deduced. Considering the stimulation of road roughness, the dynamic response equation of vehicle–bridge coupled system was established in accordance with the elastic system principle of total potential energy with stationary value and the “set-in-right-posi...

  11. Development of a smart timber bridge girder with fiber optic sensors

    Science.gov (United States)

    James Wacker; Ursula Deza; Brent M. Phares; Terry J. Wipf

    2010-01-01

    Past timber bridge evaluation and maintenance efforts in the USA have principally focused on the internal integrity of timber components using various non-destructive evaluation tools to supplement visual inspection data. This project is part of a comprehensive effort to develop smart structure concepts for improving the long-term performance, maintenance, and...

  12. Study on the Effect and Mechanism of Aerodynamic Measures for the Vortex-Induced Vibration of Separate Pairs of Box Girders in Cable-Stayed Bridges

    Directory of Open Access Journals (Sweden)

    Han Xin He

    2015-01-01

    Full Text Available Although not always resulting in catastrophic failures, vortex-induced vibration (VIV response can seriously impact the fatigue life and functionality of bridges, especially for separate pairs of box girders in cable-stayed bridges. This study investigates the effects of three aerodynamic measures: grating, inclined web plate, and the baffles on separated box girders in the cable-stayed bridges. The experimental result indicates that the grating of different opening ratios can control the vortex-induced vibration effectively, and the optimized grating opening ratio set in this paper is 40%. Increasing the angle of inclined web plate has a great control on mitigation of the vortex-induced vibration. However, there is an optimum angle where the amplitude of vortex-induced vibration is the smallest at low wind speed. The amplitude of vortex-induced vibration becomes larger with the increase of the web inclined angle that exceeds the optimum angle. Comparatively, the baffles installed on both sides of the inclined webs are more effective to restrain the vortex-induced resonance. The Computational Fluent Dynamics (CFD software is utilized to investigate the mechanism of the experimental results.

  13. Effects of CFRP Strengthening on Dynamic and Fatigue Responses of Composite Bridge

    Directory of Open Access Journals (Sweden)

    Kittisak Kuntiyawichai

    2014-01-01

    Full Text Available This paper investigates the effect of CFRP strengthening on dynamic and fatigue responses of composite bridge using finite element program ABAQUS. Dynamic and fatigue responses of composite bridge due to truck load based on AASHTO standard are investigated. Two types of CFRP strengthening techniques, CFRP sheets and CFRP deck, are applied to both the damaged and undamaged bridges. For the case of damaged bridge, two through-thickness crack sizes, 3 mm and 6 mm in depth, are assumed at midspan of the steel girders. Furthermore, effects of the number of steel girders on the dynamic and fatigue responses are also considered. The results show that the maximum responses of composite bridges occur for dual lane cases. By using CFRP as a strengthening material, the maximum stress and deflection of the steel girders reduce and consequently increase the fatigue life of the girders. After introducing initial crack into the steel girders of the composite bridges, the fatigue life of the bridges is dramatically reduced. However, the overall performance of the damaged composite bridge can be improved by using CFRP, albeit with less effectiveness. Therefore, if cracks are found, steel welding must be performed before strengthening the composite bridge by CFRP.

  14. Corrosion processes on weathering steel railway bridge in Prague

    OpenAIRE

    Urban, Viktor; Křivý, Vít; Buchta, Vojtěch

    2016-01-01

    This contribution deals with experimental corrosion tests carried out on the weathering steel railway bridge in Prague. The basic specific property of the weathering steel is an ability to create in favourable environment a protective patina layer on its surface. Since 1968 weathering steel is used under the name “Atmofix” in the Czech Republic and can be used as a standard structural material without any corrosion protection. The weathering steel Atmofix is mostly used for bridge structures ...

  15. Fatigue-Prone Details in Steel Bridges

    Directory of Open Access Journals (Sweden)

    Mohsen Heshmati

    2012-11-01

    Full Text Available This paper reviews the results of a comprehensive investigation including more than 100 fatigue damage cases, reported for steel and composite bridges. The damage cases are categorized according to types of detail. The mechanisms behind fatigue damage in each category are identified and studied. It was found that more than 90% of all reported damage cases are of deformation-induced type and generated by some kind of unintentional or otherwise overlooked interaction between different load-carrying members or systems in the bridge. Poor detailing, with unstiffened gaps and abrupt changes in stiffness at the connections between different members were also found to contribute to fatigue cracking in many details.

  16. Verification of LRFD Bridge Design and Analysis Software for INDOT

    OpenAIRE

    Varma, Amit H.; Seo, Jungil

    2009-01-01

    NCHRP Process 12-50 was implemented to evaluate and verify composite steel I-girder bridge design software used commonly in Indiana. A test-bed of twenty one bridges was developed with the guidance from an Indiana Department of Transportation appointed research advisory panel (RAP). The test-bed included five simple-span and sixteen multi-span bridge superstructures. More than 80 parameters were required to define a bridge and they include bridge span, girder spacing, number of beams, section...

  17. Magnetic-based NDE of steel in prestressed and post-tensioned concrete bridges

    Science.gov (United States)

    Ghorbanpoor, Al

    1998-03-01

    This paper addresses a study, funded by the Federal Highway Administration (FHWA), the U.S. Department of Transportation (DOT), that is currently underway at the University of Wisconsin-Milwaukee. The objective of the study is to develop an automated non-destructive testing system based on the magnetic flux leakage principle that would allow assessment of the condition of reinforcing and prestressing steels in concrete bridge components. Corrosion or cracking of steel within concrete members will be detected and evaluated. The system will be used as a self clamping and moving sensing device that can be installed on a concrete girder. Data from the sensing device is transmitted via a wireless communication system to data recording/analysis equipment on the ground. The sensing device may also be operated manually to allow inspection of local areas such as the end bearing or cable anchorage locations in cable bridges. Through performing a correlation analysis of recorded data, an assessment of the condition of the member under test is made. Reference data base for the correlation analysis is established through laboratory and field testing with known conditions.

  18. A calculation model for the noise from steel railway bridges

    NARCIS (Netherlands)

    Janssens, M.H.A.; Thompson, D.J.

    1996-01-01

    The sound level of a train crossing a steel railway bridge is usually about 10 dB higher than on plain track. In the Netherlands there are many such bridges which, for practical reasons, cannot be replaced by more intrinsically quiet concrete bridges. A computational model is described for the

  19. Repair, strengthening and upgrading of steel bridges in The Netherlands

    NARCIS (Netherlands)

    Snijder, H.H.; Hesselink, B.H.

    2018-01-01

    After World War II, many steel bridges were designed and built in The Netherlands. Many of these bridges are now of a substantial age and were designed for static and fatigue loading less severe than eventually present during their lifetime. Many of these bridges now show (fatigue) damage. Depending

  20. Renovation techniques for fatigue cracked orthotropic steel bridge decks

    NARCIS (Netherlands)

    de Jong, F.B.P.

    2007-01-01

    This dissertation presents the research into renovation techniques for orthotropic steel bridge decks. These techniques are needed to solve fatigue problems in the decks of these bridges, as several fatigue cracks have been detected in the deck structure of these bridges the last decade. A

  1. Concrete-Filled Steel Tube Arch Bridges in China

    Directory of Open Access Journals (Sweden)

    Jielian Zheng

    2018-02-01

    Full Text Available In the past 20 years, great progress has been achieved in China in the construction of concrete-filled steel tube (CFST arch bridges and concrete arch bridges with a CFST skeleton. The span of these bridges has been increasing rapidly, which is rare in the history of bridge development. The large-scale construction of expressways and high-speed railways demands the development of long-span arch bridges, and advances in design and construction techniques have made it possible to construct such bridges. In the present study, the current status, development, and major innovative technologies of CFST arch bridges and concrete arch bridges with a CFST skeleton in China are elaborated. This paper covers the key construction technologies of CFST arch bridges, such as the design, manufacture, and installation of steel tube arch trusses, the preparation and pouring of in-tube concrete, and the construction of the world’s longest CFST arch bridge—the First Hejiang Yangtze River Bridge. The main construction technologies of reinforced concrete arch bridges are also presented, which include cable-stayed fastening-hanging cantilever assembly, adjusting the load by means of stay cables, surrounding the concrete for arch rib pouring, and so forth. In addition, the construction of two CFST skeleton concrete arch bridges—the Guangxi Yongning Yong River Bridge and the Yunnan–Guangxi Railway Nanpan River Bridge—is discussed. CFST arch bridges in China have already gained a world-leading position; with the continuous innovation of key technologies, China will become the new leader in promoting the development of arch bridges. Keywords: Concrete-filled steel tube (CFST arch bridge, Steel-reinforced concrete arch bridge, Cable-stayed fastening-hanging cantilever assembly, Vacuum-assisted pouring in-tube concrete, Adjusting load by stay cables

  2. Optimal, Generic Planning of Maintenance and Inspection of Steel Bridges

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Faber, Michael Havbro

    2002-01-01

    Fatigue damage is an important deterioration mechanism for steel bridges. This paper describes a simplified and generic approach for reliability and risk based inspection planning of fatigue sensitive structural details. Fatigue sensitive details are categorized according to their loading charact...

  3. Developing Extended Strands in Girder-Cap Beam Connections for Positive Moment Resistance

    Science.gov (United States)

    2017-11-01

    In bridges constructed with precast prestressed concrete girders, resistance to seismic effects is achieved by the interaction between the columns, the cap beam and the girders. These components must be connected to provide flexural resistance. Under...

  4. Implementation and field evaluation of pretensioned concrete girder end crack control.

    Science.gov (United States)

    2016-05-01

    Wisconsin bulb tee pretensioned concrete girders are currently used for bridge construction. Their efficiency in load resistance has made them particularly desirable. To provide that efficiency, these girders are heavily prestressed. Cracking is evid...

  5. Special heavy plates and steel solutions for bridge building

    Science.gov (United States)

    Lehnert, Tobias

    2017-09-01

    In many European countries infrastructure, -road as well as railway infrastructure-, needs intensive investments to follow the growing demands of mobility and goods traffic. Steel or steel composite bridges offer in this context viable and very sustainable solutions. Due to its unlimited recyclability steel can in general be seen as the ideal material for such sustainable constructions, but especially when designers or fabricators exploit the nowadays available possibilities of steel industry very cost-efficient and remarkable constructions are realizable. This paper will highlight some of these newest developments in heavy plates for bridge building. For example, for small span railway bridges the so-called thick plate trough bridges have proven to be a favourable concept. Very heavy plates with single plate weights up to 42 t allow building these bridges very efficiently out of one or very few single plates. Another interesting development is the so-called longitudinally profiled plates which allow a varying plate thickness along the actual loading profile. As last point the rising entry of higher strength steels in bridge building will be discussed and it will be shown why thermomechanically rolled plates are the ideal solution for these demands.

  6. Economic impact of multi-span, prestressed concrete girder bridges designed as simple span versus continuous span : final report.

    Science.gov (United States)

    2016-10-01

    The objective of this study was to determine the economic impact of designing pre-tensioned prestressed concrete beam (PPCB) : bridges utilizing the continuity developed in the bridge deck as opposed to the current Iowa Department of Transportation (...

  7. Economic impact of multi-span, prestressed concrete girder bridges designed as simple span versus continuous span : tech transfer summary.

    Science.gov (United States)

    2016-10-01

    The objective of this study was to determine the economic impact of : designing pre-tensioned prestressed concrete beam (PPCB) bridges : utilizing the continuity developed in the bridge deck as opposed to the : current Iowa Department of Transportati...

  8. Hybrid FRP-concrete bridge deck system final report II : long term performance of hybrid FRP-concrete bridge deck system.

    Science.gov (United States)

    2009-06-01

    This report describes the investigation of the long term structural performance of a : hybrid FRP-concrete (HFRPC) bridge deck on steel girders. The study aimed at : assessing three long term aspects pertaining to the HFRPC bridge deck: (1) creep : c...

  9. A case study of interior low-frequency noise from box-shaped bridge girders induced by running trains: Its mechanism, prediction and countermeasures

    Science.gov (United States)

    Zhang, Xun; Li, Xiaozhen; Hao, Hong; Wang, Dangxiong; Li, Yadong

    2016-04-01

    A side effect of high-speed railway and urban rail transit systems is the associated vibration and noise. Since the use of concrete viaducts is predominant in railway construction due to scarce land resources, low-frequency (20-200 Hz) structure-radiated noise from concrete bridges is a principal concern. Although it is the most commonly used bridge type, the mechanism of noise emission from box-shaped bridge girders when subjected to impact forces from moving trains, which sounds like beating a drum, has not been well studied. In this study, a field measurement was first made on a simply-supported box-shaped bridge to record the acceleration of the slabs and the associated sound pressures induced by running trains. These data indicated that a significant beat-wave noise occurred in the box-shaped cavity when the train speed was around 340 km/h, which arose from the interference between two sound waves of 75.0 Hz and 78.8 Hz. The noise leakage from the bridge expansion joint was serious and resulted in obvious noise pollution near the bridge once the beat-wave noise was generated in the cavity. The dominant frequency of the interior noise at 75.0 Hz was confirmed from the spectrum of the data and the modal analysis results, and originated from the peak vibration of the top slab due to resonance and the first-order vertical acoustic mode, which led to cavity resonance, amplifying the corresponding noise. The three-dimensional acoustic modes and local vibration modes of the slab were calculated by using the finite element method. A simplified vehicle-track-bridge coupling vibration model was then developed to calculate the wheel-rail interaction force in a frequency range of 20-200 Hz. Numerical simulations using the boundary element method confirmed the cavity resonance effect and the numerical results agreed well with the data. Based on the calibrated numerical model, three noise reduction measures, i.e., adding a horizontal baffle in the interior cavity, narrowing

  10. The Damage Effects in Steel Bridges under Highway Random Loading

    DEFF Research Database (Denmark)

    Agerskov, Henning; Nielsen, Jette Andkjær

    1996-01-01

    In the present investigation, fatigue damage accumulation in steel bridges under highway random loading is studied. In the experimental part of the investigation, fatigue test series on welded plate test specimens have been carried through. The fatigue tests have been carried out using load histo...... indicate that the linear fatigue damage accumulation formula, which is normally used in the design against fatigue in steel bridges, may give results, which are unconservative.......In the present investigation, fatigue damage accumulation in steel bridges under highway random loading is studied. In the experimental part of the investigation, fatigue test series on welded plate test specimens have been carried through. The fatigue tests have been carried out using load...

  11. The fatigue behaviour of the breathing webs of steel bridge girders

    Czech Academy of Sciences Publication Activity Database

    Škaloud, Miroslav; Zörnerová, Marie

    2005-01-01

    Roč. 11, č. 4 (2005), s. 323-336 ISSN 1392-3730 R&D Projects: GA ČR(CZ) GA103/05/2059 Institutional research plan: CEZ:AV0Z20710524 Keywords : repeated loads * fatigue crack * S-N curves Subject RIV: JM - Building Engineering

  12. Assessment of vehicular live load and load factors for design of short-span bridges according to the new Egyptian Code

    Directory of Open Access Journals (Sweden)

    Hatem M. Seliem

    2015-04-01

    The study shows that concrete box-girders designed according to ECP-201:2012 and ECP-201:2003 using the ultimate limit state method yield almost the same demand. Despite the increase in the VLL of ECP-201:2012, and consequently the live load forces, concrete I-shaped girder bridges will be subjected to less total factored internal forces in comparison to ECP-201:2003 This is attributed to the interaction between the live to dead loads ratio and the load combinations. Design of composite steel plate girder bridges according to ECP-201:2012 using the allowable stress design method yields over designed sections.

  13. Fatigue in Steel Highway Bridges under Random Loading

    DEFF Research Database (Denmark)

    Agerskov, Henning; Nielsen, J.A.; Vejrum, Tina

    1997-01-01

    on welded plate test specimens have been carried through. The materials that have been used are either conventional structural steel with a yield stress of ~ 400-410 MPa or high-strength steel with a yield stress of ~ 810-840 MPa.The fatigue tests have been carried out using load histories, which correspond......In the present investigation, fatigue damage accumulation in steel highway bridges under random loading is studied. The fatigue life of welded joints has been determined both experimentally and from a fracture mechanics analysis.In the experimental part of the investigation, fatigue test series...... to one week's traffic loading, determined by means of strain gage measurements on the orthotropic steel deck structure of the Farø Bridges in Denmark.The test series which have been carried through show a significant difference between constant amplitude and variable amplitude fatigue test results. Both...

  14. Fatigue in Steel Highway Bridges under Random Loading

    DEFF Research Database (Denmark)

    Agerskov, Henning; Nielsen, Jette Andkjær

    1999-01-01

    have been carried through. The materials that have been used are either conventional structural steel with a yield stress of f(y) similar to 400-410 MPa or high-strength steel with a yield stress of f(y) similar to 810-840 MPa. The fatigue tests have been carried out using load histories, which......Fatigue damage accumulation in steel highway bridges under random loading is studied. The fatigue life of welded joints has been determined both experimentally and from a fracture mechanics analysis. In the experimental part of the investigation, fatigue test series on welded plate test specimens...... correspond to one week's traffic loading, determined by means of strain gauge measurements on the orthotropic steel deck structure of the Faro Bridges in Denmark. The test series carried through show a significant difference between constant amplitude and variable amplitude fatigue test results. Both...

  15. Design and evaluation of steel bridges with double composite action

    Science.gov (United States)

    2010-02-01

    This report presents findings from a cooperative USF/URS/FDOT research study undertaken to develop design rules for : double composite steel bridges. In the study, a 48 ft long, 16 ft wide, 4 ft. 10 in. deep trapezoidal HPS 70W box section : desig...

  16. Experimental investigation on FRP to steel adhesively-bonded joint under tensile loading

    NARCIS (Netherlands)

    Jiang, X.; Kolstein, M.H.; Bijlaard, F.S.K.

    2012-01-01

    Due to various advantages of Fibre-Reinforced Polymer (FRP) decks, the FRP to steel composite girder system is being increasingly used in the construction of new bridges as well as the rehabilitation projects of old bridges. This paper focus on the mechanical behaviors and failure modes of the

  17. Dragon bridge - the world largest dragon-shaped (ARCH steel bridge as element of smart city

    Directory of Open Access Journals (Sweden)

    Chinh Luong Minh

    2016-01-01

    Full Text Available Dragon Bridge - The world’s largest dragon-shaped steel bridge, with an installation cost of $85 million USD, features 6 lanes for two separate directions, 666 meters of undulating steel in the shape of a dragon in the Ly Dynasty, the symbol of prosperity in Vietnamese culture. This unique and beautifully lit bridge, which also breathes fire and sprays water. It’s the purposeful integration of the lighting hardware articulates the dragon’s form, and the fire-breathing dragon head. This project transcends the notion of monumental bridge with dynamic colour-changing lighting, creating an iconic sculpture in the skyline that is both reverent and whimsical. The signature feature of the bridge was the massive undulating support structure resembling a dragon flying over the river. The dragon is prominent in Vietnamese culture as a symbol of power and nobility. Dragon Bridge stands out as a model of innovation. It has received worldwide attention in the design community and from the global media for its unique arch support system. Dragon Bridge serves as an example of how aesthetic quality of a design can serve cultural, economic and functional purposes. The article presents design solutions of the object and the evaluation of the technical condition before putting the facility into service.

  18. Determination of in-situ strength on selected bridge element concrete girder and slab of Nagtahan bridge using rebound hammer test

    International Nuclear Information System (INIS)

    Uy, Bernadette Betsy B.; Banaga, Renato T.

    2013-01-01

    This study examined the extent of the damage due to fire on the affected areas of the bridge structure. The need to assess the damage of the Nagtahan Bridge is very useful to provide appropriate measures in the repair or in the reinforcement of the bridge, hence will ensure its strength and integrity. The study included two (2) spans of the bridge deck/slab with specific locations of the bridge that were subjected for testing. The Rebound Hammer was used as a preliminary test in evaluating the bridge condition. Its capability is to assess the in-place uniformity of concrete, to delineate regions in a structure of poor quality or deteriorated concrete, and to estimate the in-place strength; and ultimately, for relative comparison between the different structures of the bridge. With the use of the NDT Rebound Hammer Test, the researchers were able to determine whether or not the in-situ strength of the bridge's concrete has been weakened due to fire. The DPW-Standard Specification is the government acceptable manual, containing the acceptance criteria, used as the basis for standard construction procedures in the department.(author)

  19. Evaluation of continuity detail for precast prestressed girders.

    Science.gov (United States)

    2011-08-01

    The construction of highway bridges using precast prestressed concrete (PSC) girders is considered one of the most : economical construction alternatives because of the advantages they offer (e.g. reducing formwork and rapid construction). : Construc...

  20. Evaluation of continuity detail for precast prestressed girders : tech summary.

    Science.gov (United States)

    2011-08-01

    Building multi-simple span bridges using precast prestressed concrete girders is an easy construction. However, the existence of : expansion joints often leads to a host of problems in their vicinity due to drainage leaks. Furthermore, debris accumul...

  1. Development of guidelines for transportation of long prestressed concrete girders.

    Science.gov (United States)

    2016-12-01

    This research study investigates the behavior of two long prestressed concrete girders during lifting and : transportation from the precast yard to the bridge site, with a particular focus on cracking concerns : during transport. Different response m...

  2. Failure and fatigue life assessment of steel railway bridges with brittle material

    NARCIS (Netherlands)

    Maljaars, J.

    2014-01-01

    Some existing steel bridges have been constructed from steels with a toughness that does not fulfil the requirements in modern standards. In such a case, standards for bridges do not provide an alternative assessment route. Yet such bridges may still be fit for purpose. This paper presents an

  3. Mechanism of Fatigue Crack Growth of Bridge Steel Structures

    Directory of Open Access Journals (Sweden)

    Zhu H.

    2016-12-01

    Full Text Available This study was carried out on the background of Sutong Bridge project based on fracture mechanics, aiming at analyzing the growth mechanism of fatigue cracks of a bridge under the load of vehicles. Stress intensity factor (SIF can be calculated by various methods. Three steel plates with different kinds of cracks were taken as the samples in this study. With the combination of finite element analysis software ABAQUS and the J integral method, SIF values of the samples were calculated. After that, the extended finite element method in the simulation of fatigue crack growth was introduced, and the simulation of crack growth paths under different external loads was analyzed. At last, we took a partial model from the Sutong Bridge and supposed its two dangerous parts already had fine cracks; then simulative vehicle load was added onto the U-rib to predict crack growth paths using the extended finite element method.

  4. 77 FR 54652 - Draft Program Comment for Common Post-1945 Concrete and Steel Bridges

    Science.gov (United States)

    2012-09-05

    ... constructed by State transportation agencies after 1945, using reinforced concrete or steel beams and designs... proposed Program Comment: Program Comment for Common Post-1945 Concrete and Steel Bridges I. Introduction... reinforced concrete or steel beams and designs that quickly became standardized. These common bridge types...

  5. DISTORTION ANALYSIS OF TILL -WALLED BOX GIRDERS

    African Journals Online (AJOL)

    NIJOTECH

    bridges, buildings, motor vehicles, ships and aircrafts. Due to thinness of the box walls, generalized loads applied to this structure give rise to warping and distortion of ..... Recommendation for Design of. Intermediate Diaphragms in Box. Girders, Transactions of Japanese. Society of Civil Engineers, Vol. 14,1984, pp 121-126.

  6. Skewed steel bridges, part ii : cross-frame and connection design to ensure brace effectiveness : technical summary.

    Science.gov (United States)

    2017-08-01

    Skewed bridges in Kansas are often designed such that the cross-frames are carried parallel to the skew angle up to 40, while many other states place cross-frames perpendicular to the girder for skew angles greater than 20. Skewed-parallel cross-...

  7. Skewed steel bridges, part ii : cross-frame and connection design to ensure brace effectiveness : final report.

    Science.gov (United States)

    2017-08-01

    Skewed bridges in Kansas are often designed such that the cross-frames are carried parallel to the skew angle up to 40, while many other states place cross-frames perpendicular to the girder for skew angles greater than 20. Skewed-parallel cross-...

  8. Numerical investigation into thermal load responses of steel railway bridge

    Science.gov (United States)

    Saravana Raja Mohan, K.; Sreemathy, J. R.; Saravanan, U.

    2017-07-01

    Bridge design requires consideration of the effects produced by temperature variations and the resultant thermal gradients in the structure. Temperature fluctuation leads to expansion and contraction of bridges and these movements are taken care by providing expansion joints and bearings. Free movements of a member can be restrained by imposing certain boundary condition but at the same time considerable allowances should be made for the stresses resulting from this restrained condition since the additional deformations and stresses produced may affect the ultimate and serviceability limit states of the structure. If the reaction force generated by the restraints is very large, then its omission can lead to unsafe design. The principal objective of this research is to study the effects of temperature variation on stresses and deflection in a steel railway bridge. A numerical model, based on finite element analysis is presented for evaluating the thermal performance of the bridge. The selected bridge is analyzed and the temperature field distribution and the corresponding thermal stresses and strains are calculated using the finite element software ABAQUS. A thorough understanding of the thermal load responses of a structure will result in safer and dependable design practices.

  9. Bridges analysis, design, structural health monitoring, and rehabilitation

    CERN Document Server

    Bakht, Baidar

    2015-01-01

    This book offers a valuable guide for practicing bridge engineers and graduate students in structural engineering; its main purpose is to present the latest concepts in bridge engineering in fairly easy-to-follow terms. The book provides details of easy-to-use computer programs for: ·      Analysing slab-on-girder bridges for live load distribution. ·      Analysing slab and other solid bridge components for live load distribution. ·      Analysing and designing concrete deck slab overhangs of girder bridges under vehicular loads. ·      Determining the failure loads of concrete deck slabs of girder bridges under concentrated wheel loads. In addition, the book includes extensive chapters dealing with the design of wood bridges and soil-steel bridges. Further, a unique chapter on structural health monitoring (SHM) will help bridge engineers determine the actual load carrying capacities of bridges, as opposed to their perceived analytical capacities. The chapter addressing structures...

  10. Experimental assessment of an RFID-based crack sensor for steel structures

    Science.gov (United States)

    E Martínez-Castro, R.; Jang, S.; Nicholas, J.; Bansal, R.

    2017-08-01

    The use of welded steel cover plates had been a common design practice to increase beam section capacity in regions of high moment for decades. Many steel girder bridges with cover plates are still in service. Steel girder bridges are subject to cyclic loading, which can initiate crack formation at the toe of the weld and reduce beam capacity. Thus, timely detection of fatigue cracks is of utmost importance in steel girder bridge monitoring. To date, crack monitoring methods using in-house radio frequency identification (RFID)-based sensors have been developed to complement visual inspection and provide quantitative information of damage level. Offering similar properties at a reduced cost, commercial ultra-high frequency (UHF) passive RFID tags have been identified as a more financially viable option for pervasive crack monitoring using a dense array of sensors. This paper presents a study on damage sensitivity of low-cost commercial UHF RFID tags for crack detection and monitoring on metallic structures. Using backscatter power as a parameter for damage identification, a crack sensing system has been developed for single and multiple tag configurations for increased sensing pervasiveness. The effect on backscatter power of the existence and stage of crack propagation has been successfully characterized. For further automation of crack detection, a damage index based on the variation of backscatter power has also been established. The tested commercial RFID-based crack sensor contributes to the usage of this technology on steel girder bridges.

  11. Application of Classical Land Surveying Measurement Methods for Determining the Vertical Displacement of Railway Bridges

    Science.gov (United States)

    Gawronek, Pelagia; Makuch, Maria

    2017-12-01

    The classical measurements of stability of railway bridge, in the context of determining the vertical displacements of the object, consisted on precise leveling of girders and trigonometric leveling of controlled points (fixed into girders' surface). The construction elements, which were measured in two ways, in real terms belonged to the same vertical planes. Altitude measurements of construction were carried out during periodic structural stability tests and during static load tests of bridge by train. The specificity of displacement measurements, the type of measured object and the rail land surveying measurement conditions were determinants to define methodology of altitude measurement. The article presents compatibility of vertical displacements of steel railway bridge, which were developed in two measurement methods. In conclusion, the authors proposed the optimum concept of determining the vertical displacements of girders by using precise and trigonometric leveling (in terms of accuracy, safety and economy of measurement).

  12. Application of Classical Land Surveying Measurement Methods for Determining the Vertical Displacement of Railway Bridges

    Directory of Open Access Journals (Sweden)

    Gawronek Pelagia

    2017-12-01

    Full Text Available The classical measurements of stability of railway bridge, in the context of determining the vertical displacements of the object, consisted on precise leveling of girders and trigonometric leveling of controlled points (fixed into girders' surface. The construction elements, which were measured in two ways, in real terms belonged to the same vertical planes. Altitude measurements of construction were carried out during periodic structural stability tests and during static load tests of bridge by train. The specificity of displacement measurements, the type of measured object and the rail land surveying measurement conditions were determinants to define methodology of altitude measurement. The article presents compatibility of vertical displacements of steel railway bridge, which were developed in two measurement methods. In conclusion, the authors proposed the optimum concept of determining the vertical displacements of girders by using precise and trigonometric leveling (in terms of accuracy, safety and economy of measurement.

  13. Monitoring system of arch bridge for safety network management

    Science.gov (United States)

    Joo, Bong Chul; Yoo, Young Jun; Lee, Chin Hyung; Park, Ki Tae; Hwang, Yoon Koog

    2010-03-01

    Korea has constructed the safety management network monitoring test systems for the civil infrastructure since 2006 which includes airport structure, irrigation structure, railroad structure, road structure, and underground structure. Bridges among the road structure include the various superstructure types which are Steel box girder bridge, suspension bridge, PSC-box-girder bridge, and arch bridge. This paper shows the process of constructing the real-time monitoring system for the arch bridge and the measured result by the system. The arch type among various superstructure types has not only the structural efficiency but the visual beauty, because the arch type superstructure makes full use of the feature of curve. The main measuring points of arch bridges composited by curved members make a difference to compare with the system of girder bridges composited by straight members. This paper also shows the method to construct the monitoring system that considers the characteristic of the arch bridge. The system now includes strain gauges and thermometers, and it will include various sensor types such as CCTV, accelerometers and so on additionally. For the long term and accuracy monitoring, the latest optical sensors and equipments are applied to the system.

  14. Structural health monitoring in end-of-life prediction for steel bridges subjected to fatigue cracking

    NARCIS (Netherlands)

    Attema, T.; Courage, W.M.G.; Maljaars, J.; Meerveld, H. van; Paulissen, J.H.; Pijpers, R.J.M.; Slobbe, A.T.

    2015-01-01

    This paper presents a monitoring and modelling methodology to assess the current and future conditions of steel bridges subjected to fatigue cracking. Steel bridges are subjected to fatigue cracking as a result of fluctuating stresses caused by the crossing of heavy vehicles. Specifically for

  15. Application of Composite Structures in Bridge Engineering. Problems of Construction Process and Strength Analysis

    Science.gov (United States)

    Flaga, Kazimierz; Furtak, Kazimierz

    2015-03-01

    Steel-concrete composite structures have been used in bridge engineering from decades. This is due to rational utilisation of the strength properties of the two materials. At the same time, the reinforced concrete (or prestressed) deck slab is more favourable than the orthotropic steel plate used in steel bridges (higher mass, better vibration damping, longer life). The most commonly found in practice are composite girder bridges, particularly in highway bridges of small and medium spans, but the spans may reach over 200 m. In larger spans steel truss girders are applied. Bridge composite structures are also employed in cable-stayed bridge decks of the main girder spans of the order of 600, 800 m. The aim of the article is to present the cionstruction process and strength analysis problems concerning of this type of structures. Much attention is paid to the design and calculation of the shear connectors characteristic for the discussed objects. The authors focused mainly on the issues of single composite structures. The effect of assembly states on the stresses and strains in composite members are highlighted. A separate part of problems is devoted to the influence of rheological factors, i.e. concrete shrinkage and creep, as well as thermal factors on the stresses and strains and redistribution of internal forces.

  16. Strain features and condition assessment of orthotropic steel deck cable-supported bridges subjected to vehicle loads by using dense FBG strain sensors

    Science.gov (United States)

    Wei, Shiyin; Zhang, Zhaohui; Li, Shunlong; Li, Hui

    2017-10-01

    Strain is a direct indicator of structural safety. Therefore, strain sensors have been used in most structural health monitoring systems for bridges. However, until now, the investigation of strain response has been insufficient. This paper conducts a comprehensive study of the strain features of the U ribs and transverse diaphragm on an orthotropic steel deck and proposes a statistical paradigm for crack detection based on the features of vehicle-induced strain response by using the densely distributed optic fibre Bragg grating (FBG) strain sensors. The local feature of strain under vehicle load is highlighted, which enables the use of measurement data to determine the vehicle loading event and to make a decision regarding the health status of a girder near the strain sensors via technical elimination of the load information. Time-frequency analysis shows that the strain contains three features: the long-term trend item, the short-term trend item, and the instantaneous vehicle-induced item (IVII). The IVII is the wheel-induced strain with a remarkable local feature, and the measured wheel-induced strain is only influenced by the vehicle near the FBG sensor, while other vehicles slightly farther away have no effect on the wheel-induced strain. This causes the local strain series, among the FBG strain sensors in the same transverse locations of different cross-sections, to present similarities in shape to some extent and presents a time delay in successive order along the driving direction. Therefore, the strain series induced by an identical vehicle can be easily tracked and compared by extracting the amplitude and calculating the mutual ratio to eliminate vehicle loading information, leaving the girder information alone. The statistical paradigm for crack detection is finally proposed, and the detection accuracy is then validated by using dense FBG strain sensors on a long-span suspension bridge in China.

  17. Numerical/experimental research on welded joints in aluminium truss girders

    NARCIS (Netherlands)

    van Hove, B.W.E.M.; Soetens, F.; Mazzolani, F.M.; Bellucci, F.; Faggiano, B.; Squillace, A.

    2016-01-01

    Welded joints in a 30 meter span aluminium truss girder were investigated numerically and experimentally. Since aluminium design rules for welded K-and N-joints in CHS truss girders were lacking the joints were checked using steel design rules. Calculations showed that the N-joints were governing

  18. Prestressing force monitoring method for a box girder through distributed long-gauge FBG sensors

    Science.gov (United States)

    Chen, Shi-Zhi; Wu, Gang; Xing, Tuo; Feng, De-Cheng

    2018-01-01

    Monitoring prestressing forces is essential for prestressed concrete box girder bridges. However, the current monitoring methods used for prestressing force were not applicable for a box girder neither because of the sensor’s setup being constrained or shear lag effect not being properly considered. Through combining with the previous analysis model of shear lag effect in the box girder, this paper proposed an indirect monitoring method for on-site determination of prestressing force in a concrete box girder utilizing the distributed long-gauge fiber Bragg grating sensor. The performance of this method was initially verified using numerical simulation for three different distribution forms of prestressing tendons. Then, an experiment involving two concrete box girders was conducted to study the feasibility of this method under different prestressing levels preliminarily. The results of both numerical simulation and lab experiment validated this method’s practicability in a box girder.

  19. Active Control of Suspension Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper some recent research on active control of very long suspension bridges, is presented. The presentation is based on research work at Aalborg University, Denmark. The active control system is based on movable flaps attached to the bridge girder. Wind load on bridges with or without...... flaps attached to the girder is briefly presented. A simple active control system is discussed. Results from wind tunnel experiments with a bridge section show that flaps can be used effectively to control bridge girder vibrations. Flutter conditions for suspension bridges with and without flaps...

  20. Analysis on Adhesively-Bonded Joints of FRP-steel Composite Bridge under Combined Loading: Arcan Test Study and Numerical Modeling

    Directory of Open Access Journals (Sweden)

    Xu Jiang

    2016-01-01

    Full Text Available The research presented in this paper is an experimental study and numerical analysis on mechanical behavior of the adhesively-bonded joint between FRP sandwich bridge deck and steel girder. Generally, there are three typical stress states in the adhesively-bonded joint: shear stress, tensile stress, and combination of both. To realize these stress states in the adhesively-bonded joint during tests, a specific loading device is developed with the capacity of providing six different loading angles, which are 0°(pure tension, 18°, 36°, 54°, 72° and 90°(pure shear. Failure modes of adhesively-bonded joints are investigated. It indicates that, for the pure shear loading, the failure mode is the cohesive failure (near the interface between the adhesive layer and the steel support in the adhesive layer. For the pure tensile and combined loading conditions, the failure mode is the combination of fiber breaking, FRP delamination and interfacial adhesion failure between the FRP sandwich deck and the adhesive layer. The load-bearing capacities of adhesive joints under combined loading are much lower than those of the pure tensile and pure shear loading conditions. According to the test results of six angle loading conditions, a tensile/shear failure criterion of the adhesively-bonded joint is obtained. By using Finite Element (FE modeling method, linear elastic simulations are performed to characterize the stress distribution throughout the adhesively-bonded joint.

  1. Laser welded steel sandwich panel bridge deck development : finite element analysis and stake weld strength tests.

    Science.gov (United States)

    2009-09-01

    This report summarizes the analysis of laser welded steel sandwich panels for use in bridge structures and : static testing of laser stake welded lap shear coupons. Steel sandwich panels consist of two face sheets : connected by a relatively low-dens...

  2. Design and construction of the Natorigawa Bridge; Natorigawa kyoryo no sekkei/seko

    Energy Technology Data Exchange (ETDEWEB)

    Murai, Y.; Oba, M.; Omurata, Y. [JR East Japan Railway Co., Tokyo (Japan); Miyauchi, M.; Iwasaki, I. [Taisei Corp., Tokyo (Japan)

    1997-03-31

    The Natorigawa Bridge is reconstructed. Out of the reconstruction work, a report is made mainly on the design of the superstructure work of the PC panel-stayed bridge and the details of the work. In selecting bridge type, PC simple through beam bridge, steel trussed bridge, PC cable-stayed bridge, and PC panel-stayed bridge are compared, and a 2-span continuous PC panel-stayed bridge is adopted. Its appearance resembles that of the cable-stayed bridge, but the structure resembles a girder bridge. The appropriate span length is the intermediate range between those of the girder bridge and the cable-stayed bridge. Its trafficability is excellent with little deformation by the running of trains because the main beam, diagonal panel, and the main tower are connected rigidly to provide high rigidity of the entire bridge. PRC structure is employed in consideration of the restriction to beam height and economical efficiency. Analyses by a FEM model using two dimensional plane elements and by a few plane frame models as well as comparison of sectional force are performed for this bridge, and a proper plane model is selected. Substructure work, superstructure work and measurement work are described. 3 refs., 16 figs., 6 tabs.

  3. Multidisciplinary health monitoring of a steel bridge deck structure

    NARCIS (Netherlands)

    Pahlavan, P.L.; Pijpers, R.J.M.; Paulissen, J.H.; Hakkesteegt, H.C.; Jansen, T.H.

    2013-01-01

    Fatigue cracks in orthotropic bridge decks are an important cause for the necessary renovation of existing bridges. Parallel utilization of various technologies based on different physical sensing principles can potentially maximize the efficiency of structural health monitoring (SHM) systems for

  4. Construction Simulation Analysis of 60m-span Concrete Filled Steel Tube arch bridge

    Science.gov (United States)

    Shi, Jing Xian; Ding, Qing Hua

    2018-06-01

    The construction process of the CFST arch bridge is complicated. The construction process not only affects the structural stress in the installation, but also determines the form a bridge and internal force of the bridge. In this paper, a 60m span concrete filled steel tube tied arch bridge is taken as the background, and a three-dimensional finite element simulation model is established by using the MIDAS/Civil bridge structure analysis software. The elevation of the main arch ring, the beam stress, the forces in hanger rods and the modal frequency of the main arch during the construction stage are calculated, and the construction process is simulated and analyzed. Effectively and reasonably guide the construction and ensure that the line and force conditions of the completed bridge meet the design requirements and provides a reliable technical guarantee for the safe construction of the bridge.

  5. Vertical impedance measurements on concrete bridge decks for assessing susceptibility of reinforcing steel to corrosion

    Science.gov (United States)

    Bartholomew, Paul D.; Guthrie, W. Spencer; Mazzeo, Brian A.

    2012-08-01

    Corrosion is a pressing problem for aging concrete infrastructure, especially bridge decks. Because of its sensitivity to factors that affect corrosion of reinforcing steel in concrete, resistivity is an important structural health indicator for reinforced concrete structures. In this research, an instrument was developed to measure vertical impedance on concrete bridge decks. Measurements of vertical impedance on slabs prepared in the laboratory, on slabs removed from decommissioned bridge decks, and on an in-service bridge deck in the field demonstrate the utility of the new apparatus.

  6. Influence of microclimate on the sustainability and reliability of weathering steel bridge

    Science.gov (United States)

    Kubzova, M.; Krivy, V.; Kreislova, K.

    2018-04-01

    Reliability and sustainability of bridge structures designed from weathering steel are influenced by the development of a sufficiently protective layer of corrosion products on its surface. The development of this protective layer is affected by several parameters such as air pollution around the bridge structure, the microclimate under the bridge, the location of surface within the bridge structure and the time of wetness. Design of structural details also significantly influences the development of the protective corrosion layer. The article deals with the results of the experimental tests carried out on the road bridge located in the city of Ostrava in the Czech Republic. The development of the protective corrosion layer on the surface of the bridge is significantly influenced by the intensive traffic under the bridge construction and the design solution of the bridge itself. Attention is focused mainly on the influence of chloride deposition on the protective function of the corrosion layer. Corrosion samples were placed on the bridge to evaluate the influence of the above-mentioned parameters. The deposition rate of chlorides spreading from the road to surfaces of the steel structure is also measured.

  7. STRENGTHENING OF A REINFORCED CONCRETE BRIDGE WITH PRESTRESSED STEEL WIRE ROPES

    Directory of Open Access Journals (Sweden)

    Kexin Zhang

    2017-10-01

    Full Text Available This paper describes prestressed steel wire ropes as a way to strengthen a 20-year-old RC T-beam bridge. High strength, low relaxation steel wire ropes with minor radius, high tensile strain and good corrosion resistance were used in this reinforcement. The construction process for strengthening with prestressed steel wire ropes—including wire rope measuring, extruding anchor heads making, anchorage installing, tensioning steel wire ropes and pouring mortar was described. Ultimate bearing capacity of the bridge after strengthening was discussed based on the concrete structure theory. The flexural strength of RC T-beam bridges strengthened with prestressed steel wire ropes was governed by the failure of concrete crushing. To investigate effectiveness of the strengthening method, fielding-load tests were carried out before and after strengthening. The results of concrete strain and deflection show that the flexural strength and stiffness of the strengthened beam are improved. The crack width measurement also indicates that this technique could increase the durability of the bridge. Thus, this strengthened way with prestressed steel wire rope is feasible and effective.

  8. Yonjung High-Speed Railway Bridge Assessment Using Output-Only Structural Health Monitoring Measurements under Train Speed Changing

    Directory of Open Access Journals (Sweden)

    Mosbeh R. Kaloop

    2016-01-01

    Full Text Available Yonjung Bridge is a hybrid multispan bridge that is designed to transport high-speed trains (HEMU-430X with maximum operating speed of 430 km/h. The bridge consists of simply supported prestressed concrete (PSC and composite steel girders to carry double railway tracks. The structural health monitoring system (SHM is designed and installed to investigate and assess the performance of the bridge in terms of acceleration and deformation measurements under different speeds of the passing train. The SHM measurements are investigated in both time and frequency domains; in addition, several identification models are examined to assess the performance of the bridge. The drawn conclusions show that the maximum deflection and acceleration of the bridge are within the design limits that are specified by the Korean and European codes. The parameters evaluation of the model identification depicts the quasistatic and dynamic deformations of PSC and steel girders to be different and less correlated when higher speeds of the passing trains are considered. Finally, the variation of the frequency content of the dynamic deformations of the girders is negligible when high speeds are considered.

  9. Structure-borne noise of railway composite bridge: Numerical simulation and experimental validation

    Science.gov (United States)

    Li, Xiaozhen; Liu, Quanmin; Pei, Shiling; Song, Lizhong; Zhang, Xun

    2015-09-01

    In order to investigate the characteristics of the noise from steel-concrete composite bridges under high-speed train loading, a model used to predict the bridge-borne noise is established and validated through a field experiment. The numerical model for noise prediction is developed based on the combination of spatial train-track-bridge coupled vibration theory and Statistical Energy Analysis (SEA). Firstly, train-track-bridge coupled vibration is adopted to obtain the velocity time history of the bridge deck vibration. Then, the velocity time history is transferred into frequency domain through FFT to serve as the vibratory energy of SEA deck subsystems. Finally, the transmission of the vibratory energy is obtained by solving the energy balance equations of SEA, and the sound radiation is computed using the vibro-acoustic theory. The numerically computed noise level is verified by a field measurement. It is determined that the dominant frequency of steel-concrete composite bridge-borne noise is 20-1000 Hz. The noise from the bottom flange of steel longitudinal girder is less than other components in the whole frequency bands, while the noise from web of steel longitudinal girder is dominant in high frequency range above 315 Hz. The noise from concrete deck dominates in low-frequency domain ranges from 80 Hz to 160 Hz.

  10. Determination of brace forces caused by construction loads and wind loads during bridge construction : [summary].

    Science.gov (United States)

    2014-04-01

    Bridges are constructed in stages as pilings, : columns, girders, decks, and other components : are added. At each stage, the structure must be : stable. Girders, which add significant weight to : the developing structure, rest on elastomeric : beari...

  11. Research on construction technology for orthotropic steel deck pavement of Haihe River Chunyi Bridge

    Science.gov (United States)

    Xue, Y. C.; Qian, Z. D.; Zhang, M.

    2017-01-01

    In order to ensure the good service quality of orthotropic steel deck pavement of Haihe River Chunyi Bridge in Tianjin, and to reduce the occurrence of pavement diseases like lateral and longitudinal cracks, the key working procedures such as steel deck cleaning, anticorrosive coating, bonding layer spraying, seam cutting, epoxy asphalt concrete’s mixing, transportation, paving and compaction were studied. The study was based on the main features of epoxy asphalt concrete which is the pavement materials of Haihe River Chunyi Bridge, and combined with the basic characteristics and construction conditions of Haihe River Chunyi Bridge. Furthermore, some processing measures like controlling time and temperature, continuous paving with two pavers, lateral feeding, and improving the compaction method were proposed. The project example shows that the processing measures can effectively solve the technical difficulties in the construction of orthotropic steel deck pavement of Haihe River Chunyi Bridge, can greatly improve the construction speed and quality, and can provide reference for the same kinds of orthotropic steel deck pavement construction.

  12. Experimental Investigation of Membrane Materials used in Multilayer Surfacing Systems for Orthotropic Steel Deck Bridges

    NARCIS (Netherlands)

    Tzimiris, G.

    2017-01-01

    In the Netherlands asphaltic surfacings on orthotropic steel deck bridges (OSDB) mostly consist of two structural layers. The upper layer consists of what is known as very open porous asphalt (ZOAB) for noise reduction. For the lower layer Guss Asphalt (GA) is used. Earlier investigations have shown

  13. FE-ANN based modeling of 3D Simple Reinforced Concrete Girders for Objective Structural Health Evaluation : Tech Transfer Summary

    Science.gov (United States)

    2017-06-01

    The objective of this study was to develop an objective, quantitative method for evaluating damage to bridge girders by using artificial neural networks (ANNs). This evaluation method, which is a supplement to visual inspection, requires only the res...

  14. FINITE ELEMENT ANALYSIS OF TAPERED COMPOSITE PLATE GIRDER WITH A NON-LINEAR VARYING WEB DEPTH

    Directory of Open Access Journals (Sweden)

    Q. A. HASAN

    2017-11-01

    Full Text Available The paper presents Finite Element Analysis to determine the ultimate shear capacity of tapered composite plate girder. The effect of degree of taper on the ultimate shear capacity of tapered steel-concrete composite plate girder with a nonlinear varying web depth, effect of slenderness ratio on the ultimate shear capacity, and effect of flange stiffness on the ductility were considered as the parametric studies. Effect of concrete slab on the ultimate shear capacity of tapered plate girders was also considered and it was found to be so effective on the ultimate shear capacity of the tapered plate girder compared with the steel one. The accuracy of the finite element method is established by comparing the finite element with the results existing in the literature. The study was conducted using nonlinear finite element modelling with computer software LUSAS 14.7.

  15. Problems of lamella flanges in steel bridge construction

    Czech Academy of Sciences Publication Activity Database

    Křístek, V.; Škaloud, Miroslav; Urushadze, Shota; Kunrt, J.

    2016-01-01

    Roč. 59, č. 1 (2016), s. 11-15 ISSN 2217-8139 R&D Projects: GA ČR(CZ) GA15-01035S Institutional support: RVO:68378297 Keywords : bridges * lamella flanges * repeated loading * breathing * limit states Subject RIV: JM - Building Engineering http://scindeks-clanci.ceon.rs/data/pdf/0543-0798/2016/0543-07981601011K.pdf

  16. Precast concrete elements for accelerated bridge construction : laboratory testing, field testing, evaluation of a precast concrete bridge, Madison County bridge.

    Science.gov (United States)

    2009-01-01

    The importance of rapid construction technologies has been recognized by the Federal Highway Administration (FHWA) and the Iowa : DOT Office of Bridges and Structures. Recognizing this a two-lane single-span precast box girder bridge was constructed ...

  17. Monitoring Bridge Dynamic Responses Using Fiber Bragg Grating Tiltmeters.

    Science.gov (United States)

    Xiao, Feng; Chen, Gang S; Hulsey, J Leroy

    2017-10-20

    In bridge health monitoring, tiltmeters have been used for measuring rotation and curvature; however, their application in dynamic parameter identification has been lacking. This study installed fiber Bragg grating (FBG) tiltmeters on the bearings of a bridge and monitored the dynamic rotational angle. The dynamic features, including natural frequencies and mode shapes, have been identified successfully. The innovation presented in this paper is the first-time use of FBG tiltmeter readings to identify the natural frequencies of a long-span steel girder bridge. The identified results have been verified using a bridge finite element model. This paper introduces a new method for the dynamic monitoring of a bridge using FBG tiltmeters. Limitations and future research directions are also discussed in the conclusion.

  18. Monitoring Bridge Dynamic Responses Using Fiber Bragg Grating Tiltmeters

    Directory of Open Access Journals (Sweden)

    Feng Xiao

    2017-10-01

    Full Text Available In bridge health monitoring, tiltmeters have been used for measuring rotation and curvature; however, their application in dynamic parameter identification has been lacking. This study installed fiber Bragg grating (FBG tiltmeters on the bearings of a bridge and monitored the dynamic rotational angle. The dynamic features, including natural frequencies and mode shapes, have been identified successfully. The innovation presented in this paper is the first-time use of FBG tiltmeter readings to identify the natural frequencies of a long-span steel girder bridge. The identified results have been verified using a bridge finite element model. This paper introduces a new method for the dynamic monitoring of a bridge using FBG tiltmeters. Limitations and future research directions are also discussed in the conclusion.

  19. Impact of measurement uncertainty from experimental load distribution factors on bridge load rating

    Science.gov (United States)

    Gangone, Michael V.; Whelan, Matthew J.

    2018-03-01

    Load rating and testing of highway bridges is important in determining the capacity of the structure. Experimental load rating utilizes strain transducers placed at critical locations of the superstructure to measure normal strains. These strains are then used in computing diagnostic performance measures (neutral axis of bending, load distribution factor) and ultimately a load rating. However, it has been shown that experimentally obtained strain measurements contain uncertainties associated with the accuracy and precision of the sensor and sensing system. These uncertainties propagate through to the diagnostic indicators that in turn transmit into the load rating calculation. This paper will analyze the effect that measurement uncertainties have on the experimental load rating results of a 3 span multi-girder/stringer steel and concrete bridge. The focus of this paper will be limited to the uncertainty associated with the experimental distribution factor estimate. For the testing discussed, strain readings were gathered at the midspan of each span of both exterior girders and the center girder. Test vehicles of known weight were positioned at specified locations on each span to generate maximum strain response for each of the five girders. The strain uncertainties were used in conjunction with a propagation formula developed by the authors to determine the standard uncertainty in the distribution factor estimates. This distribution factor uncertainty is then introduced into the load rating computation to determine the possible range of the load rating. The results show the importance of understanding measurement uncertainty in experimental load testing.

  20. Self-supporting method; an alternative method for steel truss bridge element replacement

    Science.gov (United States)

    Arsyad, Muhammad; Sangadji, Senot; As'ad, Sholihin

    2017-11-01

    Steel truss bridge often requires replacement of its element due to serious damage caused by traffic accidents. This replacement is carried out using temporary supporting structure. It would be difficult when the available space for the temporary structure is quite limited and or the position of work is at a high elevation. The self-supporting method is proposed instead of temporary supporting structure. This paper will discuss an innovative method of bridge rehabilitation by utilizing the existing bridge structure. It requires such temporary connecting structure that installed on the existing bridge element, therefore, the forces during replacement process could be transferred to the bridge foundation directly. By taking the case on a steel truss bridge Jetis Salatiga which requires element replacement due to its damages on two main diagonals, a modeling is carried out to get a proper repair method. Structural analysis is conducted for three temporary connecting structure models: “I,” “V,” and triangular model. Stresses and translations that occur in the structure are used as constraints. Bridge bearings are modeled in two different modes: fixed-fixed system and fixed-free one. Temperature load is given in each condition to obtain the appropriate time for execution. The triangular model is chosen as the best one. In the fixed-fixed mode, this method can be carried out in a temperature range 27-28.8° C, while in fixed-free one, the temperature it is allowed between 27-43.4 °C. The D4 is dismantled first by cutting the D4 leaving an area of 1140.2 mm2 or 127 mm web length to enable plastic condition until the D4 collapses. At the beginning of elongation occurs, immediately performed a slowly jacking on a temporary connecting structure so that the force on D4 is gradually transferred to the temporary connecting structure then the D4 and D5 are set in their place.

  1. A Damage Prognosis Method of Girder Structures Based on Wavelet Neural Networks

    Directory of Open Access Journals (Sweden)

    Rumian Zhong

    2014-01-01

    Full Text Available Based on the basic theory of wavelet neural networks and finite element model updating method, a basic framework of damage prognosis method is proposed in this paper. Firstly, a damaged I-steel beam model testing is used to verify the feasibility and effectiveness of the proposed damage prognosis method. The results show that the predicted results of the damage prognosis method and the measured results are very well consistent, and the maximum error is less than 5%. Furthermore, Xinyihe Bridge in the Beijing-Shanghai Highway is selected as the engineering background, and the damage prognosis is conducted based on the data from the structural health monitoring system. The results show that the traffic volume will increase and seasonal differences will decrease in the next year and a half. The displacement has a slight increase and seasonal characters in the critical section of mid span, but the strain will increase distinctly. The analysis results indicate that the proposed method can be applied to the damage prognosis of girder bridge structures and has the potential for the bridge health monitoring and safety prognosis.

  2. Flexible concrete link slabs used as expansion joints in bridge decks

    DEFF Research Database (Denmark)

    Lárusson, Lárus Helgi; Fischer, Gregor

    2011-01-01

    of water through the expansion joint and subsequent corrosion of girders and girder bearings. Investigations on joint-less superstructures using conventional steel reinforcement in so-called concrete link slabs indicate improved performance and economic feasibility. However, this concept requires...... relatively large amounts of steel reinforcement for crack control purposes and consequently provides a relatively large flexural stiffness and negative moment capacity at the joint between the spans. These contradicting requirements and effects in existing replacement concepts for damaged mechanical bridge...... joints are currently unresolved. In the proposed system described in this paper, a ductile cement-based composite section reinforced with Glass Fiber Reinforced Polymers (GFRP) replaces the damaged expansion joint. The combination of this ductile concrete together with corrosion resistant GFRP...

  3. Dynamic and Fatigue Analysis of an 18th Century Steel Arch Bridge

    International Nuclear Information System (INIS)

    Boumechra, Nadir; Hamdaoui, Karim

    2008-01-01

    Within the 'Oran-Tlemcen' railway line realization project (159 km), several bridges were built by the Railroads Algerian West Company. 7 km from the east of Tlemcen city, this railway line must cross a very broken mountainous collar, that's why the French engineer 'Gustave Eiffel' was solicited to construct a 68 m length bridge. In 1890, an arch steel truss bridge was realized. The bridge presents 300 m of apron curvature radius and, currently, is considered as one of the most important monuments of the Algerian historical heritage. Considering the age of the bridge and the evolution of the railway loads in time, it was essential to check the good behavior of the studied structure. For that, analyses to verify the physical and mechanical properties of the growth iron members are made. A finite element model of the bridge was built and numerical simulations were drawn. The structural vibration conducted analysis permit to understand the behavior of this particular structure, then to evaluate (in detail) the rate of the structure fatigue

  4. Multi-parameters sensitivity analysis of natural vibration modal for steel arch bridge

    Directory of Open Access Journals (Sweden)

    WANG Ying

    2014-02-01

    Full Text Available Because of the vehicle loads and environmental factors,the behaviors of bridge structure in service is becoming deterioration.The modal parameters are important indexes of structure,so sensitivity analysis of natural vibration is an important way to evaluate the behavior of bridge structure.In this paper,using the finite element software Ansys,calculation model of a steel arch bridge was built,and the natural vibration modals were obtained.In order to compare the different sensitivity of material parameters which may affect the natural vibration modal,5 factors were chosen to perform the calculation.The results indicated that different 5 factors had different sensitivity.The leading factor was elastic modulus of arch rib,and the elastic modulus of suspender had little effect to the sensitivity.Another argument was the opposite sensitivity effect happened between the elastic modulus and density of the material.

  5. Nondestructive Evaluation of Railway Bridge by System Identification Using Field Vibration Measurement

    International Nuclear Information System (INIS)

    Ho, Duc Duy; Hong, Dong Soo; Kim, Jeong Tae

    2010-01-01

    This paper presents a nondestructive evaluation approach for system identification (SID) of real railway bridges using field vibration test results. First, a multi-phase SID scheme designed on the basis of eigenvalue sensitivity concept is presented. Next, the proposed multi-phase approach is evaluated from field vibration tests on a real railway bridge (Wondongcheon bridge) located in Yangsan, Korea. On the steel girder bridge, a few natural frequencies and mode shapes are experimentally measured under the ambient vibration condition. The corresponding modal parameters are numerically calculated from a three-dimensional finite element (FE) model established for the target bridge. Eigenvalue sensitivities are analyzed for potential model-updating parameters of the FE model. Then, structural subsystems are identified phase-by-phase using the proposed model-updating procedure. Based on model-updating results, a baseline model and a nondestructive evaluation of test bridge are identified

  6. Wind Turbine Blade with Angled Girders

    DEFF Research Database (Denmark)

    2011-01-01

    The present invention relates to a reinforced blade for a wind turbine, particularly to a blade having a new arrangement of two or more girders in the blade, wherein each of the girders is connected to the upper part and the lower part of the shell and forms an angle with another girder thereby...

  7. Research on Collapse Process of Cable-Stayed Bridges under Strong Seismic Excitations

    Directory of Open Access Journals (Sweden)

    Xuewei Wang

    2017-01-01

    Full Text Available In order to present the collapse process and failure mechanism of long-span cable-stayed bridges under strong seismic excitations, a rail-cum-road steel truss cable-stayed bridge was selected as engineering background, the collapse failure numerical model of the cable-stayed bridge was established based on the explicit dynamic finite element method (FEM, and the whole collapse process of the cable-stayed bridge was analyzed and studied with three different seismic waves acted in the horizontal longitudinal direction, respectively. It can be found from the numerical simulation analysis that the whole collapse failure process and failure modes of the cable-stayed bridge under three different seismic waves are similar. Furthermore, the piers and the main pylons are critical components contributing to the collapse of the cable-stayed bridge structure. However, the cables and the main girder are damaged owing to the failure of piers and main pylons during the whole structure collapse process, so the failure of cable and main girder components is not the main reason for the collapse of cable-stayed bridge. The analysis results can provide theoretical basis for collapse resistance design and the determination of critical damage components of long-span highway and railway cable-stayed bridges in the research of seismic vulnerability analysis.

  8. Fatigue analysis and life prediction of composite highway bridge decks under traffic loading

    Directory of Open Access Journals (Sweden)

    Fernando N. Leitão

    Full Text Available Steel and composite (steel-concrete highway bridges are currently subjected to dynamic actions of variable magnitude due to convoy of vehicles crossing on the deck pavement. These dynamic actions can generate the nucleation of fractures or even their propagation on the bridge deck structure. Proper consideration of all of the aspects mentioned pointed our team to develop an analysis methodology with emphasis to evaluate the stresses through a dynamic analysis of highway bridge decks including the action of vehicles. The design codes recommend the application of the curves S-N associated to the Miner's damage rule to evaluate the fatigue and service life of steel and composite (steel-concrete bridges. In this work, the developed computational model adopted the usual mesh refinement techniques present in finite element method simulations implemented in the ANSYS program. The investigated highway bridge is constituted by four longitudinal composite girders and a concrete deck, spanning 40.0m by 13.5m. The analysis methodology and procedures presented in the design codes were applied to evaluate the fatigue of the bridge determining the service life of the structure. The main conclusions of this investigation focused on alerting structural engineers to the possible distortions, associated to the steel and composite bridge's service life when subjected to vehicle's dynamic actions.

  9. Fatigue assessment for selected connections of structural steel bridge components using the finite elements method

    Science.gov (United States)

    Śledziewski, Krzysztof

    2018-01-01

    Material fatigue it is one of the most frequent causes of steel bridge failures, particularly the bridges already existing. Thus, the procedure of fatigue life assessment is one of the most relevant procedures in a comprehensive assessment of load-carrying capacity and service life of the structure. A reliable assessment of the fatigue life is predominantly decisive for estimation of the remaining service life. Hitherto, calculation methods of welded joints took into account only stresses occurring in cross sections of whole elements and did not take into account stress concentration occurring in the vicinity of the weld, caused by geometrical aspects of the detail. At present, use of the Finite Element Analysis, makes possible looking for more accurate approach to the fatigue design of steel structures. The method of geometrical stresses is just such approach which is based on definition of stresses which take into account geometry of the detail. The study presents fatigue assessment of a representative type of welded joint in welded bridge structures. The testing covered longitudinal attachments. The main analyses were carried out on the basis of FEM and the method of local stresses, so-called "hot-spot" stresses. The obtained values of stresses were compared with the values obtained in accordance with the method of nominal stress.

  10. Experimental Investigation for Behavior of Spliced Continuous RC Girders Strengthened with CFRP Laminates

    Directory of Open Access Journals (Sweden)

    Ammar Yasir Ali

    2016-03-01

    Full Text Available In this paper, the behavior of spliced continuous reinforced concrete girders was experimentally investigated. The main objective was to examine the contribution of the carbon fiber reinforced polymer (CFRP laminates in strengthening the spliced continuous reinforced concrete girders. Eight models of continuous reinforced concrete girder were constructed and tested. The test variables were strengthening the splice joints by different schemes of CFRP laminates, presence of horizontal stirrups through the interfaces of the joints and using binder material at the interfaces of the joints. The results showed that strengthening the continuous spliced girders with 45° inclined CFRP laminates led to an increase in the ultimate load in a range of (47 to 74%. Besides, strengthening the continuous spliced girder with horizontal CFRP laminates bonded at its lateral faces could increase the ultimate load by 70%. Additionally, the ultimate load of the continuous spliced girder was increased by (30% due to presence of the horizontal steel stirrups through the interfaces of the joints

  11. Design of pedestrian truss bridge with Sengon-Rubber laminated veneer lumber

    Science.gov (United States)

    Herbudiman, B.; Pranata, Y. A.; Pangestu, L.

    2017-12-01

    Timber bridges are one of the bridge that has long been used, but nowadays, large dimension of sawn timber has limited supply and also it is not environmental-friendly. Laminated veneer lumber (LVL) is a engineered wood that becomes one of the promising alternative, because it is made from lower quality wood that processed to be used as a more quality one. The bridge planned to be a pedestrian truss bridge with length of 9 m, width of 3 m, height of 2.5 m, and using bolt and steel plate as its connection system. Mechanical properties of LVL obtained directly from laboratory test result. Bridge modeling and planning for wood construction refers to SNI 7973:2013, while the loading refers to SNI 1725:2016. Based on the modelling and calculation, the dimension of truss frame and girder beam which are 9 cm x 9 cm and 9 cm x 18 cm have adequate strengths and satisfy deflection requirement.

  12. Assessing the need for intermediate diaphragms in prestressed concrete bridges.

    Science.gov (United States)

    2008-03-01

    Reinforced concrete intermediate diaphragms (IDs) are currently being used in prestressed concrete (PC) girder bridges in Louisiana. Some of the advantages of providing IDs are disputed in the bridge community; the use of IDs increases the cost and t...

  13. Suppression of deicing salt corrosion of weathering steel bridges by washing

    International Nuclear Information System (INIS)

    Hara, Shuichi; Miura, Masazumi; Uchiumi, Yasushi; Fujiwara, Toshiaki; Yamamoto, Masataka

    2005-01-01

    To elucidate the influences of deicing salts and high pressure (2-4 MPa) washing on the characteristics of the rust formed on weathering steel bridges, washing experiments have been carried out for three years. The rust was characterized by means of ion chromatography, X-ray diffraction and adsorption of N 2 . The rust thickness was measured, and also the rust weight per unit area of the steel surface was measured. It was found that water-soluble chloride accelerated the rate of corrosion because the rust particles grow by the chloride ions and micro-pore structure of the rust appeared by the chloride ions. Washing with water suppressed corrosion owing to the disappearance of chloride ions

  14. Design and construction of Chichibu-park bridge. Chichibu Koenkyo (kasho) no sekkei to seko

    Energy Technology Data Exchange (ETDEWEB)

    Hasuike, H.; Azami, Y. (Saitama Prefectural Government Office, Saitama (Japan) New Structural Engineering, Ltd., Tokyo (Japan)); Yamamoto, T.

    1994-01-31

    The design and construction of the Chichibu-Park Bridge in Japan were outlined which is the symmetric 2-span continuous PC cable stayed road bridge with one main tower (530 m in total length, 392 m in main bridge length, 19 m in width) built over the Arakawa River. The double-suspended four-box main girder with wind noses was adopted because of its excellent torsional rigidity of area and wind proof stability, and the rigid-frame main girder was rigidly connected to the middle main tower. The main tower with an H-type hollow section was adopted considering its workability, and was assembled with its divided 18 blocks. Each side of the main girder was suspended at 30 points spaced at 6.0 m, and the tower ends of the diagonal cables were fixed to the partition inside the main tower taking a landscape into account. The thick stranded wires composed of fine PC steel stranded wires and covered with polyethylene were adopted as diagonal cables, and structural beams were used for both ends of the diagonal cables. Damping wires were also adopted to damp the diagonal cables. 9 refs., 12 figs., 6 tabs.

  15. Design and test of a girder control system at NSRRC

    International Nuclear Information System (INIS)

    Wang, H.S.; Tsai, Y.L.; Perng, S.Y.; Chen, M.L.; Hsu, K.H.; Lai, W.Y.; Tseng, T.C.; Chen, J.R.

    2012-01-01

    A girder control system is proposed to quickly and precisely adjust the displacement and rotating angle of all girders in the storage ring with little manpower at the Taiwan Photon Source (TPS) project at National Synchrotron Research Center (NSRRC). In this control girder system, six motorized cam movers supporting a girder are driven on three pedestals to perform six-axis adjustments of a girder. A tilt-meter monitors the pitch and roll of each girder; several touch sensors measure the relative displacement between consecutive girders. Moreover, a laser position sensitive detector (PSD) system measuring the relative displacement between straight-section girders is included in this girder control system. Operator can use subroutines developed by MATLAB to control every local girder control system via the web. The test results show that the girder control system adjusts girders quickly, precisely and stably

  16. Performance of self-consolidating concrete in prestressed girders.

    Science.gov (United States)

    2010-04-01

    A structural investigation of self-consolidating concrete (SCC) in AASHTO Type I precast, : prestressed girders was performed. Six test girders were subjected to transfer length and : flexural testing. Three separate concrete mixtures, two girders pe...

  17. Bridge Management Systems

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper bridge management systems are discussed with special emphasis on management systems for reinforced concrete bridges. Management systems for prestressed concrete bridges, steel bridges, or composite bridges can be developed in a similar way....

  18. Assessment of exposure pathways connected with construction and operation of concrete bridge reinforced with very low level radioactive steel

    International Nuclear Information System (INIS)

    Panik, M.; Necas, V.

    2012-01-01

    Large amount of low level radioactive material arises during decommissioning of nuclear power plants. Material mostly comprises metal scrap and concrete ruble. Paper deals with recycling and reuse of metal scrap and its utilization as part of reinforcement of concrete bridges under the conditional release concept. Radiation exposure originating in very low level reinforcement steel consists of several exposure pathways. Short-term radiation impact is represented mostly by external exposure pathway and it is relevant to the construction workers and users of the bridge. Long-term radiation impacts on inhabitants living near finished bridge and it is divided into inhalation and ingestion of radionuclides-internal exposure pathways. Radiation impact caused by utilization of very low level radioactive waste was calculated using simulation software VISIPLAN 3D ALARA and GOLDSIM. Results of calculations provide fair summary of possibilities of utilization of conditionally released steel as reinforcement of concrete bridges. (Authors)

  19. Numerical simulations and experimental measurements of steel and ice impacts on concrete for acoustic interrogation of delaminations in bridge decks

    Energy Technology Data Exchange (ETDEWEB)

    Mazzeo, Brian A.; Patil, Anjali N.; Klis, Jeffrey M. [Brigham Young University, Department of Electrical and Computer Engineering, Provo, Utah, 84602 (United States); Hurd, Randy C.; Truscott, Tadd T. [Brigham Young University, Department of Mechanical Engineering, Provo, Utah, 84602 (United States); Guthrie, W. Spencer [Brigham Young University, Department of Civil and Environmental Engineering, Provo, Utah, 84602 (United States)

    2014-02-18

    Delaminations in bridge decks typically result from corrosion of the top mat of reinforcing steel, which leads to a localized separation of the concrete cover from the underlying concrete. Because delaminations cannot be detected using visual inspection, rapid, large-area interrogation methods are desired to characterize bridge decks without disruption to traffic, without the subjectivity inherent in existing methods, and with increased inspector safety. To this end, disposable impactors such as water droplets or ice chips can be dropped using automatic dispensers onto concrete surfaces to excite mechanical vibrations while acoustic responses can be recorded using air-coupled microphones. In this work, numerical simulations are used to characterize the flexural response of a model concrete bridge deck subject to both steel and ice impactors, and the results are compared with similar experiments performed in the laboratory on a partially delaminated concrete bridge deck slab. The simulations offer greater understanding of the kinetics of impacts and the responses of materials.

  20. Numerical Simulation of Hysteretic Live Load Effect in a Soil-Steel Bridge

    Directory of Open Access Journals (Sweden)

    Sobótka Maciej

    2014-03-01

    Full Text Available The paper presents numerical simulation of hysteretic live load effect in a soil-steel bridge. The effect was originally identified experimentally by Machelski [1], [2]. The truck was crossing the bridge one way and the other in the full-scale test performed. At the same time, displacements and stress in the shell were measured. The major conclusion from the research was that the measured quantities formed hysteretic loops. A numerical simulation of that effect is addressed in the present work. The analysis was performed using Flac finite difference code. The methodology of solving the mechanical problems implemented in Flac enables us to solve the problem concerning a sequence of load and non-linear mechanical behaviour of the structure. The numerical model incorporates linear elastic constitutive relations for the soil backfill, for the steel shell and the sheet piles, being a flexible substructure for the shell. Contact zone between the shell and the soil backfill is assumed to reflect elastic-plastic constitutive model. Maximum shear stress in contact zone is limited by the Coulomb condition. The plastic flow rule is described by dilation angle ψ = 0. The obtained results of numerical analysis are in fair agreement with the experimental evidence. The primary finding from the performed simulation is that the slip in the interface can be considered an explanation of the hysteresis occurrence in the charts of displacement and stress in the shell.

  1. Optimization of the box-girder of overhead crane with constrained ...

    African Journals Online (AJOL)

    Keywords: Overhead crane - Box-girder - New bat algorithm - level of comparison - Higher strength steel. Optimisation de poutre caisson de pont roulant avec un nouvel algorithme de chauve souris sous contrainte. Une conception optimale pour un poids minimal de la poutre principale d'un pont roulant peut réduire ...

  2. Evaluation of stresses generated in steel finger joint of bridge by X-ray stress measurement

    International Nuclear Information System (INIS)

    Kohri, Ami; Kawano, Yutaka; Nishido, Takayuki

    2017-01-01

    In a steel bridge, the evaluation of the stress generated in the finger joint without a gap to absorb temperature change can be an index when evaluating the remaining life. This study chose as the object the finger joint of a diagonal bridge, where the generated stress state is considered to be more complicated, prepared a finger joint test specimen that simulated an actual part, and performed a load test. For judgment, FEM analysis, non-destructive X-ray stress measurement, and measurement of the generated stress using strain gauge were applied. Compared with the FEM analysis results, the difference in the stress value was generated due to the difference in the contact state, but the trends of the stress distribution were equivalent. In addition, the same measurement value as the strain gauge was obtained, and the validity of the X-ray stress measurement method was confirmed. As a result, it was found that the stress measurement method by X-ray is effective for measuring the generated stress including the residual stress of the finger joint without gap at a bridge. (A.O.)

  3. Arch-Axis Coefficient Optimization of Long-Span Deck-Type Concrete-Filled Steel Tubular Arch Bridge

    Science.gov (United States)

    Liu, Q. J.; Wan, S.; Liu, H. C.

    2017-11-01

    This paper is based on Nanpuxi super major bridge which is under construction and starts from Wencheng Zhejiang province to Taishun highway. A finite element model of the whole bridge is constructed using Midas Civil finite element software. The most adverse load combination in the specification is taken into consideration to determine the method of calculating the arch-axis coefficient of long-span deck-type concrete-filled steel tubular arch bridge. By doing this, this paper aims at providing references for similar engineering projects.

  4. Christian Menn's recent bridge designs - Reducing structural elements to the simplest solution

    OpenAIRE

    Brühwiler, E.; Mahmoud, Khaled M.

    2009-01-01

    The conceptual designs by Christian Menn of four landmark bridges are presented: 1) a 350-m span cable-stayed bridge with jointless deck girder, 2) a cable-stayed bridge with a single “spindle-shaped” pylon, 3) a bridge with an arch reaching high above the deck (both carrying a horizontally curved deck girder), and 4) a cable stayed bridge with three pylons monolithically connected to the deck girder. All of the original bridge designs are driven by the aim to optimize the flow of force...

  5. Fuzzy stochastic analysis of serviceability and ultimate limit states of two-span pedestrian steel bridge

    Science.gov (United States)

    Kala, Zdeněk; Sandovič, GiedrÄ--

    2012-09-01

    The paper deals with non-linear analysis of ultimate and serviceability limit states of two-span pedestrian steel bridge. The effects of random material and geometrical characteristics on limit states are analyzed. The Monte Carlo method was applied to stochastic analysis. For the serviceability limit state, also influence of fuzzy uncertainty of the limit deflection value on random characteristics of load capacity of variable action was studied. The results prove that, for the type of structure studied, the serviceability limit state is decisive from the point of view of design. The present paper opens a discussion on the use of stochastic analysis to verify the limit deflections given in the standards EUROCODES.

  6. Behaviour of Steel Fibre Reinforced Rubberized Continuous Deep Beams

    Science.gov (United States)

    Sandeep, MS; Nagarajan, Praveen; Shashikala, A. P.

    2018-03-01

    Transfer girders and pier caps, which are in fact deep beams, are critical structural elements present in high-rise buildings and bridges respectively. During an earthquake, failure of lifeline structures like bridges and critical structural members like transfer girders will result in severe catastrophes. Ductility is the key factor that influences the resistance of any structural member against seismic action. Structural members cast using materials having higher ductility will possess higher seismic resistance. Previous research shows that concrete having rubber particles (rubcrete) possess better ductility and low density in comparison to ordinary concrete. The main hindrance to the use of rubcrete is the reduction in compressive and tensile strength of concrete due to the presence of rubber. If these undesirable properties of rubcrete can be controlled, a new cementitious composite with better ductility, seismic performance and economy can be developed. A combination of rubber particles and steel fibre has the potential to reduce the undesirable effect of rubcrete. In this paper, the effect of rubber particles and steel fibre in the behaviour of two-span continuous deep beams is studied experimentally. Based on the results, optimum proportions of steel fibre and rubber particles for getting good ductile behaviour with less reduction in collapse load is found out.

  7. Lateral dynamic interaction analysis of a train girder pier system

    Science.gov (United States)

    Xia, H.; Guo, W. W.; Wu, X.; Pi, Y. L.; Bradford, M. A.

    2008-12-01

    A dynamic model of a coupled train-girder-pier system is developed in this paper. Each vehicle in a train is modeled with 27 degrees-of-freedom for a 4-axle passenger coach or freight car, and 31 for a 6-axle locomotive. The bridge model is applicable to straight and curved bridges. The centrifugal forces of moving vehicles on curved bridges are considered in both the vehicle model and the bridge model. The dynamic interaction between the bridge and train is realized through an assumed wheel-hunting movement. A case study is performed for a test train traversing two straight and two curved multi-span bridges with high piers. The histories of the train traversing the bridges are simulated and the dynamic responses of the piers and the train vehicles are calculated. A field experiment is carried out to verify the results of the analysis, by which the lateral resonant train speed inducing the peak pier-top amplitudes and some other observations are validated.

  8. AE characteristic for monitoring of fatigue crack in steel bridge members

    Science.gov (United States)

    Yoon, Dong-Jin; Jung, Juong-Chae; Park, Philip; Lee, Seung-Seok

    2000-06-01

    Acoustic emission technique was employed for the monitoring of crack activity in both steel bridge members and laboratory specimen. Laboratory experiment was carried out to identify AE characteristics of fatigue cracks for compact tension specimen. The relationship between a stress intensity factor and AE signals activity as well as conventional AE parameter analysis was discussed. A field test was also conducted on a railway bridge, which contain several fatigue cracks. Crack activities were investigated while in service with strain measurement. From the results, in the laboratory tests, the features of three parameters such as the length of crack growth, the AE energy, and the cumulative AE events, showed the almost same trend in their increase as the number of fatigue cycle increased. From the comparisons of peak amplitude and AE energy with stress intensity factor, it was verified that the higher stress intensity factors generated AE signals with higher peak amplitude and a large number of AE counts. In the field test, real crack propagation signals were captured and the crack activity was verified in two cases.

  9. Influence of molybdenum content on transformation behavior of high performance bridge steel during continuous cooling

    International Nuclear Information System (INIS)

    Chen, Jun; Tang, Shuai; Liu, Zhenyu; Wang, Guodong

    2013-01-01

    Highlights: ► The bainite transformation field was refined. ► The empirical equation to estimate the GF s was established. ► Transformation behavior was studied with serially increasing Mo addition. ► The molybdenum content can be lowered as the cooling rate is increased. ► GF transformation field is also shifted to right by increasing Mo content. - Abstract: The continuous-cooling-transformation (CCT) diagrams of high performance bridge steel with different molybdenum content were plotted by means of a combined method of dilatometry and metallography. The results show that the molybdenum addition of 0.17 wt% does not noticeably alter the transformation behavior, whereas 0.38 wt% significantly. In addition, the molybdenum addition of 0.38 wt% completely eliminates the formation of polygonal ferrite (PF) and significantly lower the granular ferrite (GF) transformation starting temperatures throughout the range of cooling rates studied. At lower cooling rates, with the increase of the molybdenum content, the martensite/austenite (M/A) constituents are noticeably refined, whereas the effects are not obvious at higher cooling rates. Moreover, the molybdenum addition of 0.38 wt% can significantly increase the Vickers hardness, but the Vickers hardness increments (by comparison of Mo-0.17wt% steel and Mo-0.38wt% steel) are sharply reduced at the cooling rate of 30 °C/s, indicating that at higher cooling rate, the molybdenum usage can be saved and the higher strengthen can be also gained. It could be found the GF transformation starting temperature is linear with the cooling rate. The empirical equation was established to calculate GF transformation starting temperatures, and the calculated values are in good agreement with measured ones

  10. Evaluation of external exposure during building and operation of concrete bridges constructions that reuse the conditionally released steels - 59120

    International Nuclear Information System (INIS)

    Panik, Michal; Necas, Vladimir

    2012-01-01

    This paper presents ongoing results of the project presented at ICEM'10 [1] related to the topics of reusing the conditionally released materials from decommissioning. The subject of the reuse of conditionally released materials in this case is modeling of bridge constructions which reuse the conditionally released steel in the form of reinforcement bars for the concrete bridges. A general approach for the project was presented at ICEM'10. The activities of the project continue in evaluating the individual effective doses from the external exposure based on reused conditionally released steels separately for public and for professionals (the internal exposure will be evaluated in next stages of the project). Evaluated scenarios are related to critical groups of professionals constructing the bridges (worker's scenarios). The computer code VISIPLAN 3D ALARA 4.0 planning tool was used for the calculation of the individual effective dose for professionals. Various limits of the annual individual effective dose are used for the evaluation of calculation results. The aim of the ongoing modeling is to develop a set of data of maximal radioactivity concentration for individual radionuclides in the conditionally released steel used in the bridges model constructions in order not to exceed the limits for the individual effective dose. (authors)

  11. Bridges

    NARCIS (Netherlands)

    Zant, W.

    2017-01-01

    We estimate to what extent bridges in Mozambique lead to transport cost reductions and attribute these reductions to key determinants, in particular road distance, road quality and crossing borders. For identification we exploit the introduction of a road bridge over the Zambezi river, in August

  12. Effect of Ni on the corrosion resistance of bridge steel in a simulated hot and humid coastal-industrial atmosphere

    Science.gov (United States)

    Li, Dong-liang; Fu, Gui-qin; Zhu, Miao-yong; Li, Qing; Yin, Cheng-xiang

    2018-03-01

    The corrosion resistance of weathering bridge steels containing conventional contents of Ni (0.20wt%, 0.42wt%, 1.50wt%) and a higher content of Ni (3.55wt%) in a simulated hot and humid coastal-industrial atmosphere was investigated by corrosion depth loss, scanning electron microscopy-energy-dispersive X-ray spectroscopy, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and electrochemical methods. The results showed that, with increasing Ni content, the mechanical properties of the bridge steel were markedly improved, the welding parameters were satisfactory at room temperature, and the corrosion resistance was enhanced. When the Ni content was low (≤0.42wt%), the crystallization process of the corrosion products was substantially promoted, enhancing the stability of the rust layer. When the Ni content was higher ( 3.55wt%), the corrosion reaction of the steel quickly reached a balance, because the initial rapid corrosion induced the formation of a protective rust layer in the early stage. Simultaneously, NiO and NiFe2O2 were generated in large quantities; they not only formed a stable, compact, and continuous oxide protective layer, but also strongly inhibited the transformation process of the corrosion products. This inhibition reduced the structural changes in the rust layer, thereby enhancing the protection. However, when the Ni content ranged from 0.42wt% to 1.50wt%, the corrosion resistance of the bridge steel increased only slightly.

  13. Experimental testing of post-tensioned concrete girders instrumented with optical fibre gratings

    Science.gov (United States)

    Matthys, S.; Taerwe, L.

    2005-05-01

    The integration of optical fibre strain sensors in concrete structures in order to measure deformations has proven to be successful in several applications. Examples of monitored structures by the Magnel Laboratory for Concrete Research are a concrete girder bridge over the Ring Canal by Ghent, a Quay wall at the Ring Canal and a trough girder containing a railway track of a bridge [1,2]. Based on a joint research project the feasibility of integrating Bragg grating sensors in concrete in order to statically and dynamically monitor 17.6 m long prestressed concrete girders has been investigated. During the project 3 post-tensioned concrete girders were tested, submitting them to static and dynamic loading conditions and monitoring the structural behavior with several types of measuring devices, including accelerometers, Bragg gratings, Fabry-Perot gratings, deformeters, crack microscopes, etc. The obtained test results demonstrate the feasibility of optical strain sensors for both static and dynamic measurements. Though it was demonstrated, in the case of dynamic monitoring, that optical strain measurements can be used to directly measure the modal strains, the project also demonstrated that for prestressed concrete the variation in dynamic parameters was insufficient for adequate dynamic monitoring and related damage diagnostics.

  14. Deflection monitoring for a box girder based on a modified conjugate beam method

    Science.gov (United States)

    Chen, Shi-Zhi; Wu, Gang; Xing, Tuo

    2017-08-01

    After several years of operation, a box girder bridge would commonly experience excessive deflection, which endangers the bridge’s life span as well as the safety of vehicles travelling on it. In order to avoid potential risks, it is essential to constantly monitor the defection of box girders. However, currently, the direct deflection monitoring methods are limited by the complicated environments beneath the bridges, such as rivers or other traffic lanes, which severely impede the layouts of the sensors. The other indirect deflection monitoring methods mostly do not thoroughly consider the inherent shear lag effect and shear deformation in the box girder, resulting in a rather large error. Under these circumstances, a deflection monitoring method suiting box girders is proposed in this article, based on the conjugate beam method and distributed long-gauge fibre Bragg grating (FBG) sensor. A lab experiment was conducted to verify the reliability and feasibility of this method under practical application. Further, the serviceability under different span-depth ratios and web thicknesses was examined through a finite element model.

  15. Nonlinear seismic analysis of continuous RC bridge

    Directory of Open Access Journals (Sweden)

    Čokić Miloš M.

    2017-01-01

    Full Text Available Nonlinear static analysis, known as a pushover method (NSPA is oftenly used to study the behaviour of a bridge structure under the seismic action. It is shown that the Equivalent Linearization Method - ELM, recommended in FEMA 440, is appropriate for the response analysis of the bridge columns, with different geometric characteristics, quantity and distribution of steel reinforcement. The subject of analysis is a bridge structure with a carriageway plate - a continuous beam with three spans, with the 24 + 40 + 24 m range. Main girder is made of prestressed concrete and it has a box cross section of a constant height. It is important to study the behaviour, not only in the transverse, but also in the longitudinal direction of the bridge axis, when analysing the bridge columns exposed to horizontal seismic actions. The columns were designed according to EN1992, parts 1 and 2. Seismic action analysis is conducted according to EN 1998: 2004 standard. Response spectrum type 1, for the ground type B, was applied and the analysis also includes 20% of traffic load. The analysis includes the values of columns displacement and ductility. To describe the behaviour of elements under the earthquake action in both - longitudinal and transverse direction, pushover curves were formed.

  16. Hybrid knowledge expert tool for load capacity assessment of railway plate girders with defects

    Science.gov (United States)

    KuŻawa, M.; Bień, J.; Gładysz, M.

    2013-10-01

    Importance of the bridge structures as components of the transportation network is increasing and requires regular development of the management methodology. The main activities are focused on the safety of the users of the transportation network and on the safety of structures, based on monitoring and analysis of the bridge condition changes caused by various types of defects. The paper presents application of the hybrid network technology in the expert tool NOBLA supporting condition assessment of bridge plate girders, taking into account defects of the structures.

  17. Geodetic monitoring (TLS of a steel transport trestle bridge located in an active mining exploitation site

    Directory of Open Access Journals (Sweden)

    Skoczylas Arkadiusz

    2016-09-01

    Full Text Available Underground mining exploitation causes, in general, irregular vertical and horizontal shifts in the superficial layer of the rock mass. In the case of construction objects seated on this layer, a deformation of the object’s foundation can be observed. This leads to additional loads and deformations. Identification of surface geometry changes in construction objects located within the premises of underground mining exploitation areas is an important task as far as safety of mining sites is concerned. Surveys targeting shifts and deformations in engineering objects preformed with the use of classic methods are of a selective nature and do not provide the full image of the phenomenon being the subject of the observation. This paper presents possibilities of terrestrial laser scanning technology application in the monitoring of engineering objects that allows for a complete spatial documentation of an object subjected to the influence of an active mining exploitation. This paper describes an observation of a 100 m section of a steel transport trestle bridge located on the premises of hard coal mine Lubelski Węgiel “Bogdanka” S.A. carried out in 2015. Measurements were carried out using a Z+F Imager 5010C scanner at an interval of 3.5 months. Changes in the structure’s geometry were determined by comparing the point clouds recorded during the two measurement periods. The results of the analyses showed shifts in the trestle bridge towards the exploited coal wall accompanied by object deformation. The obtained results indicate the possibility of of terrestrial laser scanning application in studying the aftereffects of underground mining exploitation on surface engineering objects.

  18. X-ray diffraction analysis of rust layer on a weathering steel bridge with surface treatment using synchrotron radiation

    International Nuclear Information System (INIS)

    Yamashita, Masato; Hara, Shuichi; Kamimura, Takayuki; Miyuki, Hideaki; Sato, Masugu

    2007-01-01

    We have examined the structure of rust layer formed on a weathering steel bridge, to which the surface treatment, employing the effect of Cr 2 (SO 4 ) 3 sophisticatedly designed to form the protective goethite (α-FeOOH) rust layer which contains a certain amount of Cr, Cr-goethite, was applied in 1996, using X-ray diffraction at SPring-8 synchrotron radiation facility. It was shown that the formation of α-FeOOH was promoted and/or crystal growth of γ-FeOOH was suppressed by the surface treatment. The increase in the protective ability index (PAI) of the rust layer indicates that the protective goethite was predominantly formed under the effect of the surface treatment. In conclusion, it can be said that the surface treatment worked well to promote the formation of the protective goethite rust layer on the weathering steel bridge during the 10-year exposure. (author)

  19. Optimum design of large span concrete filled steel tubular arch bridge based on static, stability and modal analysis

    Institute of Scientific and Technical Information of China (English)

    赵长军; 胡隽; 徐兴

    2002-01-01

    A three-dimensional finite element model was established for a large span concrete filled steel tubular (CFST) arch bridge which is currently under construction. The arch rib, the spandrel columns, the prestressed concrete box-beam, the cast-in-situ concrete plate of bridge deck, the steel box-beam and the crossbeams connecting the two pieces of arch ribs, were modeled by three-dimensional Timoshenko beam elements (3DTBE). The suspenders were modeled by three-dimensional cable elements (3DCE). Both geometric nonlinearity and prestress effect could be included in each kind of element. At the same time a second finite element model with the same geometric and material properties excepted for the sectional dimension of arch rib was set up. Static dynamic analyses were performed to determine the corresponding characteristics of the structure. The results showed that the arch rib's axial rigidity could be determined by static analysis. The stability and vibration of this system could be separated into in-plane modes, out-of-plane modes and coupled modes. The in-plane stability and dynamic characteristics are determined by the arch rib's vertical stiffness and that of out-of-plane is determined by the crossbeams' stiffness and arch rib's lateral stiffness mainly. The in-plane stiffness is much greater than that of out-of-plane for this kind of bridge . The effect of geometric nonlinearity and prestress effect on bridge behavior is insignificant.

  20. APPLICATION OF STEEL PIPE PILE LOADING TESTS TO DESIGN VERIFICATION OF FOUNDATION OF THE TOKYO GATE BRIDGE

    Science.gov (United States)

    Saitou, Yutaka; Kikuchi, Yoshiaki; Kusakabe, Osamu; Kiyomiya, Osamu; Yoneyama, Haruo; Kawakami, Taiji

    Steel sheet pipe pile foundations with large diameter steel pipe sheet pile were used for the foundation of the main pier of the Tokyo Gateway bridge. However, as for the large diameter steel pipe pile, the bearing mechanism including a pile tip plugging effect is still unclear due to lack of the practical examinations even though loading tests are performed on Trans-Tokyo Bay Highway. In the light of the foregoing problems, static pile loading tests both vertical and horizontal directions, a dynamic loading test, and cone penetration tests we re conducted for determining proper design parameters of the ground for the foundations. Design parameters were determined rationally based on the tests results. Rational design verification was obtained from this research.

  1. Experimental study on AR fiberglass connectors for bridges made of composite materials

    Directory of Open Access Journals (Sweden)

    Tolosana, N.

    2006-06-01

    Full Text Available One highly relevant aspect in composite material bridgedesing is the study of the shear connectors to be used.Composite material bridges most commonly comprise acomposite deck resting on steel or reinforced concrete girders.This article analyzes the connectors most frequentlyused in such bridges.It also reviews the connectors used in the King StormwaterChannel Bridge, whose fibreglass deck is supported bygirders made of concrete-filled carbon fibre girders.The paper advances proposals for several types of connectorsand discusses the results of push-out test run ona number of prototypes with different geometries.The results are analyzed to identify the optimum model forthe “Autovia del Cantabrico” Overpass, with its 46-m span,carbon fibre girders and AR glass shear connectors.Un aspecto relevante dentro del proyecto de un puenterealizado en materiales compuestos es el estudio de losconectores. El caso mas frecuente de puente en materialescompuestos es aquel que presenta un tablero de materialescompuestos soportado por vigas metalicas o de hormigonarmado. En este trabajo se analizaran los tipos deconectores mas utilizados en este tipo de puentesSe analizaran tambien los conectores utilizados en elKing Stormwater Channel Bridge, donde ademas deltablero en fibra de vidrio, se fabricaron las vigas en fibrasde carbono rellenas de hormigon.En este articulo se propondran varios tipos de conectoresy se presentaran los resultados experimentales correspondientesal ensayo de “push-out” de varios prototipos condiferentes geometrias.Tras evaluar los resultados, se determinara el mas idoneopara su implantacion en el Paso Superior de la Autovia delCantabrico, de 46 metros de luz y que presenta las vigasen fibra de carbono y los conectores de vidrio AR.

  2. Steel framing strategies for highly skewed bridges to reduce/eliminate distortion near skewed supports : [summary].

    Science.gov (United States)

    2014-05-01

    In the past, bridges were aligned normal to crossing roads or obstacles in order to simplify bridge construction. However, the continuing expansion of the interstate system has challenged engineers to provide more horizontal clearance, reduce right-o...

  3. Cable-stayed PC bridge with inclined main tower. Hachinohe port island bridge; Keisha shuto to yusuru 2 keikan renzoku PC shachokyo. Hachinoheko port island renrakykyo (kasho)

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, A. [Hachinohe Institute of Technology, Aomori (Japan)

    1994-09-15

    The design and construction of the inclined main bridge, which is being constructed at the mouth of the Hachinohe Harbor (in Japan), are outlined in this paper. This connecting bridge has an overall length of 265.56 m, and consists of the main bridge member of asymmetric 2 cable-stayed PC bridge and the 3 cable-stayed PC box member bridge. An asymmetric design was employed for the main bridge frame to ensure the access space for small ships passing between bridge girders, easy maintenance and service, improved economy, and excellent view. The main tower is a single-pillar reinforced concrete structure with an inclination of 15{degree} and 47 m in height. Forty-eight diagonal cables are arranged so that 12 cable trains are connected to the main tower on the right and left sides respectively, and the back-stay cable structure is used for each upper 3 cable trains to improve safety against the earthquake. The main beam is made by a prestressed concrete structure with inverse trapezoidal 3-chamber frame section. This structure is superior in increasing the safety against wind. Steel tube sheet-pile well is selected for the bridge pier base, and debris layer is selected as a support layer for the base. For the construction of the lower bridge section, sand conversion through predrilling of rubble-mound and debris layer was executed. The underwater non-separative concrete and embedded type frame are used around the bridge piers and its surrounding. For the construction of the upper bridge section, steel frames are used inside the main tower to ensure the construction precision. 7 figs.

  4. Gust loading on streamlined bridge decks

    DEFF Research Database (Denmark)

    Larose, Guy; Mann, Jakob

    1998-01-01

    The current analytical description of the buffeting action of wind on long-span bridges is based on the strip assumption. However, recent experiments on closed-box girder bridge decks have shown that this assumption is not valid and is the source of an important part of the error margin...... of the analytical prediction methods. In this paper, an analytical model that departs from the strip assumption is used to describe the gust loading on a thin airfoil. A parallel is drawn between the analytical model and direct measurements of gust loading on motionless closed-box girder bridge decks. Empirical...

  5. An Automated Sensing System for Steel Bridge Inspection Using GMR Sensor Array and Magnetic Wheels of Climbing Robot

    Directory of Open Access Journals (Sweden)

    Rui Wang

    2016-01-01

    Full Text Available Corrosion is one of the main causes of deterioration of steel bridges. It may cause metal loss and fatigue cracks in the steel components, which would lead to the collapse of steel bridges. This paper presents an automated sensing system to detect corrosion, crack, and other kinds of defects using a GMR (Giant Magnetoresistance sensor array. Defects will change the relative permeability and electrical conductivity of the material. As a result, magnetic field density generated by ferromagnetic material and the magnetic wheels will be changed. The defects are able to be detected by using GMR sensor array to measure the changes of magnetic flux density. In this study, magnetic wheels are used not only as the adhesion device of the robot, but also as an excitation source to provide the exciting magnetic field for the sensing system. Furthermore, compared to the eddy current method and the MFL (magnetic flux leakage method, this sensing system suppresses the noise from lift-off value fluctuation by measuring the vertical component of induced magnetic field that is perpendicular to the surface of the specimen in the corrosion inspection. Simulations and experimental results validated the feasibility of the system for the automated defect inspection.

  6. STUDY OF BRIDGE DECK A REVIEW

    OpenAIRE

    MISS. KSHITIJA S. BALWAN , MR. V. G. KHURD , MR. S. S. CHOUGULE

    2018-01-01

    The objective of this study was to understand the meaning of bridge deck. To know the different forms of decks used in bridge design. To understand different methods used for analysis of deck and study of box girder and its evolution

  7. Analysis of Biaxially Stressed Bridge Deck Plates

    DEFF Research Database (Denmark)

    Jönsson, Jeppe; Bondum, Tommi Højer

    2012-01-01

    The ultimate state analysis of bridge deck plates at the intersection zone between main girders and transverse beams is complicated by biaxial membrane stresses, which may be in compression or tension in either direction depending on the bridge configuration and the specific location. This paper...

  8. Study on Performance of Steel Fiber Concrete Bridge Pier Specimens under Horizontal Cyclic Loading

    Directory of Open Access Journals (Sweden)

    Baiben Chen

    2017-01-01

    Full Text Available Because of that steel fiber can effectively prevent the extension and development of small cracks in the concrete, steel fiber reinforced concrete has good toughness and tensile strength. In the application of building materials, steel fiber reinforced concrete is an ideal elastic-plastic material. For the seismic performance, it has advantages. In order to analyze the seismic performance of steel fiber reinforced concrete, 4 piers of the scale model test under horizontal cyclic loading were done. The results showed that failure mode of steel fiber reinforced concrete is better than that of ordinary concrete, and has a large yield moment under the external loads.

  9. Cluster analysis of stress corrosion mechanisms for steel wires used in bridge cables through acoustic emission particle swarm optimization.

    Science.gov (United States)

    Li, Dongsheng; Yang, Wei; Zhang, Wenyao

    2017-05-01

    Stress corrosion is the major failure type of bridge cable damage. The acoustic emission (AE) technique was applied to monitor the stress corrosion process of steel wires used in bridge cable structures. The damage evolution of stress corrosion in bridge cables was obtained according to the AE characteristic parameter figure. A particle swarm optimization cluster method was developed to determine the relationship between the AE signal and stress corrosion mechanisms. Results indicate that the main AE sources of stress corrosion in bridge cables included four types: passive film breakdown and detachment of the corrosion product, crack initiation, crack extension, and cable fracture. By analyzing different types of clustering data, the mean value of each damage pattern's AE characteristic parameters was determined. Different corrosion damage source AE waveforms and the peak frequency were extracted. AE particle swarm optimization cluster analysis based on principal component analysis was also proposed. This method can completely distinguish the four types of damage sources and simplifies the determination of the evolution process of corrosion damage and broken wire signals. Copyright © 2017. Published by Elsevier B.V.

  10. Dual Mode Sensing with Low-Profile Piezoelectric Thin Wafer Sensors for Steel Bridge Crack Detection and Diagnosis

    Directory of Open Access Journals (Sweden)

    Lingyu Yu

    2012-01-01

    Full Text Available Monitoring of fatigue cracking in steel bridges is of high interest to many bridge owners and agencies. Due to the variety of deterioration sources and locations of bridge defects, there is currently no single method that can detect and address the potential sources globally. In this paper, we presented a dual mode sensing methodology integrating acoustic emission and ultrasonic wave inspection based on the use of low-profile piezoelectric wafer active sensors (PWAS. After introducing the research background and piezoelectric sensing principles, PWAS crack detection in passive acoustic emission mode is first presented. Their acoustic emission detection capability has been validated through both static and compact tension fatigue tests. With the use of coaxial cable wiring, PWAS AE signal quality has been improved. The active ultrasonic inspection is conducted by the damage index and wave imaging approach. The results in the paper show that such an integration of passive acoustic emission detection with active ultrasonic sensing is a technological leap forward from the current practice of periodic and subjective visual inspection and bridge management based primarily on history of past performance.

  11. Dynamic response of a monorail steel bridge under a moving train

    Science.gov (United States)

    Lee, C. H.; Kawatani, M.; Kim, C. W.; Nishimura, N.; Kobayashi, Y.

    2006-06-01

    This study proposes a dynamic response analysis procedure for traffic-induced vibration of a monorail bridge and train. Each car in the monorail train is idealized as a dynamic system of 15-degrees-of-freedom. The governing equations of motion for a three-dimensional monorail bridge-train interaction system are derived using Lagrange's formulation for monorail trains, and a finite-element method for modal analysis of monorail bridges. Analytical results on dynamic response of the monorail train and bridge are compared with field-test data in order to verify the validity of the proposed analysis procedure, and a positive correlation is found. An interesting feature of the monorail bridge response is that sway motion is caused by torsional behavior resulting from eccentricity between the shear center of the bridge section and the train load.

  12. Evaluation of Radiation Exposure during Construction and Operation of Concrete Bridge Reinforced with Very Low Level Radioactive Steel

    International Nuclear Information System (INIS)

    Panik, M.; Necas, V.

    2012-01-01

    A lot of nuclear power plants are approaching the end of their lifetime and they will be phased out. Decommissioning of these nuclear power plants involve complete dismantling of technologies and demolition of buildings. During this process it is produced plenty of waste material of different categories. Significant portion of decommissioning materials comprise radionuclides what is caused by contamination and activation processes mostly from the operational period of nuclear power plant. Attention in this paper is paid to waste steel from the decommissioning of nuclear power plants with the specific activity just slightly exceeding legislation limits for the unconditional release into the environment. From the traditional point of view this material should be treated, conditioned and disposed on the radioactive waste repository. Second possibility is to release this material conditionally and reuse it in chosen industrial application. Very low level radioactive steel scrap should be melted and melting products should be processed into products that can be applied in industry. First option requires considerable financial investment, human resources and repository capacity. Second option saves some financial funds and it enables to reuse and save potentially valuable material for the future. Paper comprises evaluation of external and internal exposure during construction and operation of concrete bridges that utilize very low level radioactive steel as part of their reinforcement. Two models of representative concrete bridges were created. External gamma exposure and exposure from inhalation and ingestion of radionuclides were calculated using suitable computational tools. VISIPLAN 3D ALARA planning tool was chosen for the calculation of external gamma exposure. Software GOLDSIM enables to calculate transport of radionuclides initially contained in conditionally released reinforcement steel through subsoil and sequential exposure of people caused by inhalation of

  13. Seismic Retrofitting of an Existing Steel Railway Bridge by Fluid Viscous Dampers

    Science.gov (United States)

    Gangopadhyay, Avijit; Ghosh, Aparna Dey

    2016-09-01

    There are over a lakh of bridges in the Indian Railways, many of which have become seismically deficient, either through aging or due to inadequate seismic design considerations. The extensive damage of bridges all over the world in recent earthquakes has propelled significant advancement in earthquake protection and retrofitting of bridges. Amongst various passive control systems that are reliable as well as cost-effective, Fluid Viscous Dampers (FVDs) are proving to be successful in bridge vibration control. Orificed FVDs, commercially available as Taylor Devices, have already been successfully installed in several bridges worldwide. However, there has been no such application or study related to Indian railway bridges. In this paper, an existing thirty years' old railway bridge in Jharkhand, India, has been analyzed in SAP2000v14 considering reduced stiffness and found deficient when subjected to spectrum-compatible accelerograms. Subsequent retrofitting of the bridge superstructure with FVDs has been carried out and the results indicate substantial reductions in the responses of the bridge deck.

  14. Seismic Performance of Multi-Span RC Railway Bridges

    DEFF Research Database (Denmark)

    Georgakis, Christos; Barrau, Xavier

    2008-01-01

    Presently, there is no clear method for determining the optimal railway bridge design for a particular ground type and expected seismic intensity. Four main types of RC bridge dominate the current multi-span railway bridge design trends – the Simply Supported Beam, Continuous Box-Girder (CBG), CBG...

  15. The Non-Destructive Test of Steel Corrosion in Reinforced Concrete Bridges Using a Micro-Magnetic Sensor

    Directory of Open Access Journals (Sweden)

    Hong Zhang

    2016-09-01

    Full Text Available This paper presents a non-destructive test method for steel corrosion in reinforced concrete bridges by using a 3-dimensional digital micro-magnetic sensor to detect and analyze the self-magnetic field leakage from corroded reinforced concrete. The setup of the magnetic scanning device and the measurement mode of the micro-magnetic sensor are introduced. The numerical analysis model is also built based on the linear magnetic charge theory. Compared to the self-magnetic field leakage data obtained from magnetic sensor-based measurement and numerical calculation, it is shown that the curves of tangential magnetic field at different lift-off height all intersect near the edge of the steel corrosion zone. The result indicates that the intersection of magnetic field curves can be used to detect and evaluate the range of the inner steel corrosion in engineering structures. The findings of this work propose a new and effective non-destructive test method for steel corrosion, and therefore enlarge the application of the micro-magnetic sensor.

  16. Assessment of Replacement Bridge using Proof Load Test

    Science.gov (United States)

    Sundru, Saibabu

    2017-11-01

    This work begins with an overview of the condition assessment of old bridge and explained reasons for demolishing of the bridge. Briefly presented flexural analysis of two stage post-tensioned prestressed concrete girder, which will be replace the old (new bridge). Construction of I-girder and composite girder at first stage and second stage prestressing respectively is explained with figures. Assessment of the load-caring capacity of the one span of the replacement bridge with simple supports using proof load test is presented which is mandatory according to Indian standards. Weighted sand bags were used to load the bridge up to a predetermined service load with impact factor. Deflections of the I-girders of the bridge were measured at selected locations along and across the bridge span and compared with computed values. Linear response was observed during loading and unloading. Considering the load test results, theoretical estimation and criteria as stipulated in codes of practice, it can be inferred that prestressed concrete I-girder bridge span has adequate capacity to carry the loads and hence, deemed to have passed the test.

  17. Wireless Impedance Sensor with PZT-Interface for Prestress-Loss Monitoring in Prestressed Concrete Girder

    International Nuclear Information System (INIS)

    Nguyen, Khac Duy; Lee, So Young; Kim, Jeong Tae

    2011-01-01

    Ensuring the designed prestress force is very important for the safety of prestressed concrete bridge. The loss of prestress force in tendon could significantly reduce load carrying capacity of the structure. In this study, an automated prestress-loss monitoring system for prestressed concrete girder using PZT-interface and wireless impedance sensor node is presented. The following approaches are carried out to achieve the objective. Firstly, wireless impedance sensor nodes are designed for automated impedance-based monitoring technique. The sensor node is mounted on the high-performance Imote2 sensor platform to fulfill high operating speed, low power requirement and large storage memory. Secondly, a smart PZT-interface designed for monitoring prestress force is described. A linear regression model is established to predict prestress-loss. Finally, a system of the PZT-interface interacted with the wireless sensor node is evaluated from a lab-scale tendon-anchorage connection of a prestressed concrete girder

  18. Committee VI.1. Extreme Hull Girder Loading

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher

    2000-01-01

    Committee Mandate. Evaluate and develop direct calculation procedures for extreme wawe loads on ship hull girders. Due consideration shall be given to stochastic and non-linear effects. The procedures shall be assessed by comparison with in-service experiences, model tests and more refined...

  19. Impact on the environment from steel bridge paint deterioration using lead isotopic tracing, paint compositions and soil deconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Gulson, Brian, E-mail: brian.gulson@mq.edu.au [Department of Environmental Science, Macquarie University, Sydney, NSW 2109 (Australia); CSIRO Energy Flagship, North Ryde, NSW 2113 (Australia); Chiaradia, Massimo [Department of Mineralogy, University of Geneva, Geneva (Switzerland); Davis, Jeffrey [CSIRO Energy Flagship, North Ryde, NSW 2113 (Australia); O' Connor, Gary [Queensland Department of Environment & Heritage Protection, Brisbane, QLD 4000 (Australia)

    2016-04-15

    Deterioration and repair of lead paint on steel structures can result in contamination of the ambient environment but other sources of lead such as from past use of leaded paint and gasoline and industrial activities can also contribute to the contamination. Using a combination of high precision lead isotopic tracing, detailed paint examination, including with scanning electron microscopy, and soil deconstruction we have compared paint on a steel bridge and bulk soil and lead-rich particles separated from soil. The majority of Pb found in the paint derives from Australian sources but some also has a probable US origin. The isotopic data for the bulk soils and selected particles lie on a mixing line with end members the geologically ancient Broken Hill lead and possible European lead which is suggested to be derived from old lead paint and industrial activities. Data for gasoline-derived particulates lie on this array and probably contribute to soil Pb. Although paint from the bridge can be a source of lead in the soils, isotopic tracing, paint morphology and mineralogical identification indicate that other sources, including from paint, gasoline and industrial activities, are contributing factors to the lead burden. Even though physical characteristics and elemental composition are the same in some particles, the isotopic signatures demonstrate that the sources are different. Plots using {sup 206}Pb/{sup 208}Pb vs {sup 206}Pb/{sup 207}Pb ratios, the common representation these days, do not allow for source discrimination in this investigation. - Highlights: • Soil Pb values up to 1200 mg/kg below Pb painted bridge • Microscopy & SEM characterised up to 6 different paint layers. • Isotopes identified different sources of Pb including paint and gasoline. • Multiple methods provide definitive answers.

  20. A technical report on structural evaluation of the Meade County reinforced concrete bridge : research [summary].

    Science.gov (United States)

    2009-01-01

    Meade County Bridge is a two-lane highway reinforced concrete bridge with two girders each with 20 continuous spans. The bridge was built in 1965. It has been reported that in early years of the bridge service period, a considerable amount of cracks ...

  1. Field vibration test of a long-span cable-stayed bridge by large exciters. Daishinpuku kashin ni yoru chodai shachokyo no jikkyo shindo jikken

    Energy Technology Data Exchange (ETDEWEB)

    Okauchi, I. (Chuo University, Tokyo (Japan). Faculty of Science and Engineering); Miyata, T. (Yokohama National University, Yokohama (Japan). Faculty of Engineering); Sasaki, N. (Mitsubishi Heavy Industries, Ltd., Tokyo (Japan)); Tatsumi, M.

    1992-10-15

    Long-span cable-stayed bridge requires indispensably discussions on safety against gale and earthquake, and correct assessment on its inherent vibration characteristics at the design stage is critical. However, theoretical assessment on structural decay is difficult, hence it is desirable to make measurement and verification upon its completion. This paper reports the result of measurements and considerations on a three-span continuous steel cable-stayed bridge with a length of 790 m (185 m + 420 m + 185 m) spanning between Hitsuishi Island and Iwakuro Island in the Kojima-Sakaide route of the Honshu-Shikoku connecting bridge. Large shaking machines were used to give girders vibrations with large amplitudes (10 cm at maximum), and high-accuracy measurements were made. The measurements verified the reasonability of the dynamic design for the bridge. The measured value of the logarithmic decay rate [delta] as the major experimental data presented that bending vibration is large as a whole, with torsional vibration somewhat smaller, and all the design values were on safety side. Confirmation was made on amplitude dependence of the decay rate, the inherent modes of low-order vibrations, and coupled behaviors among the girders, cables, and towers. 16 refs., 13 figs., 3 tabs.

  2. History of Connecticut's short-term strain program for evaluation of steel bridges : July 2009.

    Science.gov (United States)

    2009-07-01

    Non-destructive strain monitoring has been used for two decades on Connecticuts bridges to : supplement visual field inspections. These studies have addressed a wide range of problems, : including fatigue cracking in diaphragm connections, cracked...

  3. Hollow-Core FRP–Concrete–Steel Bridge Columns under Torsional Loading

    Directory of Open Access Journals (Sweden)

    Sujith Anumolu

    2017-11-01

    Full Text Available This paper presents the behavior of hollow-core fiber-reinforced polymer–concrete–steel (HC-FCS columns under cyclic torsional loading combined with constant axial load. The HC-FCS consists of an outer fiber-reinforced polymer (FRP tube and an inner steel tube, with a concrete shell sandwiched between the two tubes. The FRP tube was stopped at the surface of the footing, and provided confinement to the concrete shell from the outer direction. The steel tube was embedded into the footing to a length of 1.8 times the diameter of the steel tube. The longitudinal and transversal reinforcements of the column were provided by the steel tube only. A large-scale HC-FCS column with a diameter of 24 in. (610 mm and applied load height of 96 in. (2438 mm with an aspect ratio of four was investigated during this study. The study revealed that the torsional behavior of the HC-FCS column mainly depended on the stiffness of the steel tube and the interactions among the column components (concrete shell, steel tube, and FRP tube. A brief comparison of torsional behavior was made between the conventional reinforced concrete columns and the HC-FCS column. The comparison illustrated that both column types showed high initial stiffness under torsional loading. However, the HC-FCS column maintained the torsion strength until a high twist angle, while the conventional reinforced concrete column did not.

  4. Dynamic Response of a Long-Span Concrete-Filled Steel Tube Tied Arch Bridge and the Riding Comfort of Monorail Trains

    Directory of Open Access Journals (Sweden)

    Hongye Gou

    2018-04-01

    Full Text Available In this study, a dynamic response analysis procedure is proposed and applied to investigate the dynamic responses of a straddle-type concrete-filled steel tube tied arch bridge under train and truck loadings. A numerical model of the coupled monorail train–bridge system is established to investigate the dynamic behaviors of the bridge under moving trains. A refined three-dimensional finite element model is built for the bridge and a 15 degrees-of-freedom vehicle model is presented for the train. The numerical model is validated using in-situ test results and then used to analyze the dynamic displacement and acceleration of the bridge and the trains on the bridge. Based on the simulation results, the impact factor of the bridge is investigated and the riding comfort of the trains is evaluated. The investigation results show that the impact factor of vehicle loads reaches the maximum value when the resonance of the bridge is induced by the moving vehicles. The effect of train braking predominates the longitudinal vibration of the bridge but is negligible in the transverse and vertical directions. The vehicle speed is the dominating factor for the riding comfort of the train.

  5. Digital image rectification tool for metrification of gusset plate connections in steel truss bridges.

    Science.gov (United States)

    2009-03-01

    A method was developed to obtain dimensional data from photographs for analyzing steel truss gusset plate : connections. The method relies on a software application to correct photographic distortion and to scale the : photographs for analysis. The a...

  6. Design and construction of Ogawa bridge; Ogawa bashi no sekkei to seko

    Energy Technology Data Exchange (ETDEWEB)

    Hori, T.; Chigira, F. [Kajima Corp., Tokyo (Japan); Sakao, H.

    1995-09-30

    Ogawa bridge 230m long by 15.5m wide has been planned on the national road No.401 at Katashina-mura in Gunma Prefecture. Structure mode is two spans continuous PC cable-stayed obliquely system, and a main tower is H type (height: 56m from the road surface) and is located at the center of the bridge alone. This place corresponding to the entrance of Oze famous national park, the main tower is designed so as to have bulge, imaging Mizubasho (lysichiton camtschatcense), from the middle part of the pier to the lower part of the main tower. Arrangement of the cables is designed as two faces of hung fun type and one side face is composed of 13 steel strands (dia. 15.2mm wire x 27 (partly 19); covered with PE tube) in front and rear respectively. A main girder is the box type PC block 2.3m height by 4m or 3m long, and 3m long one is for fastening with a cable. Centering on the main tower, the girder blocks are successively connected in front and rare alternatively and are fastened with cables in part. This overhanging connection work is carried out by two special movable conveyers `Wagens`. 26 figs., 2 tabs.

  7. Seismic damage sensing of bridge structures with TRIP reinforcement steel bars

    Science.gov (United States)

    Adachi, Yukio; Unjoh, Shigeki

    2001-07-01

    Intelligent reinforced concrete structures with transformation-induced-plasticity (TRIP) steel rebars that have self-diagnosis function are proposed. TRIP steel is special steel with Fe-Cr based formulation. It undergoes a permanent change in crystal structure in proportion to peak strain. This changes from non-magnetic to magnetic steel. By using the TRIP steel rebars, the seismic damage level of reinforced concrete structures can be easily recognized by measuring the residual magnetic level of the TRIP rebars, that is directly related to the peak strain during a seismic event. This information will be most helpful for repairing the damaged structures. In this paper, the feasibility of the proposed intelligent reinforced concrete structure for seismic damage sensing is experimentally studied. The relation among the damage level, peak strain of rebars, and residual magnetic level of rebars of reinforced concrete beams implemented with TRIP steel bars was experimentally studied. As the result of this study, this intelligent structure can diagnose accumulated strain/damage anticipated during seismic event.

  8. Bridge condition assessment based on long-term strain monitoring

    Science.gov (United States)

    Sun, LiMin; Sun, Shouwang

    2011-04-01

    In consideration of the important role that bridges play as transportation infrastructures, their safety, durability and serviceability have always been deeply concerned. Structural Health Monitoring Systems (SHMS) have been installed to many long-span bridges to provide bridge engineers with the information needed in making rational decisions for maintenance. However, SHMS also confronted bridge engineers with the challenge of efficient use of monitoring data. Thus, methodologies which are robust to random disturbance and sensitive to damage become a subject on which many researches in structural condition assessment concentrate. In this study, an innovative probabilistic approach for condition assessment of bridge structures was proposed on the basis of long-term strain monitoring on steel girder of a cable-stayed bridge. First, the methodology of damage detection in the vicinity of monitoring point using strain-based indices was investigated. Then, the composition of strain response of bridge under operational loads was analyzed. Thirdly, the influence of temperature and wind on strains was eliminated and thus strain fluctuation under vehicle loads is obtained. Finally, damage evolution assessment was carried out based on the statistical characteristics of rain-flow cycles derived from the strain fluctuation under vehicle loads. The research conducted indicates that the methodology proposed is qualified for structural condition assessment so far as the following respects are concerned: (a) capability of revealing structural deterioration; (b) immunity to the influence of environmental variation; (c) adaptability to the random characteristic exhibited by long-term monitoring data. Further examination of the applicability of the proposed methodology in aging bridge may provide a more convincing validation.

  9. Experimental use of Line-X coated steel pipe piles, Clay Hill Bridge (#2157) replacement project over the Mousam River, Route 9/Western Avenue, Kennebunk, Maine.

    Science.gov (United States)

    2013-02-01

    Steel pipe piles used by MaineDOT for bridge construction are typically coated with a fusion-bonded epoxy (FBE). FBE is a powder-based coating with properties similar to traditional : epoxies. Its name is derived from the process by which it adheres ...

  10. Erection of the Meiko-Central bridge; Meiko chuo ohashi no kasetsu

    Energy Technology Data Exchange (ETDEWEB)

    Kaneda, S.; Nishikawa, K.; Nagai, Y.; Ishihara, S.; Tsunekawa, M.; Yoshino, S. [Kawasaki Heavy Industries, Ltd., Kobe (Japan)

    1997-10-20

    This is a 1170m-long triple-span continuous steel cable-stayed bridge with the central span measuring 590m, built to traverse Nagoya Port as part of the Isewangan highway. The 190m-high main towers are A-shaped, and have an octagonal cross section to stay stable against winds. The joints were designed to be welded mainly on the spot so as not to affect the surrounding landscape, and in this welding process the achievement of prescribed accuracy was the important technological task. The main girder was a 37m-wide multi-chamber/single-box type, and the steel stabs were installed by on-site welding. Since the erection was carried out above the ship course, a method was used in which the main girder was hung over with the cable stretched long, which demanded constant prudence to assure accuracy throughout the work. The cable is a 17-stage 2-face multi-fan type, a semi-parallel wire strand coated with polyethylene and white fluoroethylene resin. As for accuracy management for erection, it was accomplished by adjusting the amount of shim introduced into each of the four cables every time one stage of cable was erected for the side span and central span. Every accuracy management requirement met the target value with an adequate margin. 6 refs., 10 figs., 4 tabs.

  11. Experiment on interface separation detection of concrete-filled steel tubular arch bridge using accelerometer array

    Science.gov (United States)

    Pan, Shengshan; Zhao, Xuefeng; Zhao, Hailiang; Mao, Jian

    2015-04-01

    Based on the vibration testing principle, and taking the local vibration of steel tube at the interface separation area as the study object, a real-time monitoring and the damage detection method of the interface separation of concrete-filled steel tube by accelerometer array through quantitative transient self-excitation is proposed. The accelerometers are arranged on the steel tube area with or without void respectively, and the signals of accelerometers are collected at the same time and compared under different transient excitation points. The results show that compared with the signal of compact area, the peak value of accelerometer signal at void area increases and attenuation speed slows down obviously, and the spectrum peaks of the void area are much more and disordered and the amplitude increases obviously. whether the input point of transient excitation is on void area or not is irrelevant with qualitative identification results. So the qualitative identification of the interface separation of concrete-filled steel tube based on the signal of acceleration transducer is feasible and valid.

  12. Long-term behaviour of a steel-concrete composite railway bridge deck

    OpenAIRE

    STAQUET, S; TAILHAN, JL; ESPION, B

    2005-01-01

    A prefabricated, composite and prestressed railway bridge deck has been instrumented in June 2000 with strain gages and vibrating wire extensometers. The purpose of this paper is to report on the comparison between strains recorded in situ up to four years with values computed within the framework of an original time-dependent analysis base on the evolution of the degree of hydration and the internal relative humidity in concrete. These fundamental parameters used in the proposed model to com...

  13. Instrument to determine prestress remaining in a damaged bridge girder

    Science.gov (United States)

    Civjan, Scott A.; Jirsa, James O.; Carrasquillo, Ramon L.; Fowler, David W.

    1998-03-01

    An instrument has been developed to estimate stress levels in prestress strands in existing members. The prototype instrument applies a lateral load to an exposed prestressing strand and measures the resulting displacements. The instrument was calibrated for 0.5-inch (12.7 mm) diameter seven-wire strand with exposed lengths of 1.5 feet (0.46 m) to 3.75 feet (1.14 m). It was tested to determine its accuracy, precision, and usefulness in the field. Strand forces were consistently estimated to within ten percent of the actual load. The device was also utilized in the placement of strand splices and was found to be more reliable in checking induced strand tensions than the standard torque wrench method.

  14. Self-compacting concrete for prestressed bridge girders

    Science.gov (United States)

    Erkmen, Bulent

    The purpose of this study was to examine social mobility as a motivation for first-generation college students in reaching attainment at two-year technical colleges. The research question was to what degree has the perception of social mobility influenced first generation college students at technical colleges to complete their career educational goals. Graduates of a two-year technical college were asked a series of open-ended questions regarding their past experiences and perceptions of attending and completing a two-year technical college program; their childhood perceptions of their social status; and experiences with family members regarding their change in social class status. These questions were designed to determine their feelings, viewpoints, reflections, experiences, struggles, and thoughts about attainment (completing their post-secondary education) and the extent to which social mobility influenced their decision to complete their education. The benefits of this research include an understanding of social mobility and educational attainment. Results of this study could be used to better understand the process that first generation college students go through in order to attain their educational goals. The information from this study may be useful for technical college administrations to help design programs and processes for future first-generation college students' success and aid in retention of these students.

  15. End region detailing of pretensioned concrete bridge girders : [summary].

    Science.gov (United States)

    2013-03-01

    Introduction of the Florida-I Beam (FIB) in 2009 renewed interest in prestressed concrete beam design, especially end region details. In this study, University of Florida researchers examined construction detailing at the FIB end region.

  16. Neighborhood level health risk assessment of lead paint removal activities from elevated steel bridges

    Energy Technology Data Exchange (ETDEWEB)

    Conway, R.F.; Cohen, J.T.; Bowers, T.

    1999-07-01

    The New York City Department of Transportation (NYCDOT) has adopted strict containment and monitoring procedures during paint removal activities on its bridges because of the increasing awareness about lead poisoning in children in urban environments and the potential risk of lead-based paint releases during those activities. NYCDOT owns nearly 800 bridges scattered throughout New York City. Before undertaking paint removal activities as part of its ongoing preventive maintenance and rehabilitation program, NYCDOT recently conducted an analysis to determine the public health risk posed to children living near them. The analysis the first of its kind to assess the actual public health risk potential during both routine operations and upset conditions, or accidental releases evaluated the total and incremental blood lead levels from paint removal activities on more than 5,000 children from 6 months to 6 years old. Increases in baseline blood lead levels were estimated using several models, including EPA's Integrated Exposure Uptake Biokinetic (IEUBK) Model. This model estimates steady-state blood lead levels in children, reflecting exposure to lead in multiple media over an extended period of time. Increases in lead exposure from paint removal activities in the area surrounding the bridges was estimated using EPA's Industrial Source Complex (ISC3) model to calculate ambient air and deposition levels. Potential releases from the containment and ancillary equipment used in the paint removal process were modeled based on different release scenarios ranging from routine operations to complete failure of containment. To estimate the paint removal activities' contribution to long-term exterior dust lead levels (and its related interior component), a stochastic simulation model was developed for each block in the study area.

  17. Fatigue strength of the joint between diaphragms and longitudinal ribs in box section girders; Hako danmen keta no diaphragm to shita flange tateribu no kosabu no hiro kyodo

    Energy Technology Data Exchange (ETDEWEB)

    Miki, C.; Shiozaki, M.; Takeishi, K. [Tokyo Institute of Technology, Tokyo (Japan). Faculty of Engineering; Ohashi, H. [Honshu-Shikoku Bridge Authority, Tokyo (Japan)

    1997-04-21

    Discussions were given on crossing joints of diaphragms on hanger fixing sections and U-ribs on lower flanges in reinforcing box girders of a suspension bridge, as to their local stress generating behavior and effects of cope holes on fatigue strength. The test pieces have dimensions and shapes modeling the crossing joints, and the steel materials are SM490YA for upper and lower flanges and webs, and SS400 for U-ribs. The loading test was performed with four-point bending and at loading amplitudes of 30 to 45 tf. Furthermore, stress analysis was conducted by using the finite element method. The following conclusions were obtained as a result: local stress at cope hole tips decreases and fatigue strength increases with the smaller the cope hole diameter; when the cope holes are back-filled completely, deformation is concentrated on welds of the U-ribs and the flanges, generating high local stress; this reduces significantly the fatigue strength of details having no cope holes; and no particular differences are found on effects of boxing of the cope hole tips on the fatigue strength. 7 refs., 10 figs., 3 tabs.

  18. Seismic fragility curves of bridge piers accounting for ground motions in Korea

    Science.gov (United States)

    Nguyen, Duy-Duan; Lee, Tae-Hyung

    2018-04-01

    Korea is located in a slight-to-moderate seismic zone. Nevertheless, several studies pointed that the peak earthquake magnitude in the region can be reached to approximately 6.5. Accordingly, a seismic vulnerability evaluation of the existing structures accounting for ground motions in Korea is momentous. The purpose of this paper is to develop seismic fragility curves for bridge piers of a steel box girder bridge equipped with and without base isolators based on a set of ground motions recorded in Korea. A finite element simulation platform, OpenSees, is utilized to perform nonlinear time history analyses of the bridges. A series of damage states is defined based on a damage index which is expressed in terms of the column displacement ductility ratio. The fragility curves based on Korean motions were thereafter compared with the fragility curves generated using worldwide earthquakes to assess the effect of the two ground motion groups on the seismic fragility curves of the bridge piers. The results reveal that both non- and base-isolated bridge piers are less vulnerable during the Korean ground motions than that under worldwide earthquakes.

  19. Structural behavior of concrete box bridge using embedded FBG sensors

    Science.gov (United States)

    Chung, Wonseok; Kang, Donghoon

    2012-04-01

    For the structural monitoring of railway bridges, electromagnetic interference (EMI) is a significant problem as modern railway lines are powered by high-voltage electric power feeding systems. Fiber optic sensing systems are free from EMI and have been successfully applied in civil engineering fields. This study presents the application of fiber Bragg grating (FBG)-based sensing systems to precast concrete box railway bridges. A 20 m long full-scale precast concrete box railway girder was fabricated and tested in order to identify its static performance. The experimental program involved the measurement of the nonlinear static behavior until failure. Multiplexed FBG strain sensors were embedded along the length of steel rebar and a strain-induced wavelength shift was measured in order to monitor internal strains. The measured values from the FBG-based sensors are compared with the results using electric signal-based sensors. The results show that the FBG sensing system is promising and can improve the efficiency of structural monitoring for modern railway bridges.

  20. Active Control of Long Bridges Using Flaps

    DEFF Research Database (Denmark)

    Hansen, H. I.; Thoft-Christensen, Palle

    The main problem in designing ultra-long span suspension bridges is flutter. A solution to this problem might be to introduce an active flap control system to increase the flutter wind velocity. The investigated flap control system consists of flaps integrated in the bridge girder so each flap...... is the streamlined part of the edge of the girder. Additional aerodynamic derivatives are shown for the flaps and it is shown how methods already developed can be used to estimate the flutter wind velocity for a bridge section with flaps. As an example, the flutter wind velocity is calculated for different flap...... configurations for a bridge section model by using aerodynamic derivatives for a flat plate. The example shows that different flap configurations can either increase or decrease the flutter wind velocity. for optimal flap configurations flutter will not occur....

  1. Failure Load Test of a CFRP Strengthened Railway Bridge in Oumlrnskoumlldsvik, Sweden

    DEFF Research Database (Denmark)

    Täljsten, Björn; Bergström, Markus; Carolin, Anders

    2009-01-01

    using carbon fiber reinforced polymer (CFRP) rectangular rods epoxy bonded in sawed up slots, e.g., near surface mounted reinforcement. The strengthening was very successful and resulted in a desired shear failure when the bridge was loaded to failure. The load-carrying capacity in bending...... steel reinforcement by approximately 10%, and increased the height of the compressed zone by 100 mm. When the shear failure occurred, the utilization of the compression concrete and CFRP rods were 100 and 87.5%, respectively. This indicates that a bending failure indeed was about to occur, even though......, Sweden is presented. In this particular test the shear capacity of the concrete girders was of primary interest. However, for any reasonable placement of the load (a line load placed transverse to the track direction) a bending failure would occur. This problem was solved by strengthening for flexure...

  2. Modal analysis of railway bridge hangers using artificial and ambient excitation

    Science.gov (United States)

    Link, M.; Weiland, M.; Yu, F.

    2002-12-01

    This paper describes the methods used and results obtained from analysing some resonance phenomena which were observed on a steel railway bridge. These phenomena were visible on the slender hangers connecting the arch girder and the main truss girder under certain wind conditions. The paper describes the set up of a vibration monitoring system designed to measure the vibration response of the hangers together with the wind velocity and the wind direction over a period of several months under operational conditions. These data should yield the basis for correlating the wind and the structural characteristics. In addition artificial impulse hammer excitation was used to measure the modal characteristics (natural frequencies and modes of the hangers separately. The results of these tests compared well with those obtained from applying some “output only" modal identification techniques to the operational response data with unknown excitation forces. The results also compared well to analytical predictions and were used to identify the axial forces in the hangers by updating the axial force minimising the test/analysis deviations. The results allowed to estimate the fatigue life of the hangers confirming the need for the design of anti- vibration devices.

  3. Steel

    International Nuclear Information System (INIS)

    Zorev, N.N.; Astafiev, A.A.; Loboda, A.S.; Savukov, V.P.; Runov, A.E.; Belov, V.A.; Sobolev, J.V.; Sobolev, V.V.; Pavlov, N.M.; Paton, B.E.

    1977-01-01

    Steels also containing Al, N and arsenic, are suitable for the construction of large components for high-power nuclear reactors due to their good mechanical properties such as good through-hardening, sufficiently low brittleness conversion temperature and slight displacement of the latter with neutron irradiation. Defined steels and their properties are described. (IHOE) [de

  4. The Impact of the HMCFRP Ratio on the Strengthening of Steel Composite I-Beams

    Directory of Open Access Journals (Sweden)

    E. Agcakoca

    2012-01-01

    Full Text Available Carbon fiber-reinforced polymer materials have become popular in the construction industry during the last decade for their ability to strengthen and retrofit concrete structures. The recent availability of high-modulus carbon fiber-reinforced polymer strips (HMCFRP has opened up the possibility of using this material in strengthening steel structures as well. The strips can be used in steel bridge girders and structures that are at risk of corrosion-induced cross-sectional losses, structural deterioration from aging, or changes in function. In this study, a set of bending experiments was performed on three types of steel beams reinforced with HMCFRP. The results were used to enhance a nonlinear finite element model built with ABAQUS software. The accuracy of the mathematical models for HMCFRP, epoxy, and steel profiles was compared with the experimental results, and the ability of HMCFRP to continue carrying load from the steel beams during rupture and postrupture scenarios was observed using numerical analysis. Using these verified finite element models, a parametric analysis was performed on the HMCFRP failure modes and the quantity to be used with IPE profile steel beams. The maximum amount of HMCFRP needed for strengthening was determined, and an upper limit for its use was calculated to avoid any debonding failure of the fiber material.

  5. Reflective Cracking between Precast Prestressed Box Girders

    Science.gov (United States)

    2017-06-30

    The adjacent precast prestressed concrete box-beam bridge is the bridge of choice for short and short-to-medium span bridges. This choice is because of the ease of construction, favorable span-to-depth ratios, aesthetic appeal, and high torsional sti...

  6. Students design composite bridges

    NARCIS (Netherlands)

    Stark, J.W.B.; Galjaard, J.C.; Brekelmans, J.W.P.M.

    1999-01-01

    The paper gives an overview of recent research on steel-concrete composite bridge design by students of Delft University of Technology doing their master's thesis. Primary objective of this research was to find possibilities for application of steel-concrete composite bridges in the Netherlands,

  7. Discussion on the installation checking method of precast composite floor slab with lattice girders

    Science.gov (United States)

    Chen, Li; Jin, Xing; Wang, Yahui; Zhou, Hele; Gu, Jianing

    2018-03-01

    Based on the installation checking requirements of China’s current standards and the international norms for prefabricated structural precast components, it proposed an installation checking method for precast composite floor slab with lattice girders. By taking an equivalent composite beam consisted of a single lattice girder and the precast concrete slab as the checking object, compression instability stress of upper chords and yield stress of slab distribution reinforcement at the maximum positive moment, tensile yield stress of upper chords, slab normal section normal compression stress and shear instability stress of diagonal bars at the maximum negative moment were checked. And the bending stress and deflection of support beams, strength and compression stability bearing capacity of the vertical support, shear bearing capacity of the bolt and compression bearing capacity of steel tube wall at the bolt were checked at the same time. Every different checking object was given a specific load value and load combination. Application of installation checking method was given and testified by example.

  8. Fatigue of cable anchorage of large cable stayed bridge; Daikibo shachokyo cable teichaku kozo no hiro

    Energy Technology Data Exchange (ETDEWEB)

    Endo, T.; Matsumoto, T. [Honshu-Shikoku Bridge Authority, Tokyo (Japan); Tsukahara, H. [Yokogawa Bridge Corp., Tokyo (Japan); Miki, C. [Tokyo Institute of Technology, Tokyo (Japan)

    1995-10-21

    Design considerations such as design schemes, the assemblage and welding of steel plates, and safety for fatigue of welded connections have to be taken for the cable anchorages of the steel cable stayed bridges. In this study, two full scale models, which have different shape of box anchorages welded to the web of the main girder, were made to investigate fatigue characteristics as well as assemblage of plate and gelding details. Finite element analyses for both test models and actual bridges here carried out to compare stress distribution. It was confirmed that the assemblage and welding of both types of box anchorage were attainable kith required quality and accuracy. According to the fatigue test, fatigue cracks originated from the weldings of the bearing plate to which the load from cable socket applied directly were caused by out-of-plane bending of the bearing plate. It was proved that the slight modifications of the details around the bearing plate resulted in sufficient fatigue strength in both types of anchorage. 1 ref., 23 figs., 2 tabs.

  9. An overheight vehicle bridge collision monitoring system using piezoelectric transducers

    Science.gov (United States)

    Song, G.; Olmi, C.; Gu, H.

    2007-04-01

    With increasing traffic volume follows an increase in the number of overheight truck collisions with highway bridges. The detection of collision impact and evaluation of the impact level is a critical issue in the maintenance of a concrete bridge. In this paper, an overheight collision detection and evaluation system is developed for concrete bridge girders using piezoelectric transducers. An electric circuit is designed to detect the impact and to activate a digital camera to take photos of the offending truck. Impact tests and a health monitoring test were conducted on a model concrete bridge girder by using three piezoelectric transducers embedded before casting. From the experimental data of the impact test, it can be seen that there is a linear relation between the output of sensor energy and the impact energy. The health monitoring results show that the proposed damage index indicates the level of damage inside the model concrete bridge girder. The proposed overheight truck-bridge collision detection and evaluation system has the potential to be applied to the safety monitoring of highway bridges.

  10. A Finite Segment Method for Skewed Box Girder Analysis

    Directory of Open Access Journals (Sweden)

    Xingwei Xue

    2018-01-01

    Full Text Available A finite segment method is presented to analyze the mechanical behavior of skewed box girders. By modeling the top and bottom plates of the segments with skew plate beam element under an inclined coordinate system and the webs with normal plate beam element, a spatial elastic displacement model for skewed box girder is constructed, which can satisfy the compatibility condition at the corners of the cross section for box girders. The formulation of the finite segment is developed based on the variational principle. The major advantage of the proposed approach, in comparison with the finite element method, is that it can simplify a three-dimensional structure into a one-dimensional structure for structural analysis, which results in significant saving in computational times. At last, the accuracy and efficiency of the proposed finite segment method are verified by a model test.

  11. Wave induced extreme hull girder loads on containerships

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher; Pedersen, Preben Terndrup; Shi, Bill

    2009-01-01

    This paper provides simple but rational procedures for prediction of extreme wave – induced sectional hull girder forces with reasonable engineering accuracy. The procedures take into account main ship hull characteristics such as: length, breadth, draught, block coefficient, bow flare coefficient......, forward speed and hull flexibility. The vertical hull girder loads are evaluated for specific operational profiles. Firstly a quadratic strip theory is presented which can give separate predictions for the hogging and sagging bending moments and shear forces and for hull girder loads. Then this procedure...... is based on rational methods it can be applied for novel single hull ship types not presently covered by the rules of the classification societies or to account for specific operational profiles....

  12. Geometric nonlinear analysis of self-anchored cable-stayed suspension bridges.

    Science.gov (United States)

    Hui-Li, Wang; Yan-Bin, Tan; Si-Feng, Qin; Zhe, Zhang

    2013-01-01

    Geometric nonlinearity of self-anchored cable-stayed suspension bridges is studied in this paper. The repercussion of shrinkage and creep of concrete, rise-to-span ratio, and girder camber on the system is discussed. A self-anchored cable-stayed suspension bridge with a main span of 800 m is analyzed with linear theory, second-order theory, and nonlinear theory, respectively. In the condition of various rise-to-span ratios and girder cambers, the moments and displacements of both the girder and the pylon under live load are acquired. Based on the results it is derived that the second-order theory can be adopted to analyze a self-anchored cable-stayed suspension bridge with a main span of 800 m, and the error is less than 6%. The shrinkage and creep of concrete impose a conspicuous impact on the structure. And it outmatches suspension bridges for system stiffness. As the rise-to-span ratio increases, the axial forces of the main cable and the girder decline. The system stiffness rises with the girder camber being employed.

  13. Geometric Nonlinear Analysis of Self-Anchored Cable-Stayed Suspension Bridges

    Directory of Open Access Journals (Sweden)

    Wang Hui-Li

    2013-01-01

    Full Text Available Geometric nonlinearity of self-anchored cable-stayed suspension bridges is studied in this paper. The repercussion of shrinkage and creep of concrete, rise-to-span ratio, and girder camber on the system is discussed. A self-anchored cable-stayed suspension bridge with a main span of 800 m is analyzed with linear theory, second-order theory, and nonlinear theory, respectively. In the condition of various rise-to-span ratios and girder cambers, the moments and displacements of both the girder and the pylon under live load are acquired. Based on the results it is derived that the second-order theory can be adopted to analyze a self-anchored cable-stayed suspension bridge with a main span of 800 m, and the error is less than 6%. The shrinkage and creep of concrete impose a conspicuous impact on the structure. And it outmatches suspension bridges for system stiffness. As the rise-to-span ratio increases, the axial forces of the main cable and the girder decline. The system stiffness rises with the girder camber being employed.

  14. Timber in Bridge Structures

    OpenAIRE

    Detkin, Viktoria

    2016-01-01

    The purpose of this final year project was to study the properties of timber as a structural material and the suitability of wood in load bearing members for bridge structures. For a case study, an existing timber bridge was selected. Due to its condition the bridge should be replaced. The design of a new bridge with steel beams holding a glulam deck was made. During the case study the replacement of steel beams by glulam timber ones was discussed. Some calculations were made in order to ...

  15. Seismic assessment of a multi-span steel railway bridge in Turkey based on nonlinear time history

    Science.gov (United States)

    Yılmaz, Mehmet F.; Çağlayan, Barlas Ö.

    2018-01-01

    Many research studies have shown that bridges are vulnerable to earthquakes, graphically confirmed by incidents such as the San Fernando (1971 USA), Northridge (1994 USA), Great Hanshin (1995 Japan), and Chi-Chi (1999 Taiwan) earthquakes, amongst many others. The studies show that fragility curves are useful tools for bridge seismic risk assessments, which can be generated empirically or analytically. Empirical fragility curves can be generated where damage reports from past earthquakes are available, but otherwise, analytical fragility curves can be generated from structural seismic response analysis. Earthquake damage data in Turkey are very limited, hence this study employed an analytical method to generate fragility curves for the Alasehir bridge. The Alasehir bridge is part of the Manisa-Uşak-Dumlupınar-Afyon railway line, which is very important for human and freight transportation, and since most of the country is seismically active, it is essential to assess the bridge's vulnerability. The bridge consists of six 30 m truss spans with a total span 189 m supported by 2 abutments and 5 truss piers, 12.5, 19, 26, 33, and 40 m. Sap2000 software was used to model the Alasehir bridge, which was refined using field measurements, and the effect of 60 selected real earthquake data analyzed using the refined model, considering material and geometry nonlinearity. Thus, the seismic behavior of Alasehir railway bridge was determined and truss pier reaction and displacements were used to determine its seismic performance. Different intensity measures were compared for efficiency, practicality, and sufficiency and their component and system fragility curves derived.

  16. Seismic assessment of a multi-span steel railway bridge in Turkey based on nonlinear time history

    Directory of Open Access Journals (Sweden)

    M. F. Yılmaz

    2018-01-01

    Full Text Available Many research studies have shown that bridges are vulnerable to earthquakes, graphically confirmed by incidents such as the San Fernando (1971 USA, Northridge (1994 USA, Great Hanshin (1995 Japan, and Chi-Chi (1999 Taiwan earthquakes, amongst many others. The studies show that fragility curves are useful tools for bridge seismic risk assessments, which can be generated empirically or analytically. Empirical fragility curves can be generated where damage reports from past earthquakes are available, but otherwise, analytical fragility curves can be generated from structural seismic response analysis. Earthquake damage data in Turkey are very limited, hence this study employed an analytical method to generate fragility curves for the Alasehir bridge. The Alasehir bridge is part of the Manisa–Uşak–Dumlupınar–Afyon railway line, which is very important for human and freight transportation, and since most of the country is seismically active, it is essential to assess the bridge's vulnerability. The bridge consists of six 30 m truss spans with a total span 189 m supported by 2 abutments and 5 truss piers, 12.5, 19, 26, 33, and 40 m. Sap2000 software was used to model the Alasehir bridge, which was refined using field measurements, and the effect of 60 selected real earthquake data analyzed using the refined model, considering material and geometry nonlinearity. Thus, the seismic behavior of Alasehir railway bridge was determined and truss pier reaction and displacements were used to determine its seismic performance. Different intensity measures were compared for efficiency, practicality, and sufficiency and their component and system fragility curves derived.

  17. Parametric Study on Responses of a Self-Anchored Suspension Bridge to Sudden Breakage of a Hanger

    Directory of Open Access Journals (Sweden)

    Wenliang Qiu

    2014-01-01

    Full Text Available The girder of self-anchored suspension bridge is subjected to large compression force applied by main cables. So, serious damage of the girder due to breakage of hangers may cause the collapse of the whole bridge. With the time increasing, the hangers may break suddenly for their resistance capacities decrease due to corrosion. Using nonlinear static and dynamic analysis methods and adopting 3D finite element model, the responses of an actual self-anchored suspension bridge to sudden breakage of hangers are studied in this paper. The results show that the sudden breakage of a hanger causes violent vibration and large changes in internal forces of the bridge. In the process of the vibration, the maximum tension of hanger produced by breakage of a hanger exceeds 2.22 times its initial value, and the reaction forces of the bearings increase by more than 1.86 times the tension of the broken hanger. Based on the actual bridge, the influences of some factors including flexural stiffness of girder, torsion stiffness of girder, flexural stiffness of main cable, weight of girder, weight of main cable, span to sag ratio of main cable, distance of hangers, span length, and breakage time of hanger on the dynamic responses are studied in detail, and the influencing extent of the factors is presented.

  18. Parametric study on responses of a self-anchored suspension bridge to sudden breakage of a hanger.

    Science.gov (United States)

    Qiu, Wenliang; Jiang, Meng; Huang, Cailiang

    2014-01-01

    The girder of self-anchored suspension bridge is subjected to large compression force applied by main cables. So, serious damage of the girder due to breakage of hangers may cause the collapse of the whole bridge. With the time increasing, the hangers may break suddenly for their resistance capacities decrease due to corrosion. Using nonlinear static and dynamic analysis methods and adopting 3D finite element model, the responses of an actual self-anchored suspension bridge to sudden breakage of hangers are studied in this paper. The results show that the sudden breakage of a hanger causes violent vibration and large changes in internal forces of the bridge. In the process of the vibration, the maximum tension of hanger produced by breakage of a hanger exceeds 2.22 times its initial value, and the reaction forces of the bearings increase by more than 1.86 times the tension of the broken hanger. Based on the actual bridge, the influences of some factors including flexural stiffness of girder, torsion stiffness of girder, flexural stiffness of main cable, weight of girder, weight of main cable, span to sag ratio of main cable, distance of hangers, span length, and breakage time of hanger on the dynamic responses are studied in detail, and the influencing extent of the factors is presented.

  19. Evaluating the time-dependent and bond characteristics of lightweight concrete mixes for Kansas prestressed concrete bridges : technical summary.

    Science.gov (United States)

    2011-07-01

    The majority of the bridges in Kansas are in rural areas. Many of these are : becoming structurally deficient, and are in need of replacement. Due to the location of : these bridges, cost of transporting prestressed girders to these areas often makes...

  20. STUDY, EVALUATION AND TEST OF SUBMODULE TO GIRDER BOLTED JOINT

    CERN Document Server

    Blocki, J; Miralles, Ll; Topilin, N D

    2000-01-01

    The object of the present work is to study the bolted joint submodule to girder. This joint is critical from the point of view of the mechanical integrity of the Tilecal Barrel and Extended Barrel modules and LAr Endcaps. Theoretical analysis, FEM calculations and tests have been carried out in order to find a solution that fulfils the safety factors design criteria.

  1. Discrete vortex method simulations of aerodynamic admittance in bridge aerodynamics

    DEFF Research Database (Denmark)

    Rasmussen, Johannes Tophøj; Hejlesen, Mads Mølholm; Larsen, Allan

    , and to determine aerodynamic forces and the corresponding flutter limit. A simulation of the three-dimensional bridge responseto turbulent wind is carried out by quasi steady theory by modelling the bridge girder as a line like structure [2], applying the aerodynamic load coefficients found from the current version......The meshless and remeshed Discrete Vortex Method (DVM) has been widely used in academia and by the industry to model two-dimensional flow around bluff bodies. The implementation “DVMFLOW” [1] is used by the bridge design company COWI to determine and visualise the flow field around bridge sections...

  2. A Review on Strengthening Steel Beams Using FRP under Fatigue

    Directory of Open Access Journals (Sweden)

    Mohamed Kamruzzaman

    2014-01-01

    Full Text Available In recent decades, the application of fibre-reinforced polymer (FRP composites for strengthening structural elements has become an efficient option to meet the increased cyclic loads or repair due to corrosion or fatigue cracking. Hence, the objective of this study is to explore the existing FRP reinforcing techniques to care for fatigue damaged structural steel elements. This study covers the surface treatment techniques, adhesive curing, and support conditions under cyclic loading including fatigue performance, crack propagation, and failure modes with finite element (FE simulation of the steel bridge girders and structural elements. FRP strengthening composites delay initial cracking, reduce the crack growth rate, extend the fatigue life, and decrease the stiffness decay with residual deflection. Prestressed carbon fibre-reinforced polymer (CFRP is the best strengthening option. End anchorage prevents debonding of the CRRP strips at the beam ends by reducing the local interfacial shear and peel stresses. Hybrid-joint, nanoadhesive, and carbon-flex can also be attractive for strengthening systems.

  3. A review on strengthening steel beams using FRP under fatigue.

    Science.gov (United States)

    Kamruzzaman, Mohamed; Jumaat, Mohd Zamin; Sulong, N H Ramli; Islam, A B M Saiful

    2014-01-01

    In recent decades, the application of fibre-reinforced polymer (FRP) composites for strengthening structural elements has become an efficient option to meet the increased cyclic loads or repair due to corrosion or fatigue cracking. Hence, the objective of this study is to explore the existing FRP reinforcing techniques to care for fatigue damaged structural steel elements. This study covers the surface treatment techniques, adhesive curing, and support conditions under cyclic loading including fatigue performance, crack propagation, and failure modes with finite element (FE) simulation of the steel bridge girders and structural elements. FRP strengthening composites delay initial cracking, reduce the crack growth rate, extend the fatigue life, and decrease the stiffness decay with residual deflection. Prestressed carbon fibre-reinforced polymer (CFRP) is the best strengthening option. End anchorage prevents debonding of the CRRP strips at the beam ends by reducing the local interfacial shear and peel stresses. Hybrid-joint, nanoadhesive, and carbon-flex can also be attractive for strengthening systems.

  4. A Review on Strengthening Steel Beams Using FRP under Fatigue

    Science.gov (United States)

    Jumaat, Mohd Zamin; Ramli Sulong, N. H.

    2014-01-01

    In recent decades, the application of fibre-reinforced polymer (FRP) composites for strengthening structural elements has become an efficient option to meet the increased cyclic loads or repair due to corrosion or fatigue cracking. Hence, the objective of this study is to explore the existing FRP reinforcing techniques to care for fatigue damaged structural steel elements. This study covers the surface treatment techniques, adhesive curing, and support conditions under cyclic loading including fatigue performance, crack propagation, and failure modes with finite element (FE) simulation of the steel bridge girders and structural elements. FRP strengthening composites delay initial cracking, reduce the crack growth rate, extend the fatigue life, and decrease the stiffness decay with residual deflection. Prestressed carbon fibre-reinforced polymer (CFRP) is the best strengthening option. End anchorage prevents debonding of the CRRP strips at the beam ends by reducing the local interfacial shear and peel stresses. Hybrid-joint, nanoadhesive, and carbon-flex can also be attractive for strengthening systems. PMID:25243221

  5. Critical traffic loading for the design of prestressed concrete bridge

    International Nuclear Information System (INIS)

    Hassan, M.I.U.

    2009-01-01

    A study has been carried out to determine critical traffic loadings for the design of bridge superstructures. The prestressed concrete girder bridge already constructed in Lahore is selected for the analysis as an example. Standard traffic loadings according to AASHTO (American Association of State Highway and Transportation Officials) and Pakistan Highway Standards are used for this purpose. These include (1) HL-93 Truck, (2) Lane and (3) Tandem Loadings in addition to (4) Military tank loading, (5) Class-A, (6) Class-B and (7) Class-AA loading, (8) NLC (National Logistic Cell) and (9) Volvo truck loadings. Bridge superstructure including transom beam is analyzed Using ASD and LRFD (Load and Resistance Factor Design) provisions of AASHTO specifications. For the analysis, two longer and shorter spans are selected. This includes the analysis of bridge deck; interior and exterior girder; a typical transom beam and a pier. Dead and live loading determination is carried out using both computer aided and manual calculations. Evaluation of traffic loadings is done for all the bridge components to find out the critical loading. HL-93 loading comes out to be the most critical loading and where this loading is not critical in case of bridge decks; a factor of 1.15 is introduced to make it equivalent with HL-93 -Ioading. SAP-2000 (Structural Engineering Services of Pakistan) and MS-Excel is employed for analysis of bridge superstructure subjected to this loading. Internal forces are obtained for the structural elements of the bridge for all traffic loadings mentioned. It is concluded that HL-93 loading can be used for the design of prestressed concrete girder bridge. Bridge design authorities like NHA (National Highway Authority) and different cities development authorities are using different standard traffic loadings. A number of suggestions are made from the results of the research work related to traffic loadings and method of design. These recommendations may be

  6. Design and construction of PC cable-stayed bridge reducing the weight of dead load (Minamitabaru No. 1 Bridge). Shuko danmen no keiryoka wo hakatta PC shachokyo (kasho Minamitabaru 1 go kyo)

    Energy Technology Data Exchange (ETDEWEB)

    Otsuka, H. (Building Research Inst., Tokyo (Japan)); Ikari, K.; Ono, Y. (Ministry of Construction, Tokyo (Japan)); Hirano, A.

    1993-03-15

    The Minamitabaru No.1 bridge is a PC cable-stayed bridge with a 170m center span. The cross section dead load weight of the main beam in the center span is reduced to decrease the unbalance moment during construction and the negative reaction force after the completion. As a result, the average volume of concrete in the center span becomes 0.55m[sup 3]/m[sup 2] which is less by about 20% in comparison with a PC cable-stayed bridge of the similar scale. Separated 2 chamber box girder cross section is adopted for the shape of the main beam cross section to reduce the dead load weight of the cross section, and to improve the rigidity of the cross section and wind resisting stability, etc. In addition, a cross beam is provided in the diagonal member anchorage position to integrate the two box beams. A wind tunnel test is performed using a 1/30 scale model to confirm the wind resisting stability. The diagonal member is structured with several PC steel members. At the same time, a stretching work carriage is developed and used which can establish 3 dimensional position and direction by a hydraulic jack. 7 figs.

  7. Design and construction of superstructure in prestressed concrete cable-stayed bridge. ; Aomori Bay Bridge. PC shachokyo jobuko no sekkei to seko. ; Aomori Bay Bridge

    Energy Technology Data Exchange (ETDEWEB)

    Ishibashi, T.; Fujimori, S.; Oba, M.; Tsuyoshi, T. (East Japan Railway Co., Tokyo (Japan))

    1991-12-01

    Aomori Bay Bridge is a 1,219m long elevated bridge, a part of No.2 Bay Highway of 1,993m in total length crossing over Aomori railway station which was planned in ordecr to integrate the port facilities of Aomori Harbor and expedite cargo traffic smoothly. Of this Bay Bridge, its main bridge portion crossing over Aomori railway station and the sea area was planned as a continuous prestressed concrete cable-stayed bridge of 498m in total length and consisting of three portions including the central portion in which the main span between the central bridge piers was 240m. It is scheduled to open in the summer of 1992. With regard to the design of this bridge, special care for the view of the bridge has been taken covering from the structure style to the accessories. For this bridge, a large scale underground continuous wall solid base with a box-shaped section consisting of 6 chambers was adopted for the base of a main tower. It has the cantilever suspension structure of the wide girder with the inverted Y-shaped pylons. For its stav cable, was adopted a large capacity stay cable with standard tensile strength of 1,942 fabricated on the site and for its covering tube, a FRP tube was adopted. In this article, the construction of the main girder and stay cables, and the construction control during their installation by projection are reported. 7 refs., 14 figs., 9 tabs.

  8. Covered Bridge Security Manual

    Science.gov (United States)

    Brett Phares; Terry Wipf; Ryan Sievers; Travis Hosteng

    2013-01-01

    The design, construction, and use of covered timber bridges is all but a lost art in these days of pre-stressed concrete, high-performance steel, and the significant growth both in the volume and size of vehicles. Furthermore, many of the existing covered timber bridges are preserved only because of their status on the National Registry of Historic Places or the...

  9. Assessing Static Performance of the Dashengguan Yangtze Bridge by Monitoring the Correlation between Temperature Field and Its Static Strains

    Directory of Open Access Journals (Sweden)

    Gao-Xin Wang

    2015-01-01

    Full Text Available Taking advantage of the structural health monitoring system installed on the steel truss arch girder of Dashengguan Yangtze Bridge, the temperature field data and static strain data are collected and analyzed for the static performance assessment of the bridge. Through analysis, it is found that the static strain changes are mainly caused by temperature field (temperature and temperature difference and train. After the train-induced static strains are removed, the correlation between the remaining static strains and the temperature field shows apparent linear characteristics, which can be mathematically modeled for the description of static performance. Therefore, multivariate linear regression function combined with principal component analysis is introduced to mathematically model the correlation. Furthermore, the residual static strains of mathematical model are adopted as assessment indicator and three kinds of degradation regulations of static performance are obtained after simulation of the residual static strains. Finally, it is concluded that the static performance of Dashengguan Yangtze Bridge was in a good condition during that period.

  10. Analysis of structural diseases in widened structure due to the shrinkage and creep difference of new bridge

    Science.gov (United States)

    Wu, Wenqing; Zhang, Hui

    2018-03-01

    In order to investigate the possible structural diseases brought to the top flange of existing prestressed concrete box girder bridge due to the shrinkage and creep difference between new and old bridge, the stress state of the existing box girder before and after widening and the mechanisms of potential structural diseases were analyzed using finite element method in this paper. Results showed that the inner flange of the old box girder were generally in the state of large tensile stress, the main reason for which was the shrinkage and creep effect difference of the new and old bridge. And the tensile stress was larger than tensile strength of C50 concrete, which would most likely cause crack in the deck plate of box girder. Hence, reinforcement measures are needed to be designed carefully. Meanwhile, the transverse deformation of widened structure had exceeded the distance between the anti-seismic block and the web of box girder at the end cross section, which would squeeze anti-seismic block severely. Therefore, it is necessary to limit the length of continuous bridge in need of widening.

  11. Construction of Daiichi Tamagawa bridge; Daiichi Tamagawa kyoryo no seko

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, O.; Tsuyoshi, T. [East Japan Railway Company, Tokyo (Japan); Ota, T.; Sato, S. [Tekken Corp., Tokyo (Japan)

    1997-05-30

    This paper describes the construction of Daiichi Tamagawa Bridge for JR Tazawako Line, which was reconstructed with the Akita Shinkansen Project apart from the existing line. This bridge is a three-span continuous PC cable stayed bridge. To avoid operation accidents due to snow and ice, independent two-column type with a height of 11 m without beam was employed for the main tower. For the construction of upper part, overhang election construction method was adopted, which can be applied all the year round. The main girder has a single box cross section, and a width of 5.5 m and a beam height of 2.3 m. This was also constructed by the overhang construction method. To reduce the construction period, the main tower was constructed by the precast block construction method. The whole bridge was divided into six blocks by considering the hoist performance of cranes. Reinforcement against bearing pressure and cleavage due to the cable tensile force was conducted by adopting saddle structure for the main tower. Oblique members were jointed with the main girder using lateral beams projected from lateral side of girder. Totally seven PC cables were used for each oblique member. Measurements and management during the overhang construction were also described. The construction was over without problems in August, 1996. This bridge is under test operation using test run vehicles. 2 refs., 20 figs., 7 tabs.

  12. Evaluation of post-tensioning of a curved continuous girder using long-gauge fiber optic sensors

    Science.gov (United States)

    Abdel-Jaber, Hiba; Glisic, Branko

    2014-03-01

    Streicker Bridge is a pedestrian bridge on the Princeton University campus. It consists of a main span and four curved continuous girders (legs). The main span and the southeast leg of the bridge are equipped with fiber optic strain and temperature sensors, allowing the bridge to also function as an on-campus laboratory for the Structural Health Monitoring research group. Parallel sensors were embedded at critical cross-sections in the deck prior to the pouring of concrete. The deck of the southeast leg experienced early age cracking within a few days of concrete pouring, which was detected by the strain sensors. Post-tensioning was then performed and it is assumed that it closed off the cracks. Evaluation of post-tensioning forces is complex due to the existence of the cracks, and this paper researches a procedure to estimate the post-tensioning forces at cracked and uncracked locations. The obtained post-tensioning forces were compared to design forces and conclusions regarding the status of post-tensioning were made. This is important as it gives information on the actual health condition and performance of the structure. It also provides information on the safety of the structure. The objective of this paper is to present a methodology for the evaluation of the post-tensioning force along the deck based on strain measurements. The monitoring system, results, data analysis method, and conclusions regarding the bridge health condition and performance are presented in this paper.

  13. Design and test of box girder for a large wind turbine blade

    DEFF Research Database (Denmark)

    Nielsen, Per Hørlyk; Tesauro, Angelo; Bitsche, Robert

    This report is covering the structural design and full scale test of a box girder as a part of the project “Demonstration of new blade design using manufacturing process simulations” supported by the EUDP program. A box girder with a predetermined outer geometry was designed using new inventions...... that the manufacturing process could include the new inventions. Subsequently the box girder was transported to the blade test facility at DTU Wind Energy. A series of test was performed with the blade to investigate the behaviour during loading, and finally the girder was loaded to ultimate failure. The report includes...... the description of the test setup, the test and an overview over the results from the test performed on the box girder. During the final test the box girder failed at 58 % of the expected ultimate load. Unfortunately, no definite conclusion could be made concerning the failure mechanism....

  14. Wind tunnel experiments on unstable self-excited vibration of sectional girders

    Science.gov (United States)

    Král, Radomil; Pospíšil, Stanislav; Náprstek, Jiří

    2014-01-01

    In this paper, a wind tunnel analysis of two degrees-of-freedom system represented by sectional girders is carried out. Besides an evaluation of the aeroelastic coefficients, the analysis is focused on the influence of the natural frequency ratio on the initiation of unstable vibration, which can be of practical interest. On the phenomenological level, the paper also discusses experimentally ascertained response regimes, with an emphasis on their stability character. The attention is paid to the memory effect in the response described by the hysteresis loop together with the separation curves determining the stability boundaries. The influence of initial disturbance on the stability is examined. Two types of cross-sections were investigated: (i) rectangular one with the aspect ratio 1:5, and (ii) bridge-like cross-section with comparable principal dimensions. For both types of cross-sections, the limits of the stability are significantly affected by an intentionally introduced initial disturbance. This holds especially with regard to the rectangular profile where the separation curves create very narrow sub-domains between a stable and an unstable response, while the bridge-like cross-section demonstrates much stable behaviour.

  15. Large scale testing of nitinol shape memory alloy devices for retrofitting of bridges

    International Nuclear Information System (INIS)

    Johnson, Rita; Emmanuel Maragakis, M; Saiid Saiidi, M; Padgett, Jamie E; DesRoches, Reginald

    2008-01-01

    A large scale testing program was conducted to determine the effects of shape memory alloy (SMA) restrainer cables on the seismic performance of in-span hinges of a representative multiple-frame concrete box girder bridge subjected to earthquake excitations. Another objective of the study was to compare the performance of SMA restrainers to that of traditional steel restrainers as restraining devices for reducing hinge displacement and the likelihood of collapse during earthquakes. The results of the tests show that SMA restrainers performed very well as restraining devices. The forces in the SMA and steel restrainers were comparable. However, the SMA restrainer cables had minimal residual strain after repeated loading and exhibited the ability to undergo many cycles with little strength and stiffness degradation. In addition, the hysteretic damping that was observed in the larger ground accelerations demonstrated the ability of the materials to dissipate energy. An analytical study was conducted to assess the anticipated seismic response of the test setup and evaluate the accuracy of the analytical model. The results of the analytical simulation illustrate that the analytical model was able to match the responses from the experimental tests, including peak stresses, strains, forces, and hinge openings

  16. Dynamic and Static Behavior of Hollow-Core FRP-Concrete-Steel and Reinforced Concrete Bridge Columns under Vehicle Collision

    Directory of Open Access Journals (Sweden)

    Omar I. Abdelkarim

    2016-12-01

    Full Text Available This paper presents the difference in behavior between hollow-core fiber reinforced polymer-concrete-steel (HC-FCS columns and conventional reinforced concrete (RC columns under vehicle collision in terms of dynamic and static forces. The HC-FCS column consisted of an outer FRP tube, an inner steel tube, and a concrete shell sandwiched between the two tubes. The steel tube was hollow inside and embedded into the concrete footing with a length of 1.5 times the tube diameter while the FRP tube stopped at the top of footing. The RC column had a solid cross-section. The study was conducted through extensive finite element impact analyses using LS-DYNA software. Nine parameters were studied including the concrete material model, unconfined concrete compressive strength, material strain rate, column height-to-diameter ratio, column diameter, column top boundary condition, axial load level, vehicle velocity, and vehicle mass. Generally, the HC-FCS columns had lower dynamic forces and higher static forces than the RC columns when changing the values of the different parameters. During vehicle collision with either the RC or the HC-FCS columns, the imposed dynamic forces and their equivalent static forces were affected mainly by the vehicle velocity and vehicle mass.

  17. Onboard monitoring of fatigue damage rates in the hull girder

    DEFF Research Database (Denmark)

    Nielsen, Ulrik Dam; Jensen, Jørgen Juncher; Pedersen, Preben Terndrup

    2011-01-01

    Most new advanced ships have extensive data collection systems to be used for continuous monitoring of engine and hull performance, for voyage performance evaluation etc. Such systems could be expanded to include also procedures for stress monitoring and for decision support, where the most...... critical wave-induced ship extreme responses and fatigue damage accumulation can be estimated for hypothetical changes in ship course and speed in the automatically estimated wave environment.The aim of this paper is to outline a calculation procedure for fatigue damage rate prediction in hull girders...... taking into account whipping stresses. It is conceptually shown how such a method, which integrates onboard estimation of sea states, can be used to deduce decision support with respect to the accumulated fatigue damage in the hull girder.The paper firstly presents a set of measured full-scale wave...

  18. Strength Enhancement of Prestressed Concrete Dapped-End Girders

    Directory of Open Access Journals (Sweden)

    Shatha Dhia Mohammed

    2015-10-01

    Full Text Available This paper presents the application of nonlinear finite element models in the analysis of dapped-ends pre-stressed reinforced concrete girders under static loading by using ANSYS software. The girder dimensions are (4.90 m span, 0.40 m depth, 0.20 m width, 0.20 m nib depth, and 0.10 m nib length and the parameters considered in this research are the pre-stress effect, and strand profile (straight and draped. The numerical results are compared with the experimental results of the same girders. The comparisons are carried out in terms of initial prestress effect, load- deflection curve, and failure load. Good agreement was obtained between the analytical and experimental results. Even that, the numerical model was stiffer than the experimental, but; there were a good agreements in both trends and values. The difference varies in the range (5-12% for the deflection. Results have shown that the pre-stress force has increased the static ultimate load capacity by (35% in case of straight strand and by (97% in case of draped strand

  19. On the Influence of Hull Girder Flexibility on the Wave

    DEFF Research Database (Denmark)

    Seng, Sopheak; Andersen, Ingrid Marie Vincent; Jensen, Jørgen Juncher

    2012-01-01

    Numerical predictions and model test results of the wave induced bending moments in a 9,400 TEU post-Panamax container vessel are presented for two regular wave scenarios. Different numerical procedures have been applied: a linear and non-linear time-domain strip theory and a direct calculation (...... (CFD) solving the Navier-Stokes equations with the free surface captured by a volume-of-fluid (VOF) method. In all procedures the flexibility of the hull girder is modelled as a non-uniform Timoshenko beam. It is observed that the non-linear models agree well with the model tests...... and as there is no occurrence of severe slamming in the cases considered, the inexpensive non-linear strip theory is as accurate as the direct CFD calculation method. In a comparison with the results using the rigid body assumption, the increase in the vertical bending moment (VBM) amidships due to the flexibility of the hull...... girder is found to be approximately 7% (peak-to-peak amplitude) in general. The non-linear responses, however, contain over-harmonic frequencies which may coincide with the natural frequency of the two-node vertical bending mode inducing resonance. In that case the hull girder flexibility causes...

  20. Dynamic response of a typical synchrotron magnet/girder assembly

    International Nuclear Information System (INIS)

    Jendrzejczyk, J.A.; Smith, R.K.; Vogt, M.E.

    1993-06-01

    In the Advanced Photon Source, the synchrotron booster ring accelerates positrons to the required energy level of 7 GeV. The positrons are then injected into the storage ring where they continue to orbit for 10--15 h. The storage ring quadrupoles have very stringent vibration criteria that must be satisfied to ensure that beam emittance growth is within acceptable limits, viz., <10%. Because the synchrotron booster ring is not operated after particle insertion into the storage ring, its vibration response is not a critical issue relative to the performance of the storage ring beam. Nevertheless, the synchrotron pulses at a frequency of 2 Hz, and if a vibration response frequency of the synchrotron magnet/girder assembly were to coincide with the pulsation frequency or its near harmonics, large-amplitude motion could result, with the effect that it could compromise the operation of the synchrotron. Due to the complex dynamics of the synchrotron magnet/girder assembly, it is necessary to measure the dynamic response of a prototypic assembly and its components to ensure that the inherent dynamic response frequencies are not equal to 2 Hz or any near harmonics. Dynamic-response measurement of the synchrotron girder assembly and component magnets is the subject of this report

  1. Mössbauer characterization of the corrossion products of steels in civil works: Suspension bridge and reinforced concrete

    Science.gov (United States)

    Kounde, B.; Raharinaivo, A.; Olowe, A. A.; Rezel, D.; Bauer, Ph.; Génin, J. M. R.

    1989-03-01

    The rusting condition of the cables of suspension bridges is usually evaluated by self-induction measurements. This method assumes that rusts of same chemical composition have always the same magnetic properties. Unfortunately in some cases, this assumption has shown to be questionable and this study has demonstrated that Mössbauer spectroscopy supplies additional information on the nature of some detected defects. In the case of reinforced concrete, it has been empirically pointed out that the content of agressive element, e.g. Cl- ions, should be under a trigger. Mössbauer studies have demonstrated the physical meaning of this practical rule.

  2. Study on the selection of steel or prestressed concrete cable stayed bridge by using diaggregate behavioral model; Hishukei rojitto model wo mochiita koshachokyo to PC shachokyo no kyoshiki sentaku ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Araki, Y.; Furuta, H.; Maeda, E.; Furukawa, K. [Yamaguchi University, Yamaguchi (Japan). Faculty of Engineering

    1994-09-15

    A discussion was given to make clear the selection factors in selecting bridge types (steel cable stayed bridge and prestressed concrete cable stayed bridge). The discussion is intended to consider the future development of both bridges. Quoting a cable stayed bridge with a span length of 250 m that can be selected from either bridge, an evaluation was made by using calculations that uses the disaggregate behavioral model theory based on questionnaire responses from engineers. The analysis uses the following procedure: utility function values of the two term behavioral model (having two choices) are specified and the characteristics variables are selected; the data are prepared according to the specifications, which are used to estimate parameters by a maximum likelihood estimation method; and estimation amount is estimated by using the covariance matrix, which is given a `t` value verification. The conclusions: what gives the large effect to the selection is the engineering capacity and sociality; the result contains vocational consciousness; the economy is measured by the large weight of construction cost for the upper part structures and cost required for large repairs; materials affect largely the reliability, and so does the technological level the constructibility; the comprehensive technical capability, freedom in design and the experience attained by Japan have great effects in terms of technological capability. 10 refs., 10 figs., 11 tabs.

  3. Investigation of Ultimate Strength of Composite Open-Web Joist-Girders

    OpenAIRE

    Showalter, Sheldon Lee

    1999-01-01

    The goal of this research was to study several methods of generating composite action using open-web joist-girders, designed and manufactured by Nucor Corporation. In addition to comparing the relative performance of these systems, it was intended to determine whether the current accepted design procedure for composite joists could be extended to joist-girders.

  4. Behavior of Reinforced Concrete Hybrid Trapezoidal Box Girders Using Ordinary and Highly Strength Concrete

    Directory of Open Access Journals (Sweden)

    Nameer A. Alawsh

    2018-03-01

    Full Text Available In this paper, the general behavior of reinforced concrete hybrid box girders is studied by experimental and numerical investigation. Experimental work is included casting monolithically five specimens of box girders with trapezoidal cross section and testing it as simply supported under two point loading. Two specimens were cast as homogenous box girders (full normal strength concrete (NSC (about 35 MPa and full high strength concrete (HSC (about 55 MPa and three specimens were cast as hybrid box girders (HSC in upper flange only, HSC in upper flange and half depth of webs, and HSC in bottom flange and total depth of webs. Experimental results showed significant effects of concrete hybridization on the structural behavior of box girders specimens such as: cracking loads, cracking patterns, ultimate strengths, and failure modes. The ultimate strength of Hybrid box girders increased by 23% as average when compared with the homogenous box girder (full NSC and decreased by 9% as average when compared with homogenous box girder (full HSC. In numerical investigation, the tested specimens were modeled and analyzed using three dimensional non-linear finite element analysis. The analysis was carried out by using a computer program (ANSYS V16.1. The numerical results showed an acceptable agreement with the experimental work with difference about (3.12% and 9.588% as average for ultimate load and deflection, respectively.

  5. Design and test of box girder for a large wind turbine blade

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Per H.; Tesauro, A.; Bitsche, R. [Technical Univ. of Denmark. DTU Wind Energy, DTU Risoe Campus, Roskilde (Denmark)] [and others

    2012-09-15

    This report is covering the structural design and full scale test of a box girder as a part of the project ''Demonstration of new blade design using manufacturing process simulations'' supported by the EUDP program. A box girder with a predetermined outer geometry was designed using new inventions, which create an inner structure in the box girder. With a combination of advanced FEM analysis and the inventions it was possible to reduce the material thickness of the cap by up to 40%. The new design of the box girder was manufactured at SSP Technology A/S, where it was demonstrated that the manufacturing process could include the new inventions. Subsequently the box girder was transported to the blade test facility at DTU Wind Energy. A series of test was performed with the blade to investigate the behaviour during loading, and finally the girder was loaded to ultimate failure. The report includes the description of the test setup, the test and an overview over the results from the test performed on the box girder. During the final test the box girder failed at 58 % of the expected ultimate load. Unfortunately, no definite conclusion could be made concerning the failure mechanism. (Author)

  6. Low Cost Wireless Fatigue Crack Monitoring System Using RFID Arrays

    Science.gov (United States)

    2018-03-23

    The use of welded steel cover plates had been a common design practice to increase beam section capacity in regions ofhigh torsion for decades. Many steel girder bridges with cover plates are still in service. Steel girder bridges are subject to cycl...

  7. Evaluation of Fatigue Strength Improvement by CFRP Laminates and Shot Peening onto the Tension Flanges Joining Corrugated SteelWebs

    Directory of Open Access Journals (Sweden)

    Zhi-Yu Wang

    2015-08-01

    Full Text Available Corrugated steel web with inherent high out-of-plane stiffness has a promising application in configuring large span highway bridge girders. Due to the irregularity of the configuration details, the local stress concentration poses a major fatigue problem for the welded flange plates of high strength low alloy structural steels. In this work, the methods of applying CFRP laminate and shot peening onto the surfaces of the tension flanges were employed with the purpose of improving the fatigue strength of such configuration details. The effectiveness of this method in the improvement of fatigue strength has been examined experimentally. Test results show that the shot peening significantly increases hardness and roughness in contrast to these without treatment. Also, it has beneficial effects on the fatigue strength enhancement when compared against the test data of the joints with CFRP strengthening. The stiffness degradation during the loading progress is compared with each treatment. Incorporating the stress acting on the constituent parts of the CFRP laminates, a discussion is made regarding the mechanism of the retrofit and related influencing factors such as corrosion and economic cost. This work could enhance the understanding of the CFRP and shot peening in repairing such welded details and shed light on the reinforcement design of welded joints between corrugated steel webs and flange plates.

  8. Experiments and theory on deck and girder crushing

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup; Ocakli, Hasan

    1999-01-01

    -deflection curves and modes of deformation for decks, stringer decks and deep thin-walled beams subjected to central or excentric point loads between transverse frames. Based on theory and experiments, various modelling aspects of the local/global failure of the beams are discussed. The agreement between......This paper is concerned with theoretical and experimental analysis of deep plastic collapse of a deck or deep girder subjected to an in-plane, concentrated load. A theory is derived which is valid until initition of fracture in the structure. The presented experimental results show load...

  9. Structural health monitoring of the Gröndals Bridge in Sweden: the behaviour of CFRP strengthening in cold temperature

    Science.gov (United States)

    Hejll, Arvid; Täljsten, Björn; Carolin, Anders

    2006-03-01

    To obtain a better knowledge of existing structures behaviour monitoring can be used. The use of monitoring in bridge structures by the use of instruments to assess the integrity of structures is not new and there are reports from structures tested as early as in the 19th century according to ISIS Canada1 However, the term SHM (Structural Health Monitoring) is relatively new to civil engineering and the driving force to implement SHM comes from recognising the limitations of conventional visual inspections and evaluations using conservative codes of practice. The possibilities to monitor existing structures with help of the rapidly evolving Information Technology are to day carried out. The objective of SHM is to monitor the in-situ behaviour of a structure accurately and efficiently, to assess its performance under various service conditions, to detect damage or deterioration, and to determine the health or condition of the structure1. In Sweden strengthening and periodic monitoring of a large freivorbau bridge (pre-stresed concrete box girder bridge) has been carried out, the Gröndals Bridge. The bridge is located in Stockholm and is approximately 400 m in length with a free span of 120 m. It was opened to tram traffic in year 2000. Just after opening cracks were noticed in the webs, these cracks have then increased, the size of the largest cracks exceeded 0.5 mm, and at the end of year 2001 the bridge was temporarily strengthened. This was carried out with externally placed prestressed steel stays. The reason for cracking is quite clear but the responsibility is still debated. Nevertheless, it was evidently that the bridge needed to be strengthened. The strengthening methods used were CFRP plates in the Service Limit State (SLS) and prestressed dywidag stays in the Ultimate Limit State (ULS). The strengthening was carried out during year 2002. At the same time monitoring of the bridge commenced, using LVDT crack gauges as well as optical fibre sensors. This

  10. Linear Cracking in Bridge Decks

    Science.gov (United States)

    2018-03-01

    Concrete cracking in bridge decks remains an important issue relative to deck durability. Cracks can allow increased penetration of chlorides, which can result in premature corrosion of the reinforcing steel and subsequent spalling of the concrete de...

  11. Myocardial Bridge

    Science.gov (United States)

    ... Center > Myocardial Bridge Menu Topics Topics FAQs Myocardial Bridge En español Your heart is made of muscle, ... surface of the heart. What is a myocardial bridge? A myocardial bridge is a band of heart ...

  12. Design Optimization of Hybrid FRP/RC Bridge

    Science.gov (United States)

    Papapetrou, Vasileios S.; Tamijani, Ali Y.; Brown, Jeff; Kim, Daewon

    2018-04-01

    The hybrid bridge consists of a Reinforced Concrete (RC) slab supported by U-shaped Fiber Reinforced Polymer (FRP) girders. Previous studies on similar hybrid bridges constructed in the United States and Europe seem to substantiate these hybrid designs for lightweight, high strength, and durable highway bridge construction. In the current study, computational and optimization analyses were carried out to investigate six composite material systems consisting of E-glass and carbon fibers. Optimization constraints are determined by stress, deflection and manufacturing requirements. Finite Element Analysis (FEA) and optimization software were utilized, and a framework was developed to run the complete analyses in an automated fashion. Prior to that, FEA validation of previous studies on similar U-shaped FRP girders that were constructed in Poland and Texas is presented. A finer optimization analysis is performed for the case of the Texas hybrid bridge. The optimization outcome of the hybrid FRP/RC bridge shows the appropriate composite material selection and cross-section geometry that satisfies all the applicable Limit States (LS) and, at the same time, results in the lightest design. Critical limit states show that shear stress criteria determine the optimum design for bridge spans less than 15.24 m and deflection criteria controls for longer spans. Increased side wall thickness can reduce maximum observed shear stresses, but leads to a high weight penalty. A taller cross-section and a thicker girder base can efficiently lower the observed deflections and normal stresses. Finally, substantial weight savings can be achieved by the optimization framework if base and side-wall thickness are treated as independent variables.

  13. An influence of technological contraflexure of crane bridges on its durability

    Directory of Open Access Journals (Sweden)

    Artur BLUM

    2010-01-01

    Full Text Available Standard requirements till 1996 year during bridge crane manufacturing demanded a positive technological contraflexure. As a result of this process were implemented technological compressive stress into tensile zone from inertial and operational loads and tensile stress into compressive zone. This way there were redistributed resultant stress which have increased fatigue strength of exploited crane bridges. Actually valid standard PN-ISO 7363 has removed this obligatory requirement. Its use depends of crane buyer demands. Reduction of initial positive deflection can be seen after few years of crane operations. It is a case of girders permanent deflections increment. Article presents method of technological prestressing of bridge girders with its practical application to obtain positive contrafexure.

  14. Investigation of aerodynamic stability by wind response observation during cantilever construction of the Ikara Ohashi bridge; Ikara Ohashi haridashi sekoji no kaze kansoku ni yoru taifu anteisei no kento

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, K.; Mukai, H.; Takeda, T. [Kajima Corp., Tokyo (Japan)

    1995-12-20

    In order to ensure aerodynamic stability during cantilever construction of the Ikara Ohashi Bridge, wind response observation was carried out and discussions were given on the result. The Ikara Ohashi Bridge is a 5-span continuous PC cable-stayed bridge with the central span being a concrete bridge having a length of 260 m, which is the longest in Japan. The bridge was constructed using a method that main girders are extended from the central tower to the right and left sides while the girders are stayed by bracing cables. The bridge construction site is in an area which is often subjected to typhoons and gusts like seasonal winds in winter, hence a discussion on aerodynamic stability of the bridge especially during extension work was viewed as an important matter. In addition, the construction used two small-capacity cables spaced and bundled as the bracing material, which required verification on their aerodynamic stability. In order to identify vibration characteristics of the main girders and the central tower, wind response observation has been performed as soon as the construction was begun. As a result, the vibration characteristics of the main girders and the central tower were identified, and it was verified that vibration shape and dominant frequency can be evaluated properly by an intrinsic value analysis that uses a multi-material point frame model. Furthermore, effects of different vibration absorbing measures were compared, and the effective methods were adopted as the result. 4 refs., 12 figs.

  15. Computer modeling of road bridge for simulation moving load

    Directory of Open Access Journals (Sweden)

    Miličić Ilija M.

    2016-01-01

    Full Text Available In this paper is shown computational modelling one span road structures truss bridge with the roadway on the upper belt of. Calculation models were treated as planar and spatial girders made up of 1D finite elements with applications for CAA: Tower and Bridge Designer 2016 (2nd Edition. The conducted computer simulations results are obtained for each comparison of the impact of moving load according to the recommendations of the two standards SRPS and AASHATO. Therefore, it is a variant of the bridge structure modeling application that provides Bridge Designer 2016 (2nd Edition identical modeled in an environment of Tower. As important information for the selection of a computer applications point out that the application Bridge Designer 2016 (2nd Edition we arent unable to treat the impacts moving load model under national standard - V600. .

  16. Hybrid Bridge Structures Made of Frp Composite and Concrete

    Science.gov (United States)

    Rajchel, Mateusz; Siwowski, Tomasz

    2017-09-01

    Despite many advantages over the conventional construction materials, the contemporary development of FRP composites in bridge engineering is limited due to high initial cost, low stiffness (in case of glass fibers) and sudden composite failure mode. In order to reduce the given limitations, mixed (hybrid) solutions connecting the FRP composites and conventional construction materials, including concrete, have been tested in many countries for 20 years. Shaping the hybrid structures based on the attributes of particular materials, aims to increase stiffness and reduce cost without losing the carrying capacity, lightness and easiness of bridges that includes such hybrid girders, and to avoid the sudden dangerous failure mode. In the following article, the authors described examples of hybrid road bridges made of FRP composite and concrete within the time of 20 years and presented the first Polish hybrid FRP-concrete road bridge. Also, the directions of further research, necessary to spread these innovative, advanced and sustainable bridge structures were indicated.

  17. Development of a new-type super-long bridge; Chochotaikyo ni tekigoshita shinkeishiki kyoryo no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, K.; Shimodoio, H.; Saito, T.; Nogami, C.; Oryu, T.; Morikawa, M. [Kawasaki Heavy Industries, Ltd., Kobe (Japan)

    1998-12-20

    In order to realize large strait-crossing projects in the near future, it is necessary to develop a new type of super-long span bridge, which has a superior aerodynamic stability and is cost effective. We have been proposed a new type of suspension bridge using a 2-box and 1-box combined girder to apply to such a project And this time, we propose the cable stayed suspension bridge using a 2- box and 1-box combined girder aiming for improvement of aerodynamic stability with increase of torsional rigidity. This paper describes the performance of this cable stayed suspension bridge obtained from aerodynamic analysis. As a result, it can be confirmed that this newly developed cable stayed suspension system has fine characteristics and shows more potential for economical construction than the early proposed suspension system. (author)

  18. Performance evaluation of concrete bridge decks reinforced with MMFX and SSC rebars.

    Science.gov (United States)

    2006-01-01

    This report investigates the performance of bridge decks reinforced with stainless steel clad (SSC) and micro-composite multistructural formable steel (MMFX) rebars. The two-span Galloway Road Bridge on route CR5218 over North Elkhorn Creek in Scott ...

  19. Optimization of the box-girder of overhead crane with constrained ...

    African Journals Online (AJOL)

    haroun

    Keywords: Overhead crane - Box-girder - New bat algorithm - level of ... much more efficiency and robustness compared to the genetic algorithm (GA) and PSO ...... optimization: developments, applications and resources," in Evolutionary.

  20. A Brillouin smart FRP material and a strain data post processing software for structural health monitoring through laboratory testing and field application on a highway bridge

    Science.gov (United States)

    Bastianini, Filippo; Matta, Fabio; Galati, Nestore; Nanni, Antonio

    2005-05-01

    Strain and temperature sensing obtained through frequency shift evaluation of Brillouin scattered light is a technology that seems extremely promising for Structural Health Monitoring (SHM). Due to the intrinsic distributed sensing capability, Brillouin can measure the deformation of any individual segment of huge lengths of inexpensive single-mode fiber. In addition, Brillouin retains other typical advantages of Fiber Optic Sensors (FOS), such as harsh environment durability and interference rejection. Despite these advantages, the diffusion of Brillouin for SHM is constrained by different factors, such as the high equipment cost, the commercial unavailability of specific SHM oriented fiber products and even some prejudices on the required sensitivity performances. In the present work, a complete SHM pilot application was developed, installed and successfully operated during a diagnostic load test on the High Performance Steel (HPS) bridge A6358 located at the Lake of the Ozarks (Miller County, MO, USA). Four out of five girders were extensively instrumented with a "smart" Glass Fiber Reinforced Polymer (GFRP) tape having embedded fibers for strain sensing and thermal compensation. Data collected during a diagnostic load test were elaborated through a specific post-processing software, and the strain profiles retrieved were compared to traditional strain gauges and theoretical results based on the AASHTO LRFD Bridge Design Specifications for structural assessment purposes. The excellent results obtained confirm the effectiveness of Brillouin SHM systems for the monitoring of real applications.

  1. Comparative life cycle cost assessment of painted and hot-dip galvanized bridges.

    Science.gov (United States)

    Rossi, B; Marquart, S; Rossi, G

    2017-07-15

    The study addresses the life cycle cost assessment (LCCA) of steel bridges, focusing on the maintenance activities and the maintenance scenario. Firstly, the unit costs of maintenance activities and their durability (i.e. the time between two activities) are evaluated. Pragmatic data are provided for the environment category C4 and for three activities: Patch Up, Overcoating and Remove & Replace. A comparative LCCA for a typical hypothetic steel girder bridge is carried out, either painted or hot-dip galvanized (HDG), in the environmental class C4. The LCC versus the cumulated life is provided for both options. The initial cost of the steel unpainted option is only 50.3% of the HDG option. It is shown that after 'Overcoating' occurring at 18.5 years, the total Net Present Value (NPV) of the painted option surpasses that of the HDG option. A sensitivity analysis of the NPV to the cost and service life parameters, the escalation and discount rates is then performed. The discount and escalation rates, considerably influences the total LCC, following a non-linear trend. The total LCC decreases with the discount rate increasing and, conversely, increases with the escalation rate increasing. Secondly, the influence of the maintenance scenario on the total LCC is assessed based on a probabilistic approach. A permutation of the three independent maintenance activities assumed to occur six times over the life of the bridge is considered and a probability of occurrence is associated to each unique scenario. The most probable scenarios are then classified according to their NPV or achieved service life. This approach leads to the definition of a cost-effective maintenance scenario i.e. the scenario, within all the considered permutations, that has the minimum LCC in a range of lifespan. Besides, the probabilistic analysis also shows that, whatever the scenario, the return on investment period ranges between 18.5 years and 24.2 years. After that period, the HDG option becomes

  2. Evaluating the performance of skewed prestressed concrete bridge after strengthening

    Science.gov (United States)

    Naser, Ali Fadhil; Zonglin, Wang

    2013-06-01

    The objectives of this paper are to explain the application of repairing and strengthening methods on the damaged members of the bridge structure, to analyze the static and dynamic structural response under static and dynamic loads after strengthening, and to evaluate the structural performance after application of strengthening method. The repairing and strengthening methods which are used in this study include treatment of the cracks, thickening the web of box girder along the bridge length and adding internal pre-stressing tendons in the thickening web, and construct reinforced concrete cross beams (diaphragms) between two box girders. The results of theoretical analysis of static and dynamic structural responses after strengthening show that the tensile stresses are decreased and become less than the allowable limit values in the codes. The values of vertical deflection are decreased after strengthening. The values of natural frequencies after strengthening are increased, indicating that the strengthening method is effective to reduce the vibration of the bridge structure. Therefore, the strengthening methods are effective to improve the bearing capacity and elastic working state of the bridge structure and to increase the service life of the bridge structure.

  3. Design of Usui bridge (PC cable stayed bridge). Usuihashi (PC shachokyo) no sekkei ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Kido, M.; Iizuka, Y. (Japan Highway Public Corp., Tokyo (Japan)); Tanaka, S.; Otsuka, K. (P.S. Concrete Co. Ltd. Kajima Corp. Joint Venture, Tokyo (Japan)); Kitakuni, S. (Kajima Corp., Tokyo (Japan))

    1991-11-30

    Structure and design of single suspension PC cable bridge, which is first kind of high way bridge in Japan and aiming to start for general use by March, 1993, are reported. As a construction outline, main construction quantity and general layout of the whole bridge together with the selective detail and characteristics of the diagonal member, tower, main girder and tower support member, are cited. Design conditions( load, materials, allowable stress and others ), basic plan of the design, and structure analysis( surface stress framed structure analysis, stereoscopic framework analysis and FEM analysis of local stress ) are explained. Design of structure member like main girder is based on diagonal member tension, wave shearing force, level of diagonal strain stress, bending stress when diagonal member anchors the deformed main tower caused by living load during earth quake, principal stress of main tower junction and local stress etc. Main tower support member design is based on the results of corbel shearing force at varied cross section and main stress, and diagonal member design is decided by allowable stress. Diagonal member anchorage traverse beam design depends on bending moment of traverse beam and shearing force. 3 refs., 15 figs., 1 tab.

  4. Fatigue strength of field welded joints in I-section girders of thick flange plates with cope hole details; Sukarappu wo yusuru atsuita I gata danmen keta genba yosetsu tsugitebu no hiro kyodo

    Energy Technology Data Exchange (ETDEWEB)

    Minami, K.; Miki, C.; Tateishi, K. [Tokyo Institute of Technology, Tokyo (Japan)

    1997-10-15

    Field welding an I-section girder forms details having scallop at the web, whereas the presence of the scallop causes shear deformation and localized stress concentration. Therefore the details in joints with low fatigue strength are ranked as class G in the fatigue design guideline published by JSSC. With special notice on the effect of shear, the present study has varied the phase by using multiple number of jacks; so loaded that the direction of the shear force will change; assumed field welding of a bridge constructed with a few number of main girders; and verified fatigue strength at thick flange plates. In addition, in order to improve the fatigue strength, elucidation was given on the effect of grinder finish at boxing welds. From these results, items to be considered were made clear when structural details are designed and fabricated, in which I-section girders having scallop are welded in fields. Furthermore, it was considered that stress in web plate jointing welding bead becomes relatively higher than local stress in boxing, which was indicated as a point requiring precaution. 8 refs., 20 figs., 2 tabs.

  5. Study and application of micrometric alignment on the prototype girders of the CLIC Two-Beam Module

    CERN Document Server

    Gazis, Nikolaos; Mainaud-Durand, Hélène; Samochkine, Alexandre; Anastasopoulos, Michail

    2011-01-01

    The Compact LInear Collider (CLIC), currently under study at CERN, aims at the development of a Multi-TeV e+ e- collider. The micro-precision CLIC RF-structures will have an accelerating gradient of 100 MV/m and will be mounted and aligned on specially developed supporting girders. The girder fabrication constraints are dictated by stringent physics requirements. The micrometric pre-alignment over several kilometers of girders, allow for the CLIC structures to fulfill their acceleration and collision functionality. Study of such girders and their sophisticated alignment method, is a challenging case involving dedicated mechanical design as well as prototype production and experimental testing.

  6. Numerical investigation of out-of-plane secondary stress in the web of floor beam of steel truss bridge. Ko torasu kyo no yukageta web ni shojiru mengai niji oryoku no suchiteki gen'in bunseki

    Energy Technology Data Exchange (ETDEWEB)

    Sato, T. (Kisarazu National College of Technology, Chiba (Japan)); Kuranishi, S. (Kanto Gakuin Univ., Kanagawa (Japan). Faculty of Engineering); Nakazawa, M. (Tohoku Univ., Sendai (Japan). Faculty of Enginering)

    1994-06-20

    Comparative investigation of numerical analysis results of out-of-plane secondary stress caused in a cross beam web around scallop before reinforcement and around cutting portion of vertical stiffeners after reinforcement was carried out. In case of steel truss bridge, there exists difference in axial thrust between outside stringers which continue through a cross beam, and it was revealed that this axial thrust was the main factor which causes partial bending stress in a cross beam web plate. When the lower end of vertical stiffeners is not connected to a cross beam foot flange considering of welding, out-of-plane secondary stress was caused partially in a cross beam web plate around scallop, because of the difficult to transmit adjoining stringers axial thrust difference directly to foot flange. In case of the actual analysis, cross beam web plate around cutting portion of vertical stiffeners causes partial out-of-plane secondary stress in web plate, due to being pressed partially by comparatively high stiffness vertical stiffeners. When repair and reinforcement of steel road truss bridge are carried out, it is necessary to take close attention specially on the structure of the parts in which outside stringers is connected to cross beam. 18 refs., 16 figs.

  7. Evaluation of High-Speed Railway Bridges Based on a Nondestructive Monitoring System

    Directory of Open Access Journals (Sweden)

    Mosbeh R. Kaloop

    2016-01-01

    Full Text Available Recently, trains’ velocities in Korea increased more than the speed used in the design of some bridges. Accordingly, this paper demonstrates the evaluation of a railway bridge due to high-speed trains’ movement. A nondestructive monitoring system is used to assess the bridge performance under train speeds of 290, 360, 400 and 406 km/h. This system is comprised of a wireless short-term acceleration system and strain monitoring sensors attached to the bridge girder. The results of the analytical methods in time and frequency domains are presented. The following conclusions are obtained: the cross-correlation models for accelerations and strain measurements are effective to predict the performance of the bridge; the static behavior is increased with train speed developments; and the vibration, torsion, fatigue and frequency contents analyses of the bridge show that the bridge is safe under applied trains’ speeds.

  8. Nondestructive testing for bridge diagnosis

    International Nuclear Information System (INIS)

    Oshima, Toshiyuki; Mikami, Shuichi; Yamazaki, Tomoyuki

    1997-01-01

    There are many motivations for bridge diagnosis using Nondestructive testing (NDT) to monitor its integrity. The measured frequency and damping on real bridge are compared in one figure as a function of span length and general aspects are explained. These date were measured in every construction of bridges and applied to design new bridges. Ultrasonic testing is also well used for concrete and steel members mainly to detect internal damages or delaminations. Detail analysis on reflected waves gives us more accurate information about the defect. Experimental results are shown as examples in this paper.

  9. Final Environmental Assessment, Horse Creek Bridge Replacement

    Science.gov (United States)

    2010-10-01

    existing bridge pipes that have failed and replace the failed structure with a new, prefabricated pedestrian bridge within the original bridge footprint...vehicles, nor designed for support of standard passenger vehicle loads. The bridge would be a single prefabricated unit consisting of a steel grate...placed on new concrete abutments built on the existing foundations on the creek banks, and put in place by a crane operating from the vehicle parking

  10. Chichibu park bridge, a Japan's longest PC cable suspension bridge that attaches importance to scenery. Keikan wo jushishita Nippon saidai no PC shachokyo 'Chichibu koenkyo'

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-01

    This paper introduces the feature of Chichibu Park Bridge, a Japan's longest PC cable suspension bridge that attaches importance to scenery. The maximum effective span of Chichibu Park Bridge which is a two-span continuous PC cable suspension bridge measures 195 m, that means the center span length is equivalent to about 400 m if converted to a three-span structure. With respect to the design that values the scenic effect, the main tower has relief engravings of stone carving tone using Chichibu Night Festival as a motif disposed around it; lighting up is applied to the main tower to highlight it so that it can be viewed from far away places; and a balcony is built on the center of the bridge. Chichibu Park Bridge has the bridge axial direction stagger with the river flow direction at 45[degree] to reduce water resistance. The tensile force generated at the corbel section according to the main tower reactive force is dealt with reinforced concrete rather than with prestressed concrete. The main tower adopts a two-chamber girder structure as its cross section shape from the view points of rigidity assurance and scenic effect. For construction control, micro computers are used to correct growing change in bend of the main girder due to temperature change and cable tension change. 6 figs., 4 tabs.

  11. Railroad Bridges

    Data.gov (United States)

    Department of Homeland Security — Bridges-Rail in the United States According to The National Bridge Inspection Standards published in the Code of Federal Regulations (23 CFR 650.3), a bridge isA...

  12. STRESS-DEFORMED STATE OF A STRUT-FRAMED CRANE GIRDER

    Directory of Open Access Journals (Sweden)

    Kh. M. Muselemov

    2017-01-01

    Full Text Available Objectives. The aim of the present work is to study the influence of design parameters on the stress-deformed state of a sprengel crane girder; to compile the tables and corresponding graphs illustrating changes in internal force factors in the characteristic cross-sections of the system elements under consideration. The article describes the study of the stress-deformed state (SDS of a metal strut-framed crane girder.Methods. Numerical methods of analysis based on the use of the Green's function are used during solving this problem. A dimensionless parameter is introduced, depending on which the tables and graphs are constructed. According to the known algorithm, the calculations of internal force factors in the sections of the considered construction are performed.Results. Depending on the dimensionless parameter characterising the geometry and physical features of the system, tables of bending moments and transverse forces are compiled. According to these tables, the appropriate graphs are plotted in order to choose easily the optimal design parameters.Conclusion. The dependence of the moments and transverse forces on the dimensionless parameter k was found, the corresponding graphs were plotted and the metal costs for the girders were calculated. The minimum values of the moments and transverse forces are established to take place when the dimensionless parameter k values are close to zero. The most economical was a strut-framed crane girder having k = 0.0001. The most uneconomical had k = 0.05 and k =∞. Eventually, the sprengel girders were found to be more profitable as compared to conventional crane girders. In the examples considered in the article, the metal savings amounted up to 14%. The presented methodology allows the calculation and designing of strut-framed crane girders with two racks to be carried out. 

  13. Wireless Smart Sensor Network System Using SmartBridge Sensor Nodes for Structural Health Monitoring of Existing Concrete Bridges

    Science.gov (United States)

    Gaviña, J. R.; Uy, F. A.; Carreon, J. D.

    2017-06-01

    There are over 8000 bridges in the Philippines today according to the Department of Public Works and Highways (DPWH). Currently, visual inspection is the most common practice in monitoring the structural integrity of bridges. However, visual inspections have proven to be insufficient in determining the actual health or condition of a bridge. Structural Health Monitoring (SHM) aims to give, in real-time, a diagnosis of the actual condition of the bridge. In this study, SmartBridge Sensor Nodes were installed on an existing concrete bridge with American Association of State Highway and Transportation Officials (AASHTO) Type IV Girders to gather vibration of the elements of the bridge. Also, standards on the effective installation of SmartBridge Sensor Nodes, such as location and orientation was determined. Acceleration readings from the sensor were then uploaded to a server, wherein they are monitored against certain thresholds, from which, the health of the bridge will be derived. Final output will be a portal or webpage wherein the information, health, and acceleration readings of the bridge will be available for viewing. With levels of access set for different types of users, the main users will have access to download data and reports. Data transmission and webpage access are available online, making the SHM system wireless.

  14. Static behaviors of long-span cable-stayed bridge; Chodai shachokyo no seiteki kyodo ni kansuru kosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Xu [Saitama Univ., Saitama (Japan). Graduate School; Yamaguchi, H.; Ito, M. [Saitama Univ., Urawa (Japan). Faculty of Engineering

    1996-04-21

    In this study, incremental equation of cable-stayed bridge is formulated by finite element method taking the geometrical nonlinear analysis into account. Then, as an example of designing a bridge with 1500m span, setting up the initial tension, analysis of in-plane behavior caused by live loads as well as analysis of the behavior against wind caused by out-of-plane wind load that are necessary for designing a bridge with 1500m span are carried out. The main results obtained through the study are as follows. As for the cable stayed bridge with 1500m center super long-span having supplementary supporting points between the side arms, the geometrical non-linearity caused by the in-plane design live loads is not remarkable. The effects of wind which acts on girders on analysis of the behaviors against wind are different depending on the aerodynamic performance of the girder and in the case of high wind speed, strong effects on the behavior against wind of the in-plane and screws generate. As the changing of tension of the cable makes influences on the force of in-plane cross section and on displacement of the girder, if the wind speed is very high, the analysis results of the behaviors against wind of in-plane and screws of the cable-stayed bridge may be different depending on in what manner the wind load on the cable to be treated. 16 refs., 16 figs., 1 tab.

  15. Increased of the capacity integral bridge with reinforced concrete beams for single span

    Science.gov (United States)

    Setiati, N. Retno

    2017-11-01

    Sinapeul Bridge that was built in 2012 in Sumedang is a bridge type using a full integral system. The prototype of integral bridge with reinforced concrete girder and single span 20 meters until this year had decreased capacity. The bridge was conducted monitoring of strain that occurs in the abutment in 2014. Monitoring results show that based on the data recorded, the maximum strain occurs at the abutment on the location of the integration of the girder of 10.59 x 10-6 tensile stress of 0.25 MPa (smaller than 150 x 10-6) with 3 MPa tensile stress as limit the occurrence of cracks in concrete. Sinapeul bridge abutment with integral system is still in the intact condition. Deflection of the bridge at the time of load test is 1.31 mm. But this time the bridge has decreased exceeded permission deflection (deflection occurred by 40 mm). Besides that, the slab also suffered destruction. One cause of the destruction of the bridge slab is the load factor. It is necessary for required effort to increase the capacity of the integral bridge with retrofitting. Retrofitting method also aims to restore the capacity of the bridge structure due to deterioration. Retrofitting can be done by shortening of the span or using Fibre Reinforced Polymer (FRC). Based on the results obtained by analysis of that method of retrofitting with Fibre Reinforced Polymer (FRC) is more simple and effective. Retrofitting with FRP can increase the capacity of the shear and bending moment becomes 41% of the existing bridge. Retrofitting with FRP method does not change the integral system on the bridge Sinapeul become conventional bridges.

  16. Implementation of a Refined Shear Rating Methodology for Prestressed Concrete Girder Bridges

    Science.gov (United States)

    2017-12-01

    Lower than desirable shear ratings at the ends of prestressed concrete beams have been the topic of ongoing research between MnDOT and the University of Minnesota. A recent study by the University of Minnesota entitled Investigation of Shear Distribu...

  17. Construction of the Usui bridge. Chodai PC shachokyo no kensetsu (Joshin'etsu jidoshado Usuikyo)

    Energy Technology Data Exchange (ETDEWEB)

    Otani, S.; Ogata, T. (Japan Highway Public Corp., Tokyo (Japan))

    1993-10-01

    The Usui Bridge is a long bridge located at the Usui mountain pass on the Joshinetsu Expressway, completed in March 1993. This paper reports from its planning to the design, construction work, and construction management. The bridge is a first two-span continuous prestressed concrete cable-stayed bridge (with a length of 222 m) with one central cable plane ever constructed as a highway bridge in Japan. Its bridge construction features are represented by the main girder consisted of three-chamber type box girder, and the main tower of reversed Y-letter concrete structure. For the fan-shaped stay cable (9-step double cable), a large capacity cable of non-grouting type fabricated at a factory (with a tensile strength of 1500 tf class) was used to simplify the installation work at the site. The one-plane structure utilizing the center belt as a stay cable fixing portion was adopted because of its economic performance superior to a two-plane structure, easiness in consolidating construction works, and assurance of more open space for car traffic. After the completion, the bridge construction has been awarded with the Tanaka Prize of Japan Society of Civil Engineers and the PC Technology Association prize. 26 figs., 4 tabs.

  18. Use and selection of bridges as day roosts by Rafinesque's Big Eared Bats.

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, Frances, M.; Loeb, Susan, C.; Bunch, Mary, S.; Bowerman, William, W.

    2008-03-01

    ABSTRACT.—Rafinesque’s big-eared bats (Corynorhinus rafinesquii) use bridges as day roosts in parts of their range, but information on bridge use across their range is lacking. From May to Aug. 2002 we surveyed 1129 bridges (12.5%) within all 46 counties of South Carolina to determine use and selection of bridges as day roosts by big-eared bats and to document their distribution across the state. During summer 2003, we visited 235 bridges in previously occupied areas of the state to evaluate short-term fidelity to bridge roosts. We found colonies and solitary big-eared bats beneath 38 bridges in 2002 and 54 bridges in 2003. Construction type and size of bridges strongly influenced use in both years; bats selected large, concrete girder bridges and avoided flat-bottomed slab bridges. The majority of occupied bridges (94.7%) were in the Upper and Lower Coastal Plains, but a few bridges (5.3%) were located in the Piedmont. Rafinesque’s big-eared bats were absent beneath bridges in the Blue Ridge Mountains. We established new records of occurrence for 10 counties. In the Coastal Plains, big-eared bats exhibited a high degree of short-term fidelity to roosts in highway bridges. For bridges that were occupied at least once, mean frequency of use was 65.9%. Probability of finding bats under a bridge ranged from 0.46 to 0.73 depending on whether the bridge was occupied in the previous year. Thus, bridges should be inspected three to five times in a given year to determine whether they are being used. Regional bridge roost surveys may be a good method for determining the distribution of C. rafinesquii, particularly in the Coastal Plains, and protection of suitable bridges may be a viable conservation strategy where natural roost sites are limited.

  19. Recessed floating pier caps for highway bridges.

    Science.gov (United States)

    1973-01-01

    Presented are alternate designs for two existing bridges in Virginia - one with steel beams and the other with prestressed concrete beams - whereby the pier caps are recessed within the depth of the longitudinal beams. The purpose of this recession i...

  20. Bridge-in-a-backpack(TM) : task 3.2: investigating soil - structure interaction - modeling and experimental results of steel arches.

    Science.gov (United States)

    2015-07-01

    This report includes fulfillment of Task 3.2 of a multi-task contract to further enhance concrete filled FRP tubes, or : the Bridge in a Backpack. Task 3 is an investigation of soil-structure interaction for the FRP tubes. Task 3.2 is the : modeling ...

  1. Disassembly of an arch bridge deformed due to landslide activity and the replacement of a new bridge in the same site. Jisuberi ni yori henkei shita arch bashi no kaitai to shinbashi no kakekae

    Energy Technology Data Exchange (ETDEWEB)

    Sano, S; Morimoto, C; Tomoda, T; Mizukawa, Y; Onushi, M; Ito, T [Kawasaki Heavy Industries, Ltd., Tokyo (Japan)

    1991-10-20

    This report describes the replacement process of an arch bridge deformed due to landslide activity, selection and contents of the disassembly method, and configuration of the new bridge and its design method. The Ryugu Bridge had been damaged by landslides over an extended period. It was a deck arch bridge having originally a span of 74 meters, but it had shortened by 424 mm due to landslide activity during 14 years since its completion. Then it was decided to be replaced by a new bridge having an adjustable structure to support the movement of its abutments. As disassembly of the deformed arch bridge could be dangerous, the best methodology was studied, and the disassembly was carried out by the cable method. The new bridge had box-girder parts in both side of the main truss, so as to be adjustable to the change of the span length, and the bridge was designed for a working life of 50 years if the bearing supports and expansion joints were reset every 10 years. Concerning the connecting parts between the box-girder and the main truss, appropriateness of the sectional configuration was verified by FEM analysis. 9 refs., 18 figs., 2 tab.

  2. Development of test method for assessing the bonding characteristics of membrane layers in wearing course laid on orthotropic steel bridge decks

    NARCIS (Netherlands)

    Liu, X.; Scarpas, A.; Li, J.; Tzimiris, G.; Hofman, R.; Voskuilen, J.

    2013-01-01

    In order to adequately characterize the adhesive bonding strength of the various membranes with surrounding materials on orthotropic steel decks and collect the necessary parameters for FE modeling, details of the Membrane Adhesion Test (MAT) are introduced. Analytical constitutive relations of the

  3. Dynamic Analysis of Cable-Stayed Bridges Affected by Accidental Failure Mechanisms under Moving Loads

    Directory of Open Access Journals (Sweden)

    Fabrizio Greco

    2013-01-01

    Full Text Available The dynamic behavior of cable-stayed bridges subjected to moving loads and affected by an accidental failure in the cable suspension system is investigated. The main aim of the paper is to quantify, numerically, the dynamic amplification factors of typical kinematic and stress design variables, by means of a parametric study developed in terms of the structural characteristics of the bridge components. The bridge formulation is developed by using a geometric nonlinear formulation, in which the effects of local vibrations of the stays and of large displacements in the girder and the pylons are taken into account. Explicit time dependent damage laws, reproducing the failure mechanism in the cable system, are considered to investigate the influence of the failure mode characteristics on the dynamic bridge behavior. The analysis focuses attention on the influence of the inertial characteristics of the moving loads, by accounting coupling effects arising from the interaction between girder and moving system. Sensitivity analyses of typical design bridge variables are proposed. In particular, the effects produced by the moving system characteristics, the tower typologies, and the failure mode characteristics involved in the cable system are investigated by means of comparisons between damaged and undamaged bridge configurations.

  4. Impact Coefficient Analysis of Long-Span Railway Cable-Stayed Bridge Based on Coupled Vehicle-Bridge Vibration

    Directory of Open Access Journals (Sweden)

    Yongle Li

    2015-01-01

    Full Text Available Compared with medium and small span bridges, very limited attention has been paid on the research of the impact coefficient of long-span railway bridges. To estimate the impact effects of long-span railway bridges subjected to moving vehicles, a real long-span railway cable-stayed bridge is regarded as the research object in this study, and a coupled model of vehicle-bridge system is established. The track irregularities are taken as the system excitation and the dynamic responses of the vehicle-bridge system are calculated. The impact effects on main girder, stayed cable, bearings, and bridge tower are discussed at various vehicle speeds. The results show that different components of the long-span railway cable-stayed bridge have different impact coefficients. Even for each part, the impact coefficient is also different at different local positions. It reveals that the impact coefficients in the actual situation may have significant differences with the related code clauses in the present design codes.

  5. Bridging Anticoagulation

    Science.gov (United States)

    ... clinical centers in the United States, Canada, and Brazil. A more detailed description of the study is ... Your Personal Message Send Message Share on Social Media Bridging Anticoagulation The BRIDGE Study Investigators Circulation. 2012; ...

  6. Impact response of RC rock-shed girder with sand cushion under falling load

    International Nuclear Information System (INIS)

    Bhatti, Abdul Qadir; Kishi, Norimitsu

    2010-01-01

    Research highlights: → An applicability of FE model of RC girders with sand cushion has been investigated. → Experimental and numerical results of Impact force, reaction force and displacement have been performed. → Cracks obtained from numerical models are in good agreement with the experimental ones. → Reaction force-displacement loops agree well between numerical and experimental results. → The configuration of the hysteretic loop at failure of RC girders can be approximated by a parallelogram. - Abstract: In order to establish a proper finite element model of prototype RC girder with sand element for impact response analysis, dynamic response analysis of RC girders with sand cushion subjected to impact force due to weight falling from the height of H = 2.5, 5, 7.5 and 10 m was performed to improve the state of the art of protective design for real scale rock-sheds by using LS-DYNA code. An applicability of proposed model was discussed comparing with experimental results (e.g. impact force, reaction force and displacement waves). From this study, dynamic characteristics of impact response can be better simulated by using the proposed model. As a result, when the sand cushion was set up, the impact force, reaction force, mid-span displacement waves, distribution of reaction force-displacement loops, and crack patterns obtained from the numerical analysis are in good agreement with those from the experimental results.

  7. Vehicle Signal Analysis Using Artificial Neural Networks for a Bridge Weigh-in-Motion System

    Directory of Open Access Journals (Sweden)

    Min-Seok Park

    2009-10-01

    Full Text Available This paper describes the procedures for development of signal analysis algorithms using artificial neural networks for Bridge Weigh-in-Motion (B-WIM systems. Through the analysis procedure, the extraction of information concerning heavy traffic vehicles such as weight, speed, and number of axles from the time domain strain data of the B-WIM system was attempted. As one of the several possible pattern recognition techniques, an Artificial Neural Network (ANN was employed since it could effectively include dynamic effects and bridge-vehicle interactions. A number of vehicle traveling experiments with sufficient load cases were executed on two different types of bridges, a simply supported pre-stressed concrete girder bridge and a cable-stayed bridge. Different types of WIM systems such as high-speed WIM or low-speed WIM were also utilized during the experiments for cross-checking and to validate the performance of the developed algorithms.

  8. Vehicle Signal Analysis Using Artificial Neural Networks for a Bridge Weigh-in-Motion System.

    Science.gov (United States)

    Kim, Sungkon; Lee, Jungwhee; Park, Min-Seok; Jo, Byung-Wan

    2009-01-01

    This paper describes the procedures for development of signal analysis algorithms using artificial neural networks for Bridge Weigh-in-Motion (B-WIM) systems. Through the analysis procedure, the extraction of information concerning heavy traffic vehicles such as weight, speed, and number of axles from the time domain strain data of the B-WIM system was attempted. As one of the several possible pattern recognition techniques, an Artificial Neural Network (ANN) was employed since it could effectively include dynamic effects and bridge-vehicle interactions. A number of vehicle traveling experiments with sufficient load cases were executed on two different types of bridges, a simply supported pre-stressed concrete girder bridge and a cable-stayed bridge. Different types of WIM systems such as high-speed WIM or low-speed WIM were also utilized during the experiments for cross-checking and to validate the performance of the developed algorithms.

  9. Exodermic bridge deck performance evaluation.

    Science.gov (United States)

    2010-07-01

    In 1998, the Wisconsin DOT completed a two"leaf bascule bridge in Green Bay with an exodermic deck system. The exodermic deck consisted of 4.5"in thick cast"in"place reinforced concrete supported by a 5.19"in tall unfilled steel grid. The concrete an...

  10. Overview of the National Timber Bridge Inspection Study

    Science.gov (United States)

    James P. Wacker; Brian K. Brashaw; Frank Jalinoos

    2013-01-01

    As many engineers begin to implement life cycle cost analyses within the preliminary bridge design phase, there is a significant need for more reliable data on the expected service life of highway bridges. Many claims are being made about the expected longevity of concrete and steel bridges, but few are based on actual performance data. Because engineers are least...

  11. Design and construction of the Daini-Chikumagawa bridge; Dai ni Chikumagawa kyoryo no sekkei to seko

    Energy Technology Data Exchange (ETDEWEB)

    Inaba, N.; Takasusuki, K.; Hirasawa, T.; Kanamori, M.

    1996-01-30

    The Daini-Chikumagawa bridge, having spans of 134m {times} 2 which is the largest in Japan as the concrete railroad, is a prestressed concrete (PC) oblique cable-stayed bridge building on the Hokuriku Shinkansen express line which is constructing towards Nagano Olympic (Feb.1998). Regarding adoption of the oblique cable-stayed bridge for the railroad bridge, there are very few examples on a global scale and in Japan besides this bridge there is only one example (Omoto bridge (Iwate pref.), span = 85m). One H type tower (H = 65m from the surface of bridge) is erected at the center of the Chikuma river and then main girders are built at the front and rear of this tower. These main girders, being separated into 5m {times} 24 blocks per one side excepting surroundings of the tower, are fabricated as a three room box type PC block (total width 12.8m; height 3.0m) each on the river beach near the spot. These blocks are jointed from the tower side by the overhanging work using the constructing vehicles and are fixed with oblique materials (cables; two face hanging system) at intervals of 10m. 4 refs., 16 figs., 5 tabs.

  12. Bridge pier foundation evaluation using cross-hole seismic tomographic imaging

    Science.gov (United States)

    Butchibabu, B.; Sandeep, N.; Sivaram, Y. V.; Jha, P. C.; Khan, P. K.

    2017-09-01

    An ambitious project connecting Jammu and Srinagar through a railway link in tectonically active and geologically complex Himalayan Mountain terrain is under progress. Under this project, the world's highest (359 m) railway arch-bridge is under construction across the River Chenab in the northern territory of India. This mega engineering structure has a two-fold ribbed arch design, comprising of steel girders. During the excavation for one of the concrete pillars on the right abutment, wide open joints and weak/shear zones were noticed. The width of these joints varies from 30 to 50 cm, trending along N170° with a dip of 65°. The foundation area of this pillar is 13 m × 24 m and on the cut slopes of the right bank of Chenab River. These exposed joints and weak zones were treated with consolidation grouting to strengthen the foundation area. To delineate the extent of these joints and weak zones below the foundation level, seismic tomography was carried out in five boreholes drilled for this purpose to cover the 300 sq-m area. The results of cross-hole seismic tomography reveals the presence of three low velocity (≤ 2600 m/s) anomalous zones below the foundation area. This also ascertained the efficacy of grouting in consolidating the joints and weak zones. Later, rock-mass quality (Q) was determined based on the relationship between the P-wave velocity and the Q-value (Barton, 2002) to infer the support system for the slope stabilization below the foundation. 3-D visualization of the seismic velocity demarcates the extent of weak or untreated zones. This methodology facilitates to update the design parameters according to Q-values during the construction stage and estimate the required level of reinforcement and support system. Similar methodology can be applicable in other areas under same site conditions.

  13. Environmental Durability of Reinforced Concrete Deck Girders Strengthened for Shear with Surface-Bonded Carbon Fiber-Reinforced Polymer

    Science.gov (United States)

    2009-05-01

    "This research investigated the durability of carbon fiber-reinforced polymer composites (CFRP) used for shear strengthening reinforced concrete deck girders. Large beams were used to avoid accounting for size effects in the data analysis. The effort...

  14. Seismic evaluation and retrofit of deteriorated concrete bridge components.

    Science.gov (United States)

    2013-06-01

    Corrosion of steel bars in reinforced concrete structures is a major durability problem for bridges constructed in the New York State : (NYS). The heavy use of deicing salt compounds this problem. Corrosion of steel bars results in loss of steel cros...

  15. Myocardial Bridging

    Directory of Open Access Journals (Sweden)

    Shi-Min Yuan

    2016-02-01

    Full Text Available Abstract Myocardial bridging is rare. Myocardial bridges are most commonly localized in the middle segment of the left anterior descending coronary artery. The anatomic features of the bridges vary significantly. Alterations of the endothelial morphology and the vasoactive agents impact on the progression of atherosclerosis of myocardial bridging. Patients may present with chest pain, myocardial infarction, arrhythmia and even sudden death. Patients who respond poorly to the medical treatment with β-blockers warrant a surgical intervention. Myotomy is a preferred surgical procedure for the symptomatic patients. Coronary stent deployment has been in limited use due to the unsatisfactory long-term results.

  16. 75 FR 62181 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

    Science.gov (United States)

    2010-10-07

    ... INFORMATION CONTACT: Ms. Ann Shemaka, Office of Bridge Technology, HIBT-30, (202) 366-1575, or Mr. Thomas Everett, Office of Bridge Technology, HIBT-30, (202) 366-4675, Federal Highway Administration, 1200 New... is categorized by the following material types, which are identified in the NBI: steel, concrete, pre...

  17. 77 FR 53251 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

    Science.gov (United States)

    2012-08-31

    ... INFORMATION CONTACT: Ms. Ann Shemaka, Office of Bridge Technology, (202) 366-1575, or via email at [email protected] or Mr. Thomas Everett, Office of Bridge Technology, (202) 366-4675, or via email at thomas... the NBI: steel, concrete, pre-stressed concrete, and other. The category ``other'' includes wood...

  18. 76 FR 55160 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

    Science.gov (United States)

    2011-09-06

    ... INFORMATION CONTACT: Ms. Ann Shemaka, Office of Bridge Technology, HIBT-30, (202) 366-1575, or Mr. Thomas Everett, Office of Bridge Technology, HIBT-30, (202) 366-4675, Federal Highway Administration, 1200 New... is categorized by the following material types, which are identified in the NBI: steel, concrete, pre...

  19. Fabrication and erection of 'Chuo ohashi bridge' for Tokyo Metropolitan Government. Tokyoto kensetsukyoku 'Chuo ohashi' no seisaku oyobi kasetsu

    Energy Technology Data Exchange (ETDEWEB)

    1994-07-01

    The present report outlines the superstructure of 'Chuo Ohashi Bridge' spanning the Sumida River, Tokyo Metropolis. Being 210.7m in length and 25.0m in breadth, that bridge is a cable-stayed bridge partially curved with a 220m radius curvature. Having a height of 76.8m, its main tower is shaped into an upside-down V with a curved top. Description of the points of which care was specially taken for the fabrication and construction in yard covers the cable anchorage of both girders and tower, assembly and welding, anti-shrinkage camber of girders, weld bevel preparation for the tower, tentative assembly, and accuracy control. Results of the wind tunnel test with a (1/50) scale model are as follows: stay cables were installed as measures against the vibration during the main tower erection. The main girders, main tower and cables were the order of superstructural erection. The cable tensioning was supervised mainly with its proper tension adjustment and subsidiarily for the configuration of bridge built. 2 refs., 10 figs., 1 tab.

  20. Low Vertical Clearance Truss Bridges : Risk Assessment and Retrofit Mitigation Study

    Science.gov (United States)

    2017-11-10

    The Washington State Department of Transportation (WSDOT) has over 60 steel truss bridges in its inventory with vertical clearances less than the minimum 16-6 required for new bridges. This study evaluates the risks of oversized vehicle impacts...

  1. Monitoring calculation of closure change of Extradosed Cable-stayed Bridge

    Science.gov (United States)

    Shi, Jing Xian; Ran, Zhi Hong

    2018-06-01

    During the construction of extradosed cable-stayed bridge in Yunnan province, China, the construction unit has made certain changes in the construction process of the closure section due to environmental restrictions: remove the hanging basket after the closure, the sling shall not be provided in closure section, the function of the sling is realized by the hanging basket on the 16th beam. In case of this change, the bridge has been constructed to section 15th. In order to ensure the smooth and orderly progress of each stage in the closure phase, this article is arranged according to the construction plan, appropriate adjustment of related procedures, checking the bridge safety at all stages of construction, the stress and force of the main girder are compared to ensure the safety of the construction after closure changes. Adjust the height of the beam of the 16th and 17th to adapt the new construction plan, and the bridge closure smoothly.

  2. APPLICATION OF ULTRA-HIGH PERFORMANCE CONCRETE TO PEDESTRIAN CABLE-STAYED BRIDGES

    Directory of Open Access Journals (Sweden)

    CHI-DONG LEE

    2013-06-01

    Full Text Available The use of ultra-high performance concrete (UHPC, which enables reducing the cross sectional dimension of the structures due to its high strength, is expected in the construction of the super-long span bridges. Unlike conventional concrete, UHPC experiences less variation of material properties such as creep and drying shrinkage and can reduce uncertainties in predicting time-dependent behavior over the long term. This study describes UHPC’s material characteristics and benefits when applied to super-long span bridges. A UHPC girder pedestrian cable-stayed bridge was designed and successfully constructed. The UHPC reduced the deflections in both the short and long term. The cost analysis demonstrates a highly competitive price for UHPC. This study indicates that UHPC has a strong potential for application in the super-long span bridges.

  3. Vibration analysis of concrete bridges during a train pass-by using various models

    International Nuclear Information System (INIS)

    Li, Qi; Wang, Ke; Cheng, Shili; Li, Wuqian; Song, Xiaodong

    2016-01-01

    The vibration of a bridge must be determined in order to predict the bridge noise during a train pass-by. It can be generally solved with different models either in the time domain or the frequency domain. The computation cost and accuracy of these models vary a lot in a wide frequency band. This study aims to compare the results obtained from various models for recommending the most suitable model in further noise prediction. First, train-track-bridge models in the time domain are developed by using the finite element method and mode superposition method. The rails are modeled by Timoshenko beam elements and the bridge is respectively modeled by shell elements and volume elements. Second, power flow models for the coupled system are established in the frequency domain. The rails are modelled by infinite Timoshenko beams and the bridge is respectively represented by three finite element models, an infinite Kirchhoff plate, and an infinite Mindlin plate model. The vibration at given locations of the bridge and the power input to the bridges through the rail fasteners are calculated using these models. The results show that the shear deformation of the bridge deck has significant influences on the bridge vibration at medium-to-high frequencies. The Mindlin plate model can be used to represent the U-shaped girder to obtain the power input to the bridge with high accuracy and efficiency. (paper)

  4. Evaluating the life cycle environmental impact of short span bridges

    DEFF Research Database (Denmark)

    Du, Guangli; Pettersson, Lars; Karoumi, Raid

    2016-01-01

    impact of the construction sector. Life cycle assessment (LCA) is a systematic method for assessing the environmental impact of products and systems, but its application in bridges is scarce. In Swede, most of the bridges are short spans and the type of concrete slab-frame bridge (CFB) accounts...... for a large share. Soil steel composite bridge (SSCB) is a functional equivalent solution for CFB. In order to mitigate the environmental burdens of short span bridges, this paper performed a comparative LCA study between these two types of bridge. The results indicate that the initial material consumption...

  5. Investigation and Control of VIVs with Multi-Lock-in Regions on Wide Flat Box Girders

    Directory of Open Access Journals (Sweden)

    Bo Wu

    2017-01-01

    Full Text Available On the preliminary designing of a wide flat box girder with the slenderness ratio 12, vertical and torsional vortex-induced vibrations (VIV are observed in wind tunnel tests. More than one lock-in region, which are defined as “multi-lock-in regions,” are recorded. Therefore, suspicions should be aroused regarding the viewpoint that wide box girders are aerodynamic friendly. As the three nascent vortexes originating at the pedestrian guardrails and inspection rails shed to near-wake through different pathways with different frequencies, the mechanisms of VIVs and multi-lock-in regions are analyzed to be determined by the inappropriate subsidiary structures. A hybrid method combining Large Eddy Simulation (LES with experimental results is introduced to study the flow-structure interactions (FSI when undergoing VIVs; the vortex mode of torsional VIV on wide flat box girders is defined as “4/2S,” which is different from any other known ones. Based on the mechanism of VIV, a new approach by increasing ventilation rate of the pedestrian guardrails is proved to be effective in suppressing vertical and torsional VIVs, and it is more feasible than other control schemes. Then, the control mechanisms are deeper investigated by analyzing the evolution of vortex mode and FSI using Hybrid-LES method.

  6. Probability Based Evaluation of Vehicular Bridge Load using Weigh-in-Motion Data

    Directory of Open Access Journals (Sweden)

    Widi Nugraha

    2016-02-01

    Full Text Available Load and Resistance Factored Design (LRFD method for designing bridge in Indonesia have been implemented for more than 25 years. LRFD method treating loads and strengths variables as random variables with specific safety factors for different loads and strengths variables type. The nominal loads, load factors, reduction factors, and other criteria for bridge design code can be determined to meet the reliability criteria. Statistical data of weigh-in-motion (WIM vehicular loads measurement in Northern Java highway, Cikampek - Pamanukan, West Java (2011, used in as statistical loads variable. A 25 m simple span bridge with reinforced concrete T-girder is used as a model for structural analysis due to WIM measured and nominal vehicular load based on RSNI T-02-2005, with applied bending moment of girder as the output. The distribution fitting result of applied bending moment due to WIM measured vehicular loads is lognormal. The maximum bending moment due to RSNI T-02-2005 nominal vehicular load is 842.45 kN-m and has probability of exceedance of 5x10-5. It can be concluded, for this study, that the bridge designed using RSNI T-02-2005 is safely designed, since it has reliability index, β of 5.02, higher than target reliability, β ranging from 3.50 or 3.72.

  7. Cable-stayed bridge No. 1 Hikihara bridge'' ( Karauko bridge'') for Kinki construction bureau, ministry of construction. Kensetsusho kinki chiho kensetsukyoku (Hikihara 1 gobashi (Karauko ohashi))no shiko

    Energy Technology Data Exchange (ETDEWEB)

    1991-11-01

    This paper summarizes the design, fabrication and erection of a back-anchor integrated single span cable suspension bridge (178 m long and 9.7 m wide) constructed over an ordinary road crossing a reservoir. This type of structure was adopted because the locational condition does not allow a bridge pier to be erected in the center of the pond, and the topography in the construction starting side has steep slopes and many places having fragile ground beds. This bridge employed precast floor plates using the Compo-Slab (manufactured by Ishikawajima Building Material Company). Main points which require attentions are listed in designing and fabricating the main towers (48 m high), main girders, and cables, as well as fabricating the precast cast floor plates (a panel has a length of 9.7 m, maximum width of 2 m, and maximum weight of 10 tons). The main towers were erected using 160-tf truck cranes, and the main girders were erected by the overhang method using 20-tf gate-type travel cranes. 3 refs., 14 figs.

  8. Exciting test of a floating type cable stayed bridge and its response observation under the typhoon; Furotiingu keishiki shachokyo (Utagenkabashi) no kishinki shiken to taifuji oto kansoku

    Energy Technology Data Exchange (ETDEWEB)

    Uno, K. [Kyushu Kyoritsu Univ., Kitakyushu (Japan). Faculty of Engineering; Aso, T. [Yamaguchi Univ., Ube (Japan). Faculty of Engineering; Kitagawa, S. [Kyushu International Univ., Kitakyushu (Japan). Faculty of Economy; Kabashima, S.

    1995-09-20

    Recently, in case of the planning and designing of bridges, of course its practicality and execution stability are considered, but consideration for landscape also is a large problem. In particular, the selection of the bridge type is very important in order to protect the beautiful natural landscape. The cable stayed bridge has become to be executed often, owing to its elegant style, however, it becomes important theme clarify the antiseismic and wind stability because of its complicated structure system and very slender girder. In this paper, the results of the dynamic characteristics of a floating type cable stayed bridge (length 292.1 m and width 14.9 m) and the observation of its dynamic behavior under the typhoon are reported. Microtremor measurement was performed to determine the dynamic characteristics of the bridge under construction. After the construction of the bridge, the excitation test was carried out in order to confirm its natural frequencies, vibration modes and damping constants. From the results of the observation of the dynamic behavior of the girder and cables under the typhoon, the wind stability of this bridge was confirmed. 10 refs., 13 figs., 9 tabs.

  9. Design of a Maglev Vibration Test Platform for the Research of Maglev Vehicle-girder Coupled Vibration Problem

    Directory of Open Access Journals (Sweden)

    Zhou Danfeng

    2017-01-01

    Full Text Available The maglev vehicle-girder coupled vibration problem has been encountered in many maglev test or commercial lines, which significantly degrade the performance of the maglev train. In previous research on the principle of the coupled vibration problem, it has been discovered that the fundamental model of the maglev girder can be simplified as a series of mass-spring resonators of different but related resonance frequencies, and that the stability of the vehicle-girder coupled system can be investigated by separately examining the stability of each mass-spring resonator – electromagnet coupled system. Based on this conclusion, a maglev test platform, which includes a single electromagnetic suspension control system, is built for experimental study of the coupled vibration problem. The guideway of the test platform is supported by a number of springs so as to change its flexibility. The mass of the guideway can also be changed by adjusting extra weights attached to it. By changing the flexibility and mass of the guideway, the rules of the maglev vehicle-girder coupled vibration problem are to be examined through experiments, and related theory on the vehicle-girder self-excited vibration proposed in previous research is also testified.

  10. A new multiconstraint method for determining the optimal cable stresses in cable-stayed bridges.

    Science.gov (United States)

    Asgari, B; Osman, S A; Adnan, A

    2014-01-01

    Cable-stayed bridges are one of the most popular types of long-span bridges. The structural behaviour of cable-stayed bridges is sensitive to the load distribution between the girder, pylons, and cables. The determination of pretensioning cable stresses is critical in the cable-stayed bridge design procedure. By finding the optimum stresses in cables, the load and moment distribution of the bridge can be improved. In recent years, different research works have studied iterative and modern methods to find optimum stresses of cables. However, most of the proposed methods have limitations in optimising the structural performance of cable-stayed bridges. This paper presents a multiconstraint optimisation method to specify the optimum cable forces in cable-stayed bridges. The proposed optimisation method produces less bending moments and stresses in the bridge members and requires shorter simulation time than other proposed methods. The results of comparative study show that the proposed method is more successful in restricting the deck and pylon displacements and providing uniform deck moment distribution than unit load method (ULM). The final design of cable-stayed bridges can be optimised considerably through proposed multiconstraint optimisation method.

  11. A New Multiconstraint Method for Determining the Optimal Cable Stresses in Cable-Stayed Bridges

    Directory of Open Access Journals (Sweden)

    B. Asgari

    2014-01-01

    Full Text Available Cable-stayed bridges are one of the most popular types of long-span bridges. The structural behaviour of cable-stayed bridges is sensitive to the load distribution between the girder, pylons, and cables. The determination of pretensioning cable stresses is critical in the cable-stayed bridge design procedure. By finding the optimum stresses in cables, the load and moment distribution of the bridge can be improved. In recent years, different research works have studied iterative and modern methods to find optimum stresses of cables. However, most of the proposed methods have limitations in optimising the structural performance of cable-stayed bridges. This paper presents a multiconstraint optimisation method to specify the optimum cable forces in cable-stayed bridges. The proposed optimisation method produces less bending moments and stresses in the bridge members and requires shorter simulation time than other proposed methods. The results of comparative study show that the proposed method is more successful in restricting the deck and pylon displacements and providing uniform deck moment distribution than unit load method (ULM. The final design of cable-stayed bridges can be optimised considerably through proposed multiconstraint optimisation method.

  12. Evaluation of continuity detail for precast prestressed girders : research project capsule.

    Science.gov (United States)

    2008-03-01

    The construction of a new bridge : crossing the Mississippi River north of : Baton Rouge is currently underway. The : project, named the John James : Audubon Bridge, is a true landmark. Its : main span will be the longest cablestayed : bridge in Nort...

  13. Proposal of self-anchored cable-supported bridge with main span length of 500m; Chuo span 500m kibo no jiteishiki tsurigatashiki kyoryo ni kansuru teian

    Energy Technology Data Exchange (ETDEWEB)

    Fukasawa, Y.; Sugiyama, T. [Yamaguchi University, Yamaguchi (Japan). Faculty of Engineering; Kaneko, S.; Mukoyama, T.; Iwaki, T. [Pacific Consultants K.K., Tokyo (Japan)

    1995-12-15

    In order to investigate the feasibility of construction of cable-supported bridge at the site where ground condition is poor and/or air route restriction shoed be considered the static and dynamic characteristics of both self-anchored cable-stayed bridge with relatively low tower and self-anchored suspension bridge have been discussed. The main span length of bridge considered here is about 500 m because of the fact that stress resultant of main girder caused by design loads is considerably lower than its design strength in the existing cable-supported bridges of this scale. The result shows that the application of both types of cable-supported bridges to the above described site may be possible as enough static safety and economy are ensured. It has been also revealed that no problem may occur from both wind and earthquake resistant viewpoints. 10 refs., 24 figs., 8 tabs.

  14. Ældre betonbroers bæreevne (Load bearing capacity of old concrete bridges)

    DEFF Research Database (Denmark)

    Nielsen, Anders

    1999-01-01

    Two old bridges have been analysed in connection with their demolition. The first one is a pedestrian bridge, the Gefion bridge, from 1894. This is the first bridge of reinforced concrete in Denmark. Here the creep in the concrete severely have changed the way in which the load on the bridge was ...... was carried. - The other is a motor way bridge from 1939, which were reinforced 1991 with external steel plates on the areas of shear on the beams. Four beams were carried to our laboratory and load tested. The steel plates have doubled the load bearing capacity of the beams....

  15. Design and Construction of Operation Bridge for Research Reactor

    International Nuclear Information System (INIS)

    Jung, Kwangsub; Choi, Jinbok; Lee, Jongmin; Oh, Jinho

    2015-01-01

    The operation bridge contains a lower working deck mounted on a saddle that travels on rails. Upright members are mounted on the saddle to support the upper structure and two hoist monorails. The saddle contains an anti-derail system that is composed of seismic lugs and guide rollers. The operation bridge travels along the rails to transport the fuel assembly, irradiated object, and reactor components in the pools by using tools. Hoists are installed at the top girder. The hoist is suspended from the monorail by means of a motor driven trolley that runs along the monorail. Movements of hoist and trolley are controlled by using the control pendant switch. Processes of design and construction of the operation bridge for the research reactor are introduced. The operation bridge is designed under consideration of functions of handling equipment in the pool and operational limits for safety. Structural analysis is carried out to evaluate the structural integrity in the seismic events. Tests and inspections are also performed during fabrication and installation to confirm the function and safety of the operation bridge

  16. National Bridge Inventory (NBI) Bridges

    Data.gov (United States)

    Department of Homeland Security — The NBI is a collection of information (database) describing the more than 600,000 of the Nation's bridges located on public roads, including Interstate Highways,...

  17. Repair systems for deteriorated bridge piles : final report.

    Science.gov (United States)

    2017-04-01

    The objective of this research project is to develop a durable repair system for deteriorated steel bridge piles that : can be implemented without the need for dewatering. A rigorous survey of the relevant practice nationwide was : conducted to infor...

  18. Synthesis of concrete bridge piles prestressed with CFRP systems.

    Science.gov (United States)

    2017-06-01

    The Texas Department of Transportation frequently constructs prestressed concrete piles for use in bridge : foundations. Such prestressed concrete piles are typically built with steel strands that are highly susceptible to : environmental degradation...

  19. Evaluation of bridge deck with shrinkage-compensating concrete.

    Science.gov (United States)

    2016-04-01

    Concrete bridge decks are susceptible to premature cracking and to corrosion of reinforcing steel. Low-permeability : concrete does not always ensure durability if the concrete has excessive cracks that facilitate the intrusion of aggressive solution...

  20. Damage Detection for Continuous Bridge Based on Static-Dynamic Condensation and Extended Kalman Filtering

    Directory of Open Access Journals (Sweden)

    Haoxiang He

    2014-01-01

    Full Text Available As an effective and classical method about physical parameter identification, extended Kalman filtering (EKF algorithm is widely used in structural damage identification, but the equations and solutions for the structure with bending deformation are not established based on EKF. The degrees of freedom about rotation can be eliminated by the static condensation method, and the dynamic condensation method considering Rayleigh damping is proposed in order to establish the equivalent and simplified modal based on complex finite element model such as continuous girder bridge. According to the requirement of bridge inspection and health monitoring, the online and convenient damage detection method based on EKF is presented. The impact excitation can be generated only on one location by one hammer actuator, and the signal in free vibration is analyzed. The deficiency that the complex excitation information is needed based on the traditional method is overcome. As a numerical example, a three-span continuous girder bridge is simulated, and the corresponding stiffness, the damage location and degree, and the damping parameter are identified accurately. It is verified that the method is suitable for the dynamic signal with high noise-signal ratio; the convergence speed is fast and this method is feasible for application.

  1. Maintained ship hull girder ultimate strength reliability considering corrosion and fatigue

    DEFF Research Database (Denmark)

    Hu, Yong; Cui, W.; Pedersen, Preben Terndrup

    2004-01-01

    The prupose of this paper is to propose a methodology to assess the time-variant ultimate strength of ship hull girder under the degradations of corrosion and fatigue. The effects of fatigue cracks on the tensile and compressive residual ultimate strength of stiffened panels and unstiffened plates......, webs and flanges, respectively. The effects of inspections and repair are taken into account. A minimum net thickness rule is used to determine repair policies. A procedure is proposed to determine the maximum allowable corrosion thickness of different parts of the hull cross section. The procedure...

  2. A Comparative Assessment of Aerodynamic Models for Buffeting and Flutter of Long-Span Bridges

    Directory of Open Access Journals (Sweden)

    Igor Kavrakov

    2017-12-01

    Full Text Available Wind-induced vibrations commonly represent the leading criterion in the design of long-span bridges. The aerodynamic forces in bridge aerodynamics are mainly based on the quasi-steady and linear unsteady theory. This paper aims to investigate different formulations of self-excited and buffeting forces in the time domain by comparing the dynamic response of a multi-span cable-stayed bridge during the critical erection condition. The bridge is selected to represent a typical reference object with a bluff concrete box girder for large river crossings. The models are viewed from a perspective of model complexity, comparing the influence of the aerodynamic properties implied in the aerodynamic models, such as aerodynamic damping and stiffness, fluid memory in the buffeting and self-excited forces, aerodynamic nonlinearity, and aerodynamic coupling on the bridge response. The selected models are studied for a wind-speed range that is typical for the construction stage for two levels of turbulence intensity. Furthermore, a simplified method for the computation of buffeting forces including the aerodynamic admittance is presented, in which rational approximation is avoided. The critical flutter velocities are also compared for the selected models under laminar flow. Keywords: Buffeting, Flutter, Long-span bridges, Bridge aerodynamics, Bridge aeroelasticity, Erection stage

  3. A numerical study on the structural integrity of self-anchored cable-stayed suspension bridges

    Directory of Open Access Journals (Sweden)

    Paolo Lonetti

    2016-10-01

    Full Text Available A generalized numerical model for predicting the structural integrity of self-anchored cable-stayed suspension bridges considering both geometric and material nonlinearities is proposed. The bridge is modeled by means of a 3D finite element approach based on a refined displacement-type finite element approximation, in which geometrical nonlinearities are assumed in all components of the structure. Moreover, nonlinearities produced by inelastic material and second order effects in the displacements are considered for girder and pylon elements, which combine gradual yielding theory with CRC tangent modulus concept. In addition, for the elements of the suspension system, i.e. stays, hangers and main cable, a finite plasticity theory is adopted to fully evaluate both geometric and material nonlinearities. In this framework, the influence of geometric and material nonlinearities on the collapse bridge behavior is investigated, by means of a comparative study, which identifies the effects produced on the ultimate bridge behavior of several sources of bridge nonlinearities involved in the bridge components. Results are developed with the purpose to evaluate numerically the influence of the material and geometric characteristics of self-anchored cable-stayed suspension bridges with respect also to conventional bridge based on cablestayed or suspension schemes

  4. Seismic Passive Control of Cable-Stayed Bridges

    Directory of Open Access Journals (Sweden)

    Hosam-Eddin M. Ali

    1995-01-01

    Full Text Available A three-dimensional modeling procedure is proposed for cable-stayed bridges with rubber, steel, and lead energy dissipation devices. The passive control technique is investigated by considering the response of bridge models with and without energy dissipation devices. The impact of various design parameters on the seismic response of current and future bridge designs is studied. Appropriate locations and properties of the passive devices can achieve better performance for cable-stayed bridges by balancing the significant reduction in earthquake-induced forces against tolerable displacements. Proper design of passive systems can help provide solutions for retro-fitting some existing bridges.

  5. Bridged graphite oxide materials

    Science.gov (United States)

    Herrera-Alonso, Margarita (Inventor); McAllister, Michael J. (Inventor); Aksay, Ilhan A. (Inventor); Prud'homme, Robert K. (Inventor)

    2010-01-01

    Bridged graphite oxide material comprising graphite sheets bridged by at least one diamine bridging group. The bridged graphite oxide material may be incorporated in polymer composites or used in adsorption media.

  6. Experimental studies of Steel Corrugated Constructions

    Directory of Open Access Journals (Sweden)

    Lazarev Yuriy

    2016-01-01

    Full Text Available The purpose of this particular article is to assess existing calculations of steel corrugated constructions. Steel Corrugated Construction is a perspective type of constructions, which is exhibiting numerous advantages in comparison with one that currently applied in automobile and railroad networks (reinforced concrete water-throughput pipes, reinforced concrete frame bridges. The evaluation of experimental data on models of constructions of this particular type has been carried out in order to improve calculations of Steel Corrugated Constructions.

  7. Teaching Steel Connections Using an Interactive Virtual Steel Sculpture

    Science.gov (United States)

    Moaveni, Saeed; Chou, Karen C.

    2015-01-01

    Steel connections play important roles in the integrity of a structure, and many structural failures are attributed to connection failures. Connections are the glue that holds a structure together. The failures of the Hartford Coliseum in 1977, the Hyatt Regency Hotel in Kansas City in 1980, and the I-35W Bridge in Minneapolis in 2007 are all…

  8. Railway bridge monitoring during construction and sliding

    Science.gov (United States)

    Inaudi, Daniele; Casanova, Nicoletta; Kronenberg, Pascal; Vurpillot, Samuel

    1997-05-01

    The Moesa railway bridge is a composite steel concrete bridge on three spans of 30 m each. The 50 cm thick concrete deck is supported on the lower flanges of two continuous, 2.7 m high I-beams. The bridge has been constructed alongside an old metallic bridge. After demolishing this one, the new bridge has been slid for 5 m by 4 hydraulic jacks and positioned on the refurbished piles of the old bridge. About 30 fiber optic, low-coherence sensors were imbedded in the concrete deck to monitor its deformations during concrete setting and shrinkage, as well as during the bridge sliding phase. In the days following concrete pour it was possible to follow its thermal expansion due to the exothermic setting reaction and the following thermal and during shrinkage. The deformations induced by the additional load produced by the successive concreting phases were also observed. During the bridge push, which extended over six hours, the embedded and surface mounted sensors allowed the monitoring of the curvature variations in the horizontal plane due to the slightly uneven progression of the jacks. Excessive curvature and the resulting cracking of concrete could be ruled out by these measurements. It was also possible to observe the bridge elongation under the heating action of the sun.

  9. Full Scale Test of a SSP 34m box girder 1. Data report

    DEFF Research Database (Denmark)

    Jensen, Find Mølholt; Branner, Kim; Nielsen, Per Hørlyk

    This report presents the setup and result of a full-scale test of a reinforced glass fibre/epoxy box girder used in 34m wind turbine blade. The tests were performed at the Blaest test facility in August 2006. The test is an important part of a research project established in cooperation between...... Risø DTU, the National Laboratory for Sustainable Energy at the Technical University of Denmark -, SSP-Technology A/S and Blaest (Blade test centre A/S) and it has been performed as a part of Find Mølholt Jensen‟s PhD study. This report contains the complete test data for the final test, in which...... the box girder was loaded until failure. A comprehensive description of the test setup is given. This report deals only with tests and results. There are no conclusions on the data in this report, but references are given to publications, where the data are used and compared with FEM etc. Various kinds...

  10. Alignment and girder position of MSE septa in the new LSS4 extraction channel of the SPS

    CERN Document Server

    Balhan, B; Rizzo, A; Weterings, W; CERN. Geneva. SPS and LHC Division

    2002-01-01

    For the extraction of the beam from the Super Proton Synchrotron (SPS) to ring 2 of the Large Hadron Collider (LHC) and the CERN Neutrino to Gran Sasso (CNGS)facility, a new fast-extraction system is being constructed in the long straight section LSS4 of the SPS. Besides extraction bumpers, enlarged aperture quadrupoles and extraction kicker magnets (MKE), six conventional DC septum magnets (MSE) are used. These magnets are mounted on a single rigid support girder, pre-aligned so as to follow the trajectory of the extracted beam and optimise the available aperture. The girder has been motorised in order to optimise the local SPS aperture during setting up, so as to avoid the risk of circulating beam impact on the septum coils. In this note, we briefly present the trajectory and apertures of the beam, we describe the calculations and methods that have been used to determine the magnet position on the girder, and finally we report on the details of the girder movement and alignment.

  11. MASH Test 3-11 on the T131RC Bridge Rail

    Science.gov (United States)

    2012-10-01

    Texas Department of Transportation (TxDOT) currently uses the TxDOT Type T101RC Bridge Rail, : a steel post and beam bridge rail anchored to the top of concrete curbs. The T101RC Bridge Rail is : 27 inches in height and can be anchored to the top of ...

  12. Building Bridges

    DEFF Research Database (Denmark)

    The report Building Bridges adresses the questions why, how and for whom academic audience research has public value, from the different points of view of the four working groups in the COST Action IS0906 Transforming Audiences, Transforming Societies – “New Media Genres, Media Literacy and Trust...... in the Media”, “Audience Interactivity and Participation”, “The Role of Media and ICT Use for Evolving Social Relationships” and “Audience Transformations and Social Integration”. Building Bridges is the result of an ongoing dialogue between the Action and non-academic stakeholders in the field of audience......, Brian O’Neill, Andra Siibak, Sascha Trültzsch-Wijnen, Nicoletta Vittadini, Igor Vobič and Frauke Zeller. Stakeholder feedback from: Michelle Arlotta (DeAgostini), Andreea M. Costache (Association of Consumers of Audiovisual Media in Catalonia/TAC), Francesco Diasio (AMARC Europe), Marius Dragomir (Open...

  13. Mathematical bridges

    CERN Document Server

    Andreescu, Titu; Tetiva, Marian

    2017-01-01

    Building bridges between classical results and contemporary nonstandard problems, Mathematical Bridges embraces important topics in analysis and algebra from a problem-solving perspective. Blending old and new techniques, tactics and strategies used in solving challenging mathematical problems, readers will discover numerous genuine mathematical gems throughout that will heighten their appreciation of the inherent beauty of mathematics. Most of the problems are original to the authors and are intertwined in a well-motivated exposition driven by representative examples. The book is structured to assist the reader in formulating and proving conjectures, as well as devising solutions to important mathematical problems by making connections between various concepts and ideas from different areas of mathematics. Instructors and educators teaching problem-solving courses or organizing mathematics clubs, as well as motivated mathematics students from high school juniors to college seniors, will find Mathematical Bri...

  14. Kawasaki Steel Giho, Vol. 27, No. 4, 1995. Special issue on steel structure

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    ;Contents (Partial): Vertical Gust Prediction of Cable-Stayed Bridges in Yawed Wind; Design and Construction of a Super Platform Structure Made of Steel; Prefabricated Steel Deck of Battledeck Floor Type for Redecking; Aesthetic Design of Structures; and Lift-up Construction Method for Multi-layer Building.

  15. Bridges Dynamic Parameters Identification Based On Experimental and Numerical Method Comparison in Regard with Traffic Seismicity

    Science.gov (United States)

    Krkošková, Katarína; Papán, Daniel; Papánová, Zuzana

    2017-10-01

    The technical seismicity negatively affects the environment, buildings and structures. Technical seismicity means seismic shakes caused by force impulse, random process and unnatural origin. The vibration influence on buildings is evaluated in the Eurocode 8 in Slovak Republic, however, the Slovak Technical Standard STN 73 0036 includes solution of the technical seismicity. This standard also classes bridges into the group of structures that are significant in light of the technical seismicity - the group “U”. Using the case studies analysis by FEM simulation and comparison is necessary because of brief norm evaluation of this issue. In this article, determinate dynamic parameters by experimental measuring and numerical method on two real bridges are compared. First bridge, (D201 - 00) is Scaffold Bridge on the road I/11 leading to the city of Čadca and is situated in the city of Žilina. It is eleven - span concrete road bridge. The railway is the obstacle, which this bridge spans. Second bridge (M5973 Brodno) is situated in the part of Žilina City on the road of I/11. It is concrete three - span road bridge built as box girder. The computing part includes 3D computational models of the bridges. First bridge (D201 - 00) was modelled in the software of IDA Nexis as the slab - wall model. The model outputs are natural frequencies and natural vibration modes. Second bridge (M5973 Brodno) was modelled in the software of VisualFEA. The technical seismicity corresponds with the force impulse, which was put into this model. The model outputs are vibration displacements, velocities and accelerations. The aim of the experiments was measuring of the vibration acceleration time record of bridges, and there was need to systematic placement of accelerometers. The vibration acceleration time record is important during the under - bridge train crossing, about the first bridge (D201 - 00) and the vibration acceleration time domain is important during deducing the force

  16. Static and Dynamic Mechanical Properties of Long-Span Cable-Stayed Bridges Using CFRP Cables

    Directory of Open Access Journals (Sweden)

    Mei Kuihua

    2017-01-01

    Full Text Available The elastic modulus and deadweight of carbon fiber-reinforced polymer (CFRP cables are different from those of steel cables. Thus, the static and dynamic behaviors of cable-stayed bridges using CFRP cables are different from those of cable-stayed bridges using steel cables. The static and dynamic performances of the two kinds of bridges with a span of 1000 m were studied using the numerical method. The effects of geometric nonlinear factors on static performance of the two kinds of cable-stayed bridges were analyzed. The live load effects and temperature effects of the two cable-stayed bridges were also analyzed. The influences of design parameters, including different structural systems, the numbers of auxiliary piers, and the space arrangement types of cable, on the dynamic performance of the cable-stayed bridge using CFRP cables were also studied. Results demonstrate that sag effect of the CFRP cable is much smaller than that of steel cable. The temperature effects of CFRP cable-stayed bridge are less than those of steel cable-stayed bridge. The vertical bending natural vibration frequency of the CFRP cable-stayed bridge is generally lower than that of steel cable-stayed bridge, whereas the torsional natural vibration frequency of the former is higher than that of the latter.

  17. Aircraft Steels

    Science.gov (United States)

    2009-02-19

    component usage. PH 13-8Mo is a precipitation-hardenable martensitic stainless steel combining excellent corrosion resistance with strength. Custom 465 is...a martensitic , age-hardenable stainless steel capable of about 1,724 MPa (250 ksi) UTS when peak-aged (H900 condition). Especially, this steel can...NOTES 14. ABSTRACT Five high strength steels (4340, 300M, AerMet 100, Ferrium S53, and Hy-Tuf) and four stainless steels (High Nitrogen, 13

  18. Modal analysis of cable-stayed UHPC bridge

    Directory of Open Access Journals (Sweden)

    Tej Petr

    2017-01-01

    Full Text Available This paper deals with the dynamic analysis of cable-stayed UHPC bridge over the Vltava river near town Melnik in Czech Republic, Europe. Bridge serves for pedestrians and cyclists. This work aims to familiarize the reader with dynamic calculations carried out and the results obtained, describing the dynamic properties of proposed bridge. The construction of bridge is designed as a cable-stayed structure with prestressed bridge deck consisting of prefabricated UHPC panels and reversed “V” shaped steel pylon with height of approximately 40 meters. The deck is anchored using 24 steel hangers in one row in a steel pylon - 17 ropes in the main span and 7 cables on the other side. Range of the main span is 99.18 meters and the secondary span is 31.9 m. Deck width is 4.5 meters with 3.0 meters passing space. The bridge is designed for the possibility of passage of vehicles weighting up to 3.5 tonnes. Deck panels are made of UHPC with reinforcement. At the edge of the bridge on the side of the shorter span the bridge deck is firmly connected with abutment and on the other deck it is stored using a pair of sliding bearings.

  19. The Assessment of the Ultimate Hull Girder Strength of RO-RO Ship after Damages

    Science.gov (United States)

    Zubair Muis Alie, Muhammad; Sitepu, Ganding; Izaak Latumahin, Samuel

    2018-03-01

    Many accidents of Ro-Ro ships happen in Indonesia such as collision and grounding. When the collision or grounding takes place on the Ro-Ro ship, the ultimate strength of hull structure after damage becomes decrease. Car and passenger decks are critical location since collision and/or grounding occur. In the present study, the assessment of the ultimate hull girder strength is conducted. The cross section of Ro-Ro ship is taken to be analyzed. The collision and grounding damages are assumed to be palced on the side and bottom area, respectively. The damages are created by removing the element from the side shell and bottom part. Finally, the result obtained is compared with one another.

  20. Analysis of post-tensioned girders structural behaviour using continuous temperature and strain monitoring

    Science.gov (United States)

    Bednarski, Ł.; Sieńko, R.; Howiacki, T.

    2017-10-01

    This article presents the possibility of using structural health monitoring system data for the analysis of structure’s operation during its life cycle. Within the specific case study it was proved, that continuous, automatic and long term monitoring of selected physical quantities such as strains and temperatures, can significantly improve the assessment of technical condition by identifying hazardous phenomena. In this work the analysis of structural behaviour of post-tensioned girders within the roofing of sport halls in Cracow, Poland, was performed based on measurement results and verified by numerical model carried out in SOFiSTiK software. Thanks to the possibility of performing calculations in real time and informing the manager of the object about abnormalities it is possible to manage the structure in effective way by, inter alia, planning the renovations or supporting decisions about snow removal.

  1. Probabilistic and sensitivity analysis of Botlek Bridge structures

    Directory of Open Access Journals (Sweden)

    Králik Juraj

    2017-01-01

    Full Text Available This paper deals with the probabilistic and sensitivity analysis of the largest movable lift bridge of the world. The bridge system consists of six reinforced concrete pylons and two steel decks 4000 tons weight each connected through ropes with counterweights. The paper focuses the probabilistic and sensitivity analysis as the base of dynamic study in design process of the bridge. The results had a high importance for practical application and design of the bridge. The model and resistance uncertainties were taken into account in LHS simulation method.

  2. Application study on the first cable-stayed bridge with CFRP cables in China

    Directory of Open Access Journals (Sweden)

    Kuihua Mei

    2015-08-01

    Full Text Available In order to push forward the development of CFRP cable-stayed bridge and accumulate experiences, the study on the application of the first cable-stayed bridge with CFRP cables in China was carried out. The design essentials of main components of the bridge were introduced and its integral performances, including static properties, dynamic properties and seismic response were analyzed using finite element method. A new bond-type anchorage was developed and the processes of fabricating and installing CFRP cables were elaborated. Based on the results of construction simulation, a tension scheme for bridge was propound. During constructing, the stresses and displacement of girder and pylon, as well as the forces and stresses of cables, were tested. The results indicate that all sections of the bridge could meet the requirements of the ultimate bearing capacity and normal service; the performance of the anchorage is good and the stresses in each cable system are similar; the tested values accord well with the calculated values. Further, creep deformation of the resin in anchorages under service load is not obvious. All these results demonstrate that the first application of CFRP cables in the cable-stayed bridge in China is successful.

  3. Design, fabrication and erection of Queen Mall Bridge; Queen mall kyo no sekkei seisaku kasetsu

    Energy Technology Data Exchange (ETDEWEB)

    Arai, M.; Ishii, A.; Shinohara, T. [Sumitomo Heavy Industries, Ltd., Tokyo (Japan)

    1997-12-20

    This paper describes design, fabrication and erection of Queen Mall Bridge, which is a new landmark in Minato-Mirai Yokohama. This bridge is two-span continuous cable stayed pedestrian bridge with a roof, and has a length 72.2 m, a width 18 m and a weight about 1,050 t. This bridge connects between the Queen`s Square and the second floor of Pacifico Yokohama. Achieving harmonious impression of the newly designed bridge in this area, glass roof was employed and all-weld method was applied to the in-site jointing of main girders and main tower in addition to the essential structural design. Since all-weld method was applied to the in-site jointing, highly accurate fabrication was considered during the in-site jointing. Due to the heavy traffic of the road below the bridge, the erection time was shortened under the severe erection conditions at night by large block method. Especially, accuracy control was considered for the whole shape management. Pre-assemble of all members was conducted just near the erection site, only 500 m away from the site, to shorten the construction time. 1 ref., 5 figs.

  4. Bridge resource program.

    Science.gov (United States)

    2013-09-01

    The mission of Rutgers Universitys Center for Advanced Infrastructure and Transportation (CAIT) Bridge Resource Program (BRP) is to provide bridge engineering support to the New Jersey Department of Transportation (NJDOT)s Bridge Engineering an...

  5. Post-buckling capacity of bi-axially loaded rectangular steel plates

    DEFF Research Database (Denmark)

    Jönsson, Jeppe; Bondum, T. H.

    2012-01-01

    slenderness and edge displacement ratio are included in the investigations presented. Capacity interaction curves are established in the bi-axial stress domain. It turns out that for certain stress ratios the imperfections dominating the ultimate capacity are not affine to the lowest classical buckling mode...... for biaxial stress. It is of great interest that short wave imperfections of a lower magnitude compared to conventionally used imperfections are seen to lower the capacity of the bi-axially loaded plates. The topic is of major concern in the flange plates of long span bridges with multi box girder...

  6. High strength reinforcing steel bars : concrete shear friction interface : final report : Part A.

    Science.gov (United States)

    2017-03-01

    High-strength steel (HSS) reinforcement, specifically ASTM A706 Grade 80 (550), is now permitted by the AASHTO LRFD Bridge Design Specifications for use in reinforced concrete bridge components in non-seismic regions. Using Grade 80 (550) steel reinf...

  7. Steel making

    CERN Document Server

    Chakrabarti, A K

    2014-01-01

    "Steel Making" is designed to give students a strong grounding in the theory and state-of-the-art practice of production of steels. This book is primarily focused to meet the needs of undergraduate metallurgical students and candidates for associate membership examinations of professional bodies (AMIIM, AMIE). Besides, for all engineering professionals working in steel plants who need to understand the basic principles of steel making, the text provides a sound introduction to the subject.Beginning with a brief introduction to the historical perspective and current status of steel making together with the reasons for obsolescence of Bessemer converter and open hearth processes, the book moves on to: elaborate the physiochemical principles involved in steel making; explain the operational principles and practices of the modern processes of primary steel making (LD converter, Q-BOP process, and electric furnace process); provide a summary of the developments in secondary refining of steels; discuss principles a...

  8. On the Effect of Hull Girder Flexibility on the Vertical Wave Bending Moment for Ultra Large Container Vessels

    DEFF Research Database (Denmark)

    Andersen, Ingrid Marie Vincent; Jensen, Jørgen Juncher

    2012-01-01

    Currently, a number of very large container ships are being built and more are on order, and some concerns have been expressed about the importance of the reduced hull girder stiffness to the wave-induced loads. The main concern is related to the fatigue life, but also a possible increase...... in the global hull girder loads as consequence of the increased hull flexibility must be considered. This is especially so as the rules of the classification societies do not explicitly account for the effect of hull flexibility on the global loads. In the present paper an analysis has been carried out...... in the waves. Slamming forces are determined by a standard momentum formulation. The hull flexibility is modelled as a nonprismatic Timoshenko beam. Generally, good agreement with experimental results and more accurate numerical predictions has previously been obtained in a number of studies. The statistical...

  9. Estimation of hull girder vertical bending moments including non-linear and flexibility effects using closed form expressions

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup; Jensen, Jørgen Juncher

    2009-01-01

    A simple but rational procedure for prediction of extreme wave-induced hull girder bending moment is presented. The procedure takes into account main ship hull characteristics such as: length, breadth, draught, block coefficient, bow flare coefficient, forward speed and hull flexibility. The wave......-linear strip theory calculations and supplemented with new closed form results for the hogging bending moment. Focus is on the extreme hull girder hogging bending moment. Due to the few input parameters this procedure can be used to estimate the wave-induced bending moments at the conceptual design phase....... Another application area is for novel single hull ship types not presently covered by the rules of the classification societies. As one application example the container ship M/S Napoli is considered....

  10. Sadhana | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Bridges are one of the most crucial facilities of transportation networks. Therefore, evaluation of the seismic vulnerability of bridge structures is perpetually regarded topic for researchers. In this study, we developed seismic fragility curves for a continuous steel box girder bridge considering the effect of differentlevels of ...

  11. Practical cable tension adjustment based upon the satisfaction concept of bridge designers; Sekkeisha no manzokudo wo koryo shita fuzzy cable choryoku choseiho

    Energy Technology Data Exchange (ETDEWEB)

    Kaneyoshi, M.; Tanaka, H. [Hitachi Zosen, Tokyo (Japan)] Furuta, H. [Kansai Univ., Osaka (Japan)

    1998-07-21

    Cable tension adjustment of bridge beam of cable stayed bridge and so forth that uses cable as a structural element is classified into (1) pre-stress adjustment of cable at design level, (2) slim adjustment required at erection level. The former deals with the structurally high dimensional statically indeterminate structures like cable-stayed bridges and is a process for carrying out economical design by making the stress resultant of main girder small due to the introduction of appropriate pre-stress stress on this cable. The later is the process of getting rid off the errors caused in cable tension and camber of girder and tower regarding various errors such as design, fabrication and erection errors. The authors developed analysis method using fuzzy regression analysis and this has been applied in number of practical bridges. In this research, much more practical method is developed where the aspire of designer can be introduced easily by applying the satisfaction concept. By using this, pre-stress adjustment and shim adjustment of cable can be possible in a practical way. 9 refs., 7 figs., 8 tabs.

  12. Full scale test of a SSP 34m box girder 1. Data report; Reinforced glass fiber/expoxy used in wind turbine blades

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Find M.; Branner, K.; Nielsen, Per H. (and others)

    2008-03-15

    This report presents the setup and result of a full-scale test of a reinforced glass fibre/epoxy box girder used in 34m wind turbine blade. The tests were performed at the Blaest test facility in August 2006. The test is an important part of a research project established in cooperation between Risoe DTU, the National Laboratory for Sustainable Energy at the Technical University of Denmark -, SSP-Technology A/S and Blaest (Blade test centre A/S) and it has been performed as a part of Find Moelholt Jensen's PhD study. This report contains the complete test data for the final test, in which the box girder was loaded until failure. A comprehensive description of the test setup is given. This report deals only with tests and results. There are no conclusions on the data in this report, but references are given to publications, where the data are used and compared with FEM etc. Various kinds of measuring equipment have been used during these tests: acoustic emission, 330 strain gauges, 24 mechanical displacement devices and two optical deformation measuring systems. The mechanical displacement devices measured both global (absolute) and local (relative) deflection and the optical systems measured surface deformation. A prediction was made on the location of the failure of the girder. At this location the majority of the measuring equipment was concentrated. The prediction was proved to be correct and valuable information of the behaviour of the box girder prior to failure was obtained. The experimental investigation consisted of the following load configurations: -Flapwise bending -Torsion Ultrasonic scanning of the box girder was performed before, during and after the test the box girder. This was done to investigate whether the girder was damaged by the load or imperfection (productions defects) growth. (au)

  13. Energy-based damping evaluation of cable-stayed bridges and its application to Tsurumi Tsubasa bridge; Shachokyo shindo gensui no energy teki hyokaho to Tsurumi Tsubasakyo eno tekiyo

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, H. [Saitama University, Saitama (Japan). Faculty of Engineering; Takano, H.; Ogasawara, M.; Shimosato, T. [Metropolitan Expressway Public Corp., Tokyo (Japan); Kato, M.; Kato, H. [NKK Corp., Tokyo (Japan)

    1996-07-21

    This paper provides and discusses a more common energy-based evaluation method of vibration damping in cable-stayed bridges. This method was applied to data obtained from the field vibration test of the Tsurumi Tsubasa Bridge. The damping was defined as dissipation energy in one cycle against the total potential energy. The dissipation energy from shoe friction, aerodynamic damping, and dampers for cables was added to the method proposed by Yamaguchi, et. al., in which the energy of girders, towers, and cables were quantitated, and the dissipation energy was determined from the loss factor of each constituent, to evaluate the damping of whole bridge. Thus, a more common energy-based evaluation method was provided. This method was applied to the damping obtained from the field vibration test of Tsurumi Tsubasa Bridge. Consequently, it was found that the damping of whole bridge was significantly affected by the shoe friction, aerodynamic damping, and dampers for cables. Distinguished damping characteristics of the Tsurumi Tsubasa Bridge could be explained by the energy-based evaluation. Validity of the energy-based evaluation method for damping of cable-stayed bridges was demonstrated. 15 refs., 9 figs., 6 tabs.

  14. Dynamic response of the train-track-bridge system subjected to derailment impacts

    Science.gov (United States)

    Ling, Liang; Dhanasekar, Manicka; Thambiratnam, David P.

    2018-04-01

    Derailments on bridges, although not frequent, when occurs due to a complex dynamic interaction of the train-track-bridge structural system, are very severe. Furthermore, the forced vibration induced by the post-derailment impacts can toss out the derailed wagons from the bridge deck with severe consequences to the traffic underneath and the safety of the occupants of the wagons. This paper presents a study of the train-track-bridge interaction during a heavy freight train crossing a concrete box girder bridge from a normal operation to a derailed state. A numerical model that considers the bridge vibration, train-track interaction and the train post-derailment behaviour is formulated based on a coupled finite-element - multi-body dynamics (FE-MBD) theory. The model is applied to predict the post-derailment behaviour of a freight train composed of one locomotive and several wagons, as well as the dynamic response of a straight single-span simply supported bridge containing ballast track subjected to derailment impacts. For this purpose, a typical derailment scenario of a heavy freight train passing over a severe track geometry defect is introduced. The dynamic derailment behaviour of the heavy freight train and the dynamic responses of the rail bridge are illustrated through numerical examples. The results exhibit the potential for tossing out of the derailed trains from the unstable increase in the yaw angle signature and a lower rate of increase of the bridge deck bending moment compared to the increase in the static axle load of the derailed wheelset.

  15. Construction of cable-stayed prestressed concrete bridge, having Japan`s first independent single slanted tower; Nippon hatsu no keisha shuto wo motsu PC shachokyo no seko

    Energy Technology Data Exchange (ETDEWEB)

    Sanada, Y.; Naito, H. [Penta-Ocean Construction Co. Ltd., Tokyo (Japan); Takeuchi, H.; Mikami, T.

    1994-08-01

    In the Hachinoe Harbor, Aomori prefecture, a man-made island (Hachinoe Port Island) is being constructed by reclamation. When proceeding this undertaking plan, a construction of the Hachinoe Harbor Port Island connection bridge, which connects the man-made island with the existing harbor district, was made an urgent necessity. This connecting bridge is a bridge with a total length of 256.56m, and is constituted of two span continuous PC slanted bridge and three span continuous PC box girder bridge. This slanted bridge has become an asymmetrical structure due to several conditions coming from a plan, and moreover it has the first structural shape as a road bridge in Japan, of which main tower is 15{degree} slanted independent single tower type, there are more problems for the work execution compared with other normal slanted bridges. In addition, because it is situated in an extremely cruel environment like in the cold region and in the marine environment, a sufficient consideration is required for its design and work execution in order to insure a durability. In this report, an outline of work execution content about PC slanted bridge part currently under a construction zealously aiming at a completion in the end of the fiscal year 1994 is introduced. 2 refs., 14 figs., 4 tabs.

  16. RECONSTRUCTION AND REINFORCEMENT OF BRIDGE ACROSS THE RIVER. SYLVA IN KUNGUR, RUSSIA

    Directory of Open Access Journals (Sweden)

    R. Ye. Heizn

    2010-04-01

    Full Text Available Sylva Bridge at Kungur city is one of the oldest road bridges in Perm region, the West Urals, Russia. Its erection was begun in 1912 and was interrupted with the First World War and the further events in Russia. The bridge was opened only in 1931. For 75 years of bridge operation the most part of bridge constructions has been acquired plural damages, both mechanical and corrosion. After the bridge inspection in 2003 and according to the calculations of its capacity, the decision on reconstruction of the bridge was accepted. The purpose of rehabilitation was to replace the timber deck by steel orthotropic deck with asphalt pavement. A new deck was to be engaged in combined action with the existing metal structures with the help of socles with high-strength bolts. Due to this, the bridge carrying capacity was increased as required by the present standards. In 2006, after tests, the bridge was opened for traffic.

  17. Aeroelastic Response from Indicial Functions with a Finite Element Model of a Suspension Bridge

    Science.gov (United States)

    Mikkelsen, O.; Jakobsen, J. B.

    2017-12-01

    The present paper describes a comprehensive analysis of the aeroelastic bridge response in time-domain, with a finite element model of the structure. The main focus is on the analysis of flutter instability, accounting for the wind forces generated by the bridge motion, including twisting as well as vertical and horizontal translation, i.e. all three global degrees of freedom. The solution is obtained by direct integration of the equations of motion for the bridge-wind system, with motion-dependent forces approximated from flutter derivatives in terms of rational functions. For the streamlined bridge box-girder investigated, the motion dependent wind forces related to the along-wind response are found to have a limited influence on the flutter velocity. The flutter mode shapes in the time-domain and the frequency domain are consistent, and composed of the three lowest symmetrical vertical modes coupled with the first torsional symmetric mode. The method applied in this study provides detailed response estimates and contributes to an increased understanding of the complex aeroelastic behaviour of long-span bridges.

  18. Increasing the Capacity of Existing Bridges by Using Unbonded Prestressing Technology: A Case Study

    Directory of Open Access Journals (Sweden)

    Antonino Recupero

    2014-01-01

    Full Text Available External posttensioning or unbonded prestressing was found to be a powerful tool for retrofitting and for increasing the life extension of existing structures. Since the 1950s, this technique of reinforcement was applied with success to bridge structures in many countries, and was found to provide an efficient and economic solution for a wide range of bridge types and conditions. Unbonded prestressing is defined as a system in which the post-tensioning tendons or bars are located outside the concrete cross-section and the prestressing forces are transmitted to the girder through the end anchorages, deviators, or saddles. In response to the demand for a faster and more efficient transportation system, there was a steady increase in the weight and volume of traffic throughout the world. Besides increases in legal vehicle loads, the overloading of vehicles is a common problem and it must also be considered when designing or assessing bridges. As a result, many bridges are now required to carry loads significantly greater than their original design loads; and their deck results still deteriorated by cracking of concrete, corrosion of rebars, snapping of tendons, and so forth. In the following, a case study about a railway bridge retrofitted by external posttensioning technique will be illustrated.

  19. A FULL-SCALE MEASUREMENT OF WIND ACTIONS AND EFFECTS ON A SEA-CROSSING BRIDGE

    Directory of Open Access Journals (Sweden)

    Yi Zhou

    2017-10-01

    Full Text Available Wind loading is critical for the large-span and light-weight structures, and field measurement is the most effective way to evaluate the wind resistance performance of a specific structure. This study investigates the wind characteristics and wind-induced vibration on a sea-crossing bridge in China, namely Donghai Bridge, based on up to six years of monitoring data. It is found that: (1 there exists obvious discrepancy between the measured wind field parameters and the values suggested by the design code; and the wind records at the bridge site is easily interfered by the bridge structure itself, which should be considered in interpreting the measurements and designing structural health monitoring systems (SHMS; (2 for strong winds with high non-stationarity, a shorter averaging time than 10-min is preferable to obtain more stable turbulent wind characteristics; (3 the root mean square (RMS of the wind-induced acceleration of the girder may increase in an approximately quadratic curve relationship with the mean wind speed; and (4 compared to traffic load, the wind dominates the girder’s lateral vibration amplitude, while the heavy-load traffic might exert more influence on the girder’s vertical and torsional vibrations than the high winds. This study provides field evidence for the wind-resistant design and evaluation of bridges in similar operational conditions.

  20. Effect of Piers Shape on the Dynamic Structural Responses of Prestressed Concrete Bridge: Part II

    Directory of Open Access Journals (Sweden)

    Ali Fadhil Naser

    2016-03-01

    Full Text Available Pier of bridge is usually used as a general term for any type of substructure located between horizontal spans and foundations. Piers give vertical supports for spans at intermediate points and perform two main functions. The objective of this study is to inspect the effect of piers shape on the dynamic structural performance by adopting theoretical dynamic analysis. The results of dynamic analysis of 25 bridges models show that the maximum value of natural frequency is equal to 5.64Hz in two circles piers bridge model. Therefore, this type of model has good stiffness and bearing capacity. The two square piers model, the one circle pier model, and the two circles piers model appear good stiffness because of the natural frequencies (5.30Hz, 5.52Hz, and 5.64Hz are more than the maximum forced frequencies (4.52Hz, 5.45Hz, and 4.52Hz respectively. According to the comparison between all models results, the two circles piers model has the higher stiffness because of this model has the maximum value of natural frequency (5.64Hz and it is more than all forced vibration frequencies of all others models. Therefore, this study recommends that using the bridge model of two circles piers in the bridges construction that consists of three spans (30m+40m+30m with section of box girder.

  1. Effect of Piers Shape on the Dynamic Structural Responses of Prestressed Concrete Bridge: Part II

    Directory of Open Access Journals (Sweden)

    Ali Fadhil Naser

    2016-12-01

    Full Text Available Pier of bridge is usually used as a general term for any type of substructure located between horizontal spans and foundations. Piers give vertical supports for spans at intermediate points and perform two main functions. The objective of this study is to inspect the effect of piers shape on the dynamic structural performance by adopting theoretical dynamic analysis. The results of dynamic analysis of 25 bridges models show that the maximum value of natural frequency is equal to 5.64Hz in two circles piers bridge model. Therefore, this type of model has good stiffness and bearing capacity. The two square piers model, the one circle pier model, and the two circles piers model appear good stiffness because of the natural frequencies (5.30Hz, 5.52Hz, and 5.64Hz are more than the maximum forced frequencies (4.52Hz, 5.45Hz, and 4.52Hz respectively. According to the comparison between all models results, the two circles piers model has the higher stiffness because of this model has the maximum value of natural frequency (5.64Hz and it is more than all forced vibration frequencies of all others models. Therefore, this study recommends that using the bridge model of two circles piers in the bridges construction that consists of three spans (30m+40m+30m with section of box girder.

  2. Wind tunnel test of musi VI bridge

    Science.gov (United States)

    Permata, Robby; Andika, Matza Gusto; Syariefatunnisa, Risdhiawan, Eri; Hermawan, Budi; Noordiana, Indra

    2017-11-01

    Musi VI Bridge is planned to cross the Musi River in Palembang City, South Sumatera Province, Indonesia. The main span is a steel arch type with 200 m length and side span length is 75 m. Finite element analysis results showed that the bridge has frequency ratio for torsional and heaving mode (torsional frequency/heaving frequency)=1.14. This close to unity value rises concern about aerodynamic behaviour and stability of the bridge deck under wind loading. Sectional static and free vibration wind tunnel test were performed to clarify this phenomena in B2TA3 facility in Serpong, Indonesia. The test followed the draft of Guide of Wind Tunnel Test for Bridges developed by Indonesian Ministry of Public Works. Results from wind tunnel testing show that the bridge is safe from flutter instability and no coupled motion vibration observed. Therefore, low value of frequency ratio has no effect to aerodynamic behaviour of the bridge deck. Vortex-induced vibration in heaving mode occurred in relatively low wind velocity with permissible maximum amplitude value.

  3. Probabilistic Model for Fatigue Crack Growth in Welded Bridge Details

    DEFF Research Database (Denmark)

    Toft, Henrik Stensgaard; Sørensen, John Dalsgaard; Yalamas, Thierry

    2013-01-01

    In the present paper a probabilistic model for fatigue crack growth in welded steel details in road bridges is presented. The probabilistic model takes the influence of bending stresses in the joints into account. The bending stresses can either be introduced by e.g. misalignment or redistribution...... of stresses in the structure. The fatigue stress ranges are estimated from traffic measurements and a generic bridge model. Based on the probabilistic models for the resistance and load the reliability is estimated for a typical welded steel detail. The results show that large misalignments in the joints can...

  4. Reducing Local Scouring at Bridge Piles Using Collars and Geobags

    Directory of Open Access Journals (Sweden)

    Shatirah Akib

    2014-01-01

    Full Text Available The present study examines the use of collars and geobags for reducing local scour around bridge piles. The efficiency of collars and geobags was studied experimentally. The data from the experiments were compared with data from earlier studies on the use of single piles with a collar and with a geobag. The results showed that using a combination of a steel collar and a geobag yields the most significant scour reduction for the front and rear piles, respectively. Moreover, the independent steel collar showed better efficiency than the independent geobag below the sediment level around the bridge piles.

  5. Carbon Fiber Reinforced Polymer Grids for Shear and End Zone Reinforcement in Bridge Beams

    Science.gov (United States)

    2018-01-01

    Corrosion of reinforcing steel reduces life spans of bridges throughout the United States; therefore, using non-corroding carbon fiber reinforced polymer (CFRP) reinforcement is seen as a way to increase service life. The use of CFRP as the flexural ...

  6. Vulnerabilidad sísmica y capacidad de carga de un puente en acero basado en confiabilidad estructural Seismic vulnerability and load carrying capacity studies of a steel bridge based on structural relia

    Directory of Open Access Journals (Sweden)

    Edgar Muñoz

    2008-01-01

    Full Text Available Por medio de la confiabilidad estructural, para un Puente en Colombia después de su monitoreo. Los resultados de este trabajo son parte de una nueva metodología para evaluar puentes existentes mediante una colaboración entre Universidad-Empresas-Gobierno Nacional. Este estudio ayuda en la toma de decisiones y en la priorización de tareas de rehabilitación. Este estudio incluyó: caracterización dinámica de las vibraciones naturales del puente; adquisición de datos de fuerzas internas debidas al tráfico por medio de tecnología de LVDT's y Strain Gages; evaluación de las fuerzas actuales comparadas contra los esfuerzos máximos permitidos; modelación estática, dinámica y estructural. Adicionalmente se hizo un estudio de amenaza sísmica y respuesta dinámica del área del puente y nueve (9 diferentes espectros de respuesta fueron obtenidos, cada uno con un periodo de retorno diferente. Se encontró que las torres del puente tienen una probabilidad de falla mayor que la permitida por los códigos. Lo anterior condujo a un reforzamiento inmediato del puente.In this document, seismic vulnerability and load carrying capacity analyses are presented for a bridge in Colombia after monitoring by means of reliability of structures. Results of this work are part of a new methodology to evaluate existing bridges carried out though a partnership among University - Private Companies - and Goverment. This study helps in decision making on the priority of rehabilitation tasks. This study included: dynamic characterization of natural vibrations of the bridge; data logging of inner forces due to traffic by using LVDT's and strain gages technology; evaluation of actual forces to be compared to allowed stresses, dynamic and static structural modelling. Also, a seismic hazard and dynamic response of the local area of the bridge was developed and nine (9 different response spectra were obtained, each one varying its return period. It was found that the

  7. Safety Analysis of the Patch Load Resistance of Plate Girders: Influence of Model Error and Variability

    Directory of Open Access Journals (Sweden)

    Farzad Shahabian

    2013-12-01

    Full Text Available This study aims to undertake a statistical study to evaluate the accuracy of nine models that have been previously proposed for estimating the ultimate resistance of plate girders subjected to patch loading. For each model, mean errors and standard errors, as well as the probability of underestimating or overestimating patch load resistance, are estimated and the resultant values are compared one to another. Prior to that, the models are initially calibrated in order to improve interaction formulae using an experimental data set collected from the literature. The models are then analyzed by computing design factors associated with a target risk level (probability of exceedance. These models are compared one to another considering uncertainties existed in material and geometrical properties. The Monte Carlo simulation method is used to generate random variables. The statistical parameters of the calibrated models are calculated for various coefficients of variations regardless of their correlation with the random resistance variables. These probabilistic results are very useful for evaluating the stochastic sensitivity of the calibrated models.

  8. Wire position system to consistently measure and record the location change of girders following ground changes

    Science.gov (United States)

    Choi, H. J.; Lee, S. B.; Lee, H. G.; Y Back, S.; Kim, S. H.; Kang, H. S.

    2017-07-01

    Several parts that comprise the large scientific device should be installed and operated at the accurate three-dimensional location coordinates (X, Y, and Z) where they should be subjected to survey and alignment. The location of the aligned parts should not be changed in order to ensure that the electron beam parameters (Energy 10 GeV, Charge 200 pC, and Bunch Length 60 fs, Emittance X/Y 0.481 μm/0.256 μm) of PAL-XFEL (X-ray Free Electron Laser of the Pohang Accelerator Laboratory) remain stable and can be operated without any problems. As time goes by, however, the ground goes through uplift and subsidence, which consequently deforms building floors. The deformation of the ground and buildings changes the location of several devices including magnets and RF accelerator tubes, which eventually leads to alignment errors (∆X, ∆Y, and ∆Z). Once alignment errors occur with regard to these parts, the electron beam deviates from its course and beam parameters change accordingly. PAL-XFEL has installed the Hydrostatic Leveling System (HLS) to measure and record the vertical change of buildings and ground consistently and systematically and the Wire Position System (WPS) to measure the two dimensional changes of girders. This paper is designed to introduce the operating principle and design concept of WPS and discuss the current situation regarding installation and operation.

  9. Effects of Common Structural Rules on hull-girder reliability of an Aframax oil tanker

    International Nuclear Information System (INIS)

    Parunov, Josko; Guedes Soares, C.

    2008-01-01

    This paper aims at quantifying the changes in notional reliability levels that result from redesigning an existing Aframax tanker to comply with the Common Structural Rules (CSR) for double-hull oil tankers. The probability of structural failure is calculated using the first-order reliability method. The evaluation of the wave-induced load effects that occur during long-term operation of the ship in the seaway is carried out in accordance with the International Association of Classification Societies (IACS)-recommended procedure, while transfer functions are calculated using the sink-source 3D linear method. The still-water loads are defined on the basis of a statistical analysis of loading conditions from the loading manual. The ultimate collapse bending moment of the midship cross section, which is used as the basis for the reliability formulation, is evaluated by progressive collapse analysis and by a single-step procedure according to CSR. The reliability assessment is performed for 'as-built' and 'corroded' states of the existing ship and a reinforced ship complying with CSR. It is shown that the hull-girder failure probability of an Aframax tanker is reduced several times due to the reinforcements according to CSR. Sensitivity analysis and a parametric study are performed to investigate the variability of results with the change of parameters of pertinent random variables within their plausible ranges. Finally, differences between load combination approaches by Ferry-Borges and Castanheta method and Turkstra's rule are investigated

  10. Economical bridge solutions based on innovative composite dowels and integrated abutments ecobridge

    CERN Document Server

    Băncilă, Radu

    2015-01-01

    This book is an outcome of the research project “ECOBRIDGE – Demonstration of ECOnomical BRIDGE solutions based on innovative composite dowels and integrated abutments – RFCS – CT 2010-00024”, which has been co-funded by the Research Fund for Coal and Steel (R.F.C.S.) of the European Community. The main topics of the book are the following: design of integral bridges, innovative composite dowels for the shear transmission, construction of bridges, structural analysis of bridges and monitoring. The book joins the technical experience and the contributions of the involved research partners. The technical content of all the papers is present-day in the field of the design, construction and monitoring of innovative composite bridges. The efficient design and construction improve and consolidate the market position of steel construction and steel producing industry. In addition, the advanced forms of construction are contributing to savings in material and energy consumption for the structure during prod...

  11. Assessment of the transportation route of oversize and excessive loads in relation to the load-bearing capacity of existing bridges

    Science.gov (United States)

    Doležel, Jiří; Novák, Drahomír; Petrů, Jan

    2017-09-01

    Transportation routes of oversize and excessive loads are currently planned in relation to ensure the transit of a vehicle through critical points on the road. Critical points are level-intersection of roads, bridges etc. This article presents a comprehensive procedure to determine a reliability and a load-bearing capacity level of the existing bridges on highways and roads using the advanced methods of reliability analysis based on simulation techniques of Monte Carlo type in combination with nonlinear finite element method analysis. The safety index is considered as a main criterion of the reliability level of the existing construction structures and the index is described in current structural design standards, e.g. ISO and Eurocode. An example of a single-span slab bridge made of precast prestressed concrete girders of the 60 year current time and its load bearing capacity is set for the ultimate limit state and serviceability limit state. The structure’s design load capacity was estimated by the full probability nonlinear MKP analysis using a simulation technique Latin Hypercube Sampling (LHS). Load-bearing capacity values based on a fully probabilistic analysis are compared with the load-bearing capacity levels which were estimated by deterministic methods of a critical section of the most loaded girders.

  12. Structural Behavior of a Long-Span Partially Earth-Anchored Cable-Stayed Bridge during Installation of a Key Segment by Thermal Prestressing

    Directory of Open Access Journals (Sweden)

    Sang-Hyo Kim

    2016-08-01

    Full Text Available This study investigated structural behavior of long-span partially earth-anchored cable-stayed bridges with a main span length of 810 m that use a new key segment closing method based on a thermal prestressing technique. A detailed construction sequence analysis matched with the free cantilever method (FCM was performed using a three-dimensional finite element (FE model of a partially earth-anchored cable-stayed bridge. The new method offers an effective way of connecting key segments by avoiding large movements resulting from the removal of the longitudinal restraint owing to the asymmetry of axial forces in the girders near the pylons. The new method develops new member forces through the process of heating the cantilever system before installing the key segment and cooling the system continuously after installing key segments. The resulting forces developed by the thermal process enhance the structural behavior of partially earth-anchored cable-stayed bridges owing to decreased axial forces in the girders.

  13. Investigation of long-term prestress losses in pretensioned high performance concrete girders.

    Science.gov (United States)

    2005-01-01

    Effective determination of long-term prestress losses is important in the design of prestressed concrete bridges. Over-predicting prestress losses results in an overly conservative design for service load stresses, and under-predicting prestress loss...

  14. Stålplader gav dobbelt bæreevne (Steel plates doubled the load bearing capacity)

    DEFF Research Database (Denmark)

    Nielsen, Jan Broch

    1999-01-01

    Abstract from an examination of motor road bridge beams reinforced with steel plates on the sides and bottom. The plates doubled the load bearing capacity of the beams.......Abstract from an examination of motor road bridge beams reinforced with steel plates on the sides and bottom. The plates doubled the load bearing capacity of the beams....

  15. Instrumentation of the US grant bridge for monitoring of fabrication, erection, in-service behavior, and to support management, maintenance, and inspection.

    Science.gov (United States)

    2013-12-01

    The replacement of the US Grant Bridge over the Ohio River in Portsmouth, OH, was initiated in : 2001 when the original bridge was closed and demolished, and its substitute opened in 2006. The : new design is a steel cable stay design with steel gird...

  16. Simplified Analytical Method for Optimized Initial Shape Analysis of Self-Anchored Suspension Bridges and Its Verification

    Directory of Open Access Journals (Sweden)

    Myung-Rag Jung

    2015-01-01

    Full Text Available A simplified analytical method providing accurate unstrained lengths of all structural elements is proposed to find the optimized initial state of self-anchored suspension bridges under dead loads. For this, equilibrium equations of the main girder and the main cable system are derived and solved by evaluating the self-weights of cable members using unstrained cable lengths and iteratively updating both the horizontal tension component and the vertical profile of the main cable. Furthermore, to demonstrate the validity of the simplified analytical method, the unstrained element length method (ULM is applied to suspension bridge models based on the unstressed lengths of both cable and frame members calculated from the analytical method. Through numerical examples, it is demonstrated that the proposed analytical method can indeed provide an optimized initial solution by showing that both the simplified method and the nonlinear FE procedure lead to practically identical initial configurations with only localized small bending moment distributions.

  17. Bridge element deterioration rates.

    Science.gov (United States)

    2008-10-01

    This report describes the development of bridge element deterioration rates using the NYSDOT : bridge inspection database using Markov chains and Weibull-based approaches. It is observed : that Weibull-based approach is more reliable for developing b...

  18. Bridge vehicle impact assessment.

    Science.gov (United States)

    2011-12-01

    Bridges in New York State have been experiencing close to 200 bridge hits a year. These : accidents are attributed to numerous factors including: improperly stored equipment on trucks; : violation of vehicle posting signs; illegal commercial vehicles...

  19. Bridge Scour Technology Transfer

    Science.gov (United States)

    2018-01-24

    Scour and flooding are the leading causes of bridge failures in the United States and therefore should be monitored. New applications of tools and technologies are being developed, tested, and implemented to reduce bridge scour risk. The National Coo...

  20. LTBP bridge performance primer.

    Science.gov (United States)

    2013-12-01

    "The performance of bridges is critical to the overall performance of the highway transportation system in the United States. However, many critical aspects of bridge performance are not well understood. The reasons for this include the extreme diver...

  1. Environmental life cycle assessment of railway bridge materials using UHPFRC

    Directory of Open Access Journals (Sweden)

    Bizjak Karmen Fifer

    2016-10-01

    Full Text Available The railway infrastructure is a very important component of the world’s total transportation network. Investment in its construction and maintenance is significant on a global scale. Previously published life cycle assessment (LCA studies performed on road and rail systems very seldom included infrastructures in detail, mainly choosing to focus on vehicle manufacturing and fuel consumption. This article presents results from an environmental study for railway steel bridge materials for the demonstration case of the Buna Bridge in Croatia. The goal of these analyses was to compare two different types of remediation works for railway bridges with different materials and construction types. In the first part, the environmental impact of the classical concrete bridge construction was calculated, whereas in the second one, an alternative new solution, namely, the strengthening of the old steel bridge with ultra-high-performance fibre-reinforced concrete (UHPFRC deck, was studied. The results of the LCA show that the new solution with UHPFRC deck gives much better environmental performance. Up to now, results of LCA of railway open lines, railway bridges and tunnels have been published, but detailed analyses of the new solution with UHPFRC deck above the old bridge have not previously been performed.

  2. Environmental life cycle assessment of railway bridge materials using UHPFRC

    Science.gov (United States)

    Bizjak, Karmen Fifer; Šajna, Aljoša; Slanc, Katja; Knez, Friderik

    2016-10-01

    The railway infrastructure is a very important component of the world's total transportation network. Investment in its construction and maintenance is significant on a global scale. Previously published life cycle assessment (LCA) studies performed on road and rail systems very seldom included infrastructures in detail, mainly choosing to focus on vehicle manufacturing and fuel consumption. This article presents results from an environmental study for railway steel bridge materials for the demonstration case of the Buna Bridge in Croatia. The goal of these analyses was to compare two different types of remediation works for railway bridges with different materials and construction types. In the first part, the environmental impact of the classical concrete bridge construction was calculated, whereas in the second one, an alternative new solution, namely, the strengthening of the old steel bridge with ultra-high-performance fibre-reinforced concrete (UHPFRC) deck, was studied. The results of the LCA show that the new solution with UHPFRC deck gives much better environmental performance. Up to now, results of LCA of railway open lines, railway bridges and tunnels have been published, but detailed analyses of the new solution with UHPFRC deck above the old bridge have not previously been performed.

  3. Cable Supported Bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    Cable supported bridges in the form of suspension bridges and cable-stayed bridges are distinguished by their ability to overcome large spans.The book concentrates on the synthesis of cable supported bridges, covering both design and construction aspects. The analytical part covers simple methods...... to quantify the different structural configurations and allows a preliminary optimization of the main structure.Included are the most recent advances in structural design, corrosion protection of cables, aerodynamic safety, and erection procedures....

  4. Sensing and Rating of Vehicle–Railroad Bridge Collision

    DEFF Research Database (Denmark)

    Vemuganti, Shreya; Ozdagli, Ali I.; Liu, Bideng

    2017-01-01

    Overhead collisions of trucks with low-clearance railway bridges cause more than half of the railway traffic interruptions over bridges in the United States. Railroad owners are required to characterize the damage caused by such events and assess the safety of subsequent train crossings. However...... and remotely quantify damage. This research proposes an impact rating strategy based on the information that best describes the consequences of vehicle-railway bridge collisions. A series of representative impacts were simulated using numerical finite element models of a steel railway bridge. Railway owners...... provided information about the bridge and impact characterization based on railway industry experience. The resulting nonlinear dynamic responses were evaluated with the proposed rating strategy to assess the effect of these impacts. In addition, a neural network methodology was implemented on a simplified...

  5. Structural evaluation of the John A. Roebling Suspension Bridge : element level analysis.

    Science.gov (United States)

    2008-07-01

    The primary objective of the structural evaluation of the John A. Roebling Bridge is to determine the maximum allowable gross vehicle weight (GVW) that can be carried by the bridge deck structural elements such as the open steel grid deck, channels, ...

  6. Measurements in a container ship of wave-induced hull girder stresses in excess of design values

    DEFF Research Database (Denmark)

    Andersen, Ingrid Marie Vincent; Jensen, Jørgen Juncher

    2014-01-01

    This paper describes full-scale measurements of the wave-induced vertical bending moment amidships a 9400 TEU container carrier and focuses on the effect of the hydro-elastic high-frequency vibration on the extreme hogging wave bending moment. One extreme event, where the vertical wave-induced ho...... is quite significant. Finally, the hydro-elastic behaviour of the hull girder is assessed by simple approximations using the measured statistical properties and closed-form expressions and the agreement with the actual measurements is found to be good. © 2014 Elsevier Ltd....

  7. The effects of the pedestal/floor interface on the dynamic characteristics of the storage ring girder support assemblies

    International Nuclear Information System (INIS)

    Jendrzejczyk, J.A.; Chen, S.S.; Zhu, S.; Mangra, D.; Smith, R.K.

    1993-05-01

    To avoid unacceptable vibration of the storage ring quadrupoles, and to ensure that the established vibration criteria are satisfied, the philosophy from inception of the APS has been (1) to locate and design the machine to minimize motion of the storage ring basemat and, (2) following construction, to monitor machine operation and user experiments to ensure that vibration sources are not introduced. This report addresses the design of the storage ring girder support assemblies, and, specifically, the effect of the pedestal/floor interface on the dynamic characteristics (i.e., resonant frequencies, damping, and mode shape)

  8. Principles of Bridge Reliability

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Nowak, Andrzej S.

    The paper gives a brief introduction to the basic principles of structural reliability theory and its application to bridge engineering. Fundamental concepts like failure probability and reliability index are introduced. Ultimate as well as serviceability limit states for bridges are formulated......, and as an example the reliability profile and a sensitivity analyses for a corroded reinforced concrete bridge is shown....

  9. Research on Fluid Viscous Damper Parameters of Cable-Stayed Bridge in Northwest China

    Directory of Open Access Journals (Sweden)

    Xiongjun He

    2017-01-01

    Full Text Available To optimize the aseismic performance of nonlinear fluid viscous dampers (FVD of cable-stayed bridge in the highly seismic zone, Xigu Yellow River Bridge in northwest China is taken as an example. Nonlinear time-history analysis method is used to research on the relation among the internal forces, displacements, and damping parameters of the 650 tonnage FVD. The method of getting the minimum of binary functions is used to obtain the optimal parameters of FVD. Also, the 1 : 1 full-scale FVD model is made and used in the constitutive relation test. Then the test result of the damping parameters can be got by normal equation method. The optimized method to obtain the damping parameters is further verified. The results indicate that seismic response in key positions of the cable-stayed bridge can be reduced by installing longitudinal nonlinear FVD between the towers and girders if choosing reasonable damping parameters C and ξ. The optimal damping parameters can be calculated accurately by the proposed method of optimizing damping parameters of nonlinear FVD, and the constitutive relation test verifies the correctness of the optimization analysis method. Conclusions concerned can be applied to the design of nonlinear FVD for cable-stayed bridges.

  10. Technical features of steel structure construction by Kawasaki Steel; Kawasaki Seitetsu no kokozo gijutsu no tokucho

    Energy Technology Data Exchange (ETDEWEB)

    Kaneko, T.; Urata, I.; Okata, S. [Kawasaki Steel Corp., Tokyo (Japan)

    1996-03-01

    In the steel structure technology of Kawasaki Steel, the joint technique (e.g., welding) is added to them while developing or improving the products that meet the social needs as a material supplier. Moreover, the execution technique that manufactures materials or constructs them as an integrated structure, the structural analysis that conforms to the function and application of a structure, and the design technique on dynamic properties or durability such as earthquake resistance, fatigue, and corrosion resistance are synthetically expanded for engineering. In this paper, a building steel frame, non-residence building, bridge, and harbor structure as steel structure in the building and construction fields were described for each structure genre. The structural technology of a building steel frame is summarized to the products of pillar materials. An earthquake brace, using a dead soft steel, with high earthquake energy absorption capability and a damping wall were also developed. The design and execution technique of a large roof was systematized. The exchange technique of a road bridge RC floor and the technique of an unstiffened suspension bridge for pipeline were developed. A new technique was also developed for a suspension monorail track and offshore structure. 30 refs., 5 figs.

  11. Residual Strength Analysisof Asymmetrically Damaged Ship Hull GirderUsing Beam Finite Element Method

    Directory of Open Access Journals (Sweden)

    Muhammad Zubair Muis Alie

    2016-04-01

    Full Text Available The objective of the present study is to analyze the residual strength of asymmetrically damaged ship hull girder under longitudinal bending. Beam Finite Element Method isused for the assessment of the residual strength of two single hull bulk carriers (Ship B1 and Ship B4 and a three-cargo-hold model of a single-side Panamax Bulk Carrierin hogging and sagging conditions. The Smith’s  method  is  adopted  and  implemented  into  Beam  Finite  Element Method. An efficient solution procedure is applied; i.e. by assuming the cross section remains plane, the vertical bending moment is applied to the  cross section  and  three-cargo-hold  model. As a fundamental  case,  the  damage is simply  created  by removing the elements from the cross section, neglecting any welding residual stress and initial imperfection. Also no crack  extension  is considered.  The  result  obtained  by  Beam  Finite  Element  Method  so-called Beam-HULLST is compared to the progressive collapse analysis obtained by HULLST for the validation of the present work. Then, for the three-hold-model, the Beam-HULLST is used to investigate the effect of the rotation of the netral axisboth intact and damage condition taking the one and five frame spaces into account. 

  12. GPR signal analysis of post-tensioned prestressed concrete girder defects

    Science.gov (United States)

    Liu, Sixin; Weng, Changnian; Jiao, Pengfei; Wang, Fei; Fu, Lei; Meng, Xu; Lei, Linlin

    2013-06-01

    The accurate inspection of the duct condition in post-tensioned prestressed concrete (PPC) is an essential part of GPR concrete inspection. The purpose is to inspect the grouting condition of the ducts where the strands are located, to find out if there is a void in the ducts, and if any water exists. In order to investigate the radar image characteristics of different PPC duct defects, a number of model girders were manufactured. Three major ducts are included in our study: (1) well grouted and no void (normal condition); (2) the duct is half filled, and the void is filled by water or air; and (3) the duct is not filled at all, and the duct is water or air filled. The data corresponding to seven different situations are acquired and processed. It is found that the radar can detect the first interface in the duct, and the detailed structure inside the duct cannot be ‘seen’ from the images directly. Characteristic curves greatly help the interpretation. A completely void duct is the easiest to differentiate from the others. The signature for this situation is characterized by a strong and clear reflection interface which becomes weaker as the void is water filled. The normal condition shows the weakest reflection interface. As for the half void situation, the front scan shows a similar result to the normal condition whether it is water or air filled, and the back scan shows similar features to the completely void situation. The experiment and analysis is helpful and instructive for practical engineering inspection.

  13. Remote monitoring of fatigue-sensitive details on bridges : [part I and II].

    Science.gov (United States)

    2015-03-01

    Fatigue is one of the most critical problems for steel bridges as well as for any steel structures that needs : to be considered during design and operation. The objectives of this study are to explore monitoring : technologies, and to develop effect...

  14. Automatic Bridge Control System

    OpenAIRE

    M. Niraimathi; S.Sivakumar; R.Vigneshwaran; R.Vinothkumar; P.Babu

    2012-01-01

    Bridge vibration control is an important issue whose purpose is to extend the structural service life of bridges. Normally, the bridge is modeled as an elastic beam or plate subject to a moving vehicle. However, the moving truck on a bridge is a complicated problem that must still be researched. In this paper, wepropose a new method, to overcome the huge load in the bridge a load cell is used at the entry which will monitor the load continuously at both ends. To escape from the heavy water fl...

  15. Fatigue Assessment of Full-Scale Retrofitted Orthotropic Bridge Decks

    NARCIS (Netherlands)

    Teixeira De Freitas, S.; Kolstein, M.H.; Bijlaard, F.S.K.

    2017-01-01

    Full-scale fatigue tests were performed on two retrofitted orthotropic bridge decks (OBDs). The retrofitting systems consist of adding a second steel plate on the top of the existing deck. The aim is to reduce the stresses at the fatigue-sensitive details and therefore extend the fatigue life of

  16. The Selection of Bridge Materials Utilizing the Analytical Hierarchy Process

    Science.gov (United States)

    Robert L. Smith; Robert J. Bush; Daniel L. Schmoldt

    1997-01-01

    Effective decisions on the use of natural resources often require the input of many individuals. Determining how specific criteria affect the selection of materials can lead to better utilization of raw materials. Concrete, steel, and timber represent over 98% of the materials used for bridge construction in the United States. Highway officials must often consider...

  17. Solid Modeling and Finite Element Analysis of an Overhead Crane Bridge

    Directory of Open Access Journals (Sweden)

    C. Alkin

    2005-01-01

    Full Text Available The design of an overhead crane bridge with a double box girder has been investigated and a case study of a crane with 35 ton capacity and 13 m span length has been conducted. In the initial phase of the case study, conventional design calculations proposed by F. E. M. Rules and DIN standards were performed to verify the stress and deflection levels. The crane design was modeled using both solids and surfaces. Finite element meshes with 4-node tetrahedral and 4-node quadrilateral shell elements were generated from the solid and shell models, respectively. After a comparison of the finite element analyses, the conventional calculations and performance of the existing crane, the analysis with quadratic shell elements was found to give the most realistic results. As a result of this study, a design optimization method for an overhead crane is proposed. 

  18. Tool steels

    DEFF Research Database (Denmark)

    Højerslev, C.

    2001-01-01

    On designing a tool steel, its composition and heat treatment parameters are chosen to provide a hardened and tempered martensitic matrix in which carbides are evenly distributed. In this condition the matrix has an optimum combination of hardness andtoughness, the primary carbides provide...... resistance against abrasive wear and secondary carbides (if any) increase the resistance against plastic deformation. Tool steels are alloyed with carbide forming elements (Typically: vanadium, tungsten, molybdenumand chromium) furthermore some steel types contains cobalt. Addition of alloying elements...... serves primarily two purpose (i) to improve the hardenabillity and (ii) to provide harder and thermally more stable carbides than cementite. Assuming proper heattreatment, the properties of a tool steel depends on the which alloying elements are added and their respective concentrations....

  19. Long-Term Vibration Monitoring of the Effects of Temperature and Humidity on PC Girders with and without Fly Ash considering ASR Deterioration

    Directory of Open Access Journals (Sweden)

    Tuan Minh Ha

    2017-01-01

    Full Text Available Structural responses have been used as inputs in the evaluation procedures of civil structures for years. Apart from the degradation of a structure itself, changes in the environmental conditions affect its characteristics. For adequate maintenance, it is necessary to quantify the environment-induced changes and discriminate them from the effects due to damage. This study investigates the variation in the vibration responses of prestressed concrete (PC girders, which were deteriorated because of the alkali–silica reaction (ASR, concerning ambient temperature and humidity. Three PC girders were exposed to outdoor weather conditions outside the laboratory, one of which had a selected amount of fly ash in its mixture to mitigate the ASR. The girders were periodically vibration tested for one and a half years. It was found that when the temperature and humidity increased, the frequencies and damping ratios decreased in proportion. No apparent variation in the mode shapes could be identified. A finite element model was proposed for numerical verification, the results of which were in good agreement with the measured changes in the natural frequencies. Moreover, the different dynamic performances of the three specimens indicated that the fly ash significantly affected the vibrations of the PC girders under ASR deterioration.

  20. Numerical Simulation of Vertical Random Vibration of Train-Slab Track-Bridge Interaction System by PEM

    Directory of Open Access Journals (Sweden)

    Zhi-ping Zeng

    2014-01-01

    Full Text Available The paper describes the numerical simulation of the vertical random vibration of train-slab track-bridge interaction system by means of finite element method and pseudoexcitation method. Each vehicle is modeled as four-wheelset mass-spring-damper system with two-layer suspension systems. The rail, slab, and bridge girder are modeled by three-layer elastic Bernoulli-Euler beams connected with each other by spring and damper elements. The equations of motion for the entire system are derived according to energy principle. By regarding rail irregularity as a series of multipoint, different-phase random excitations, the random load vectors of the equations of motion are obtained by pseudoexcitation method. Taking a nine-span simply supported beam bridge traveled by a train consisting of 8 vehicles as an example, the vertical random vibration responses of the system are investigated. Firstly, the suitable number of discrete frequencies of rail irregularity is obtained by numerical experimentations. Secondly, the reliability and efficiency of pseudoexcitation method are verified through comparison with Monte Carlo method. Thirdly, the random vibration characteristics of train-slab track-bridge interaction system are analyzed by pseudoexcitation method. Finally, applying the 3σ rule for Gaussian stochastic process, the maximum responses of train-slab track-bridge interaction system with respect to various train speeds are studied.

  1. Drill pipe bridge plug

    International Nuclear Information System (INIS)

    Winslow, D.W.; Brisco, D.P.

    1991-01-01

    This patent describes a method of stopping flow of fluid up through a pipe bore of a pipe string in a well. It comprises: lowering a bridge plug apparatus on a work string into the pipe string to a position where the pipe bore is to be closed; communicating the pipe bore below a packer of the bridge plug apparatus through the bridge plug apparatus with a low pressure zone above the packer to permit the fluid to flow up through the bridge plug apparatus; engaging the bridge plug apparatus with an internal upset of the pipe string; while the fluid is flowing up through the bridge plug apparatus, pulling upward on the work string and the bridge plug apparatus and thereby sealing the packer against the pipe bore; isolating the pipe bore below the packer from the low pressure zone above the packer and thereby stopping flow of the fluid up through the pipe bore; disconnecting the work string from the bridge plug apparatus; and maintaining the bridge plug apparatus in engagement with the internal upset and sealed against the pipe bore due to an upward pressure differential applied to the bridge plug apparatus by the fluid contained therebelow

  2. Image Registration-Based Bolt Loosening Detection of Steel Joints

    Science.gov (United States)

    2018-01-01

    Self-loosening of bolts caused by repetitive loads and vibrations is one of the common defects that can weaken the structural integrity of bolted steel joints in civil structures. Many existing approaches for detecting loosening bolts are based on physical sensors and, hence, require extensive sensor deployment, which limit their abilities to cost-effectively detect loosened bolts in a large number of steel joints. Recently, computer vision-based structural health monitoring (SHM) technologies have demonstrated great potential for damage detection due to the benefits of being low cost, easy to deploy, and contactless. In this study, we propose a vision-based non-contact bolt loosening detection method that uses a consumer-grade digital camera. Two images of the monitored steel joint are first collected during different inspection periods and then aligned through two image registration processes. If the bolt experiences rotation between inspections, it will introduce differential features in the registration errors, serving as a good indicator for bolt loosening detection. The performance and robustness of this approach have been validated through a series of experimental investigations using three laboratory setups including a gusset plate on a cross frame, a column flange, and a girder web. The bolt loosening detection results are presented for easy interpretation such that informed decisions can be made about the detected loosened bolts. PMID:29597264

  3. Image Registration-Based Bolt Loosening Detection of Steel Joints.

    Science.gov (United States)

    Kong, Xiangxiong; Li, Jian

    2018-03-28

    Self-loosening of bolts caused by repetitive loads and vibrations is one of the common defects that can weaken the structural integrity of bolted steel joints in civil structures. Many existing approaches for detecting loosening bolts are based on physical sensors and, hence, require extensive sensor deployment, which limit their abilities to cost-effectively detect loosened bolts in a large number of steel joints. Recently, computer vision-based structural health monitoring (SHM) technologies have demonstrated great potential for damage detection due to the benefits of being low cost, easy to deploy, and contactless. In this study, we propose a vision-based non-contact bolt loosening detection method that uses a consumer-grade digital camera. Two images of the monitored steel joint are first collected during different inspection periods and then aligned through two image registration processes. If the bolt experiences rotation between inspections, it will introduce differential features in the registration errors, serving as a good indicator for bolt loosening detection. The performance and robustness of this approach have been validated through a series of experimental investigations using three laboratory setups including a gusset plate on a cross frame, a column flange, and a girder web. The bolt loosening detection results are presented for easy interpretation such that informed decisions can be made about the detected loosened bolts.

  4. Finite element modelling for fatigue stress analysis of large suspension bridges

    Science.gov (United States)

    Chan, Tommy H. T.; Guo, L.; Li, Z. X.

    2003-03-01

    Fatigue is an important failure mode for large suspension bridges under traffic loadings. However, large suspension bridges have so many attributes that it is difficult to analyze their fatigue damage using experimental measurement methods. Numerical simulation is a feasible method of studying such fatigue damage. In British standards, the finite element method is recommended as a rigorous method for steel bridge fatigue analysis. This paper aims at developing a finite element (FE) model of a large suspension steel bridge for fatigue stress analysis. As a case study, a FE model of the Tsing Ma Bridge is presented. The verification of the model is carried out with the help of the measured bridge modal characteristics and the online data measured by the structural health monitoring system installed on the bridge. The results show that the constructed FE model is efficient for bridge dynamic analysis. Global structural analyses using the developed FE model are presented to determine the components of the nominal stress generated by railway loadings and some typical highway loadings. The critical locations in the bridge main span are also identified with the numerical results of the global FE stress analysis. Local stress analysis of a typical weld connection is carried out to obtain the hot-spot stresses in the region. These results provide a basis for evaluating fatigue damage and predicting the remaining life of the bridge.

  5. Estimation of Tsunami Bore Forces on a Coastal Bridge Using an Extreme Learning Machine

    Directory of Open Access Journals (Sweden)

    Iman Mazinani

    2016-04-01

    Full Text Available This paper proposes a procedure to estimate tsunami wave forces on coastal bridges through a novel method based on Extreme Learning Machine (ELM and laboratory experiments. This research included three water depths, ten wave heights, and four bridge models with a variety of girders providing a total of 120 cases. The research was designed and adapted to estimate tsunami bore forces including horizontal force, vertical uplift and overturning moment on a coastal bridge. The experiments were carried out on 1:40 scaled concrete bridge models in a wave flume with dimensions of 24 m × 1.5 m × 2 m. Two six-axis load cells and four pressure sensors were installed to the base plate to measure forces. In the numerical procedure, estimation and prediction results of the ELM model were compared with Genetic Programming (GP and Artificial Neural Networks (ANNs models. The experimental results showed an improvement in predictive accuracy, and capability of generalization could be achieved by the ELM approach in comparison with GP and ANN. Moreover, results indicated that the ELM models developed could be used with confidence for further work on formulating novel model predictive strategy for tsunami bore forces on a coastal bridge. The experimental results indicated that the new algorithm could produce good generalization performance in most cases and could learn thousands of times faster than conventional popular learning algorithms. Therefore, it can be conclusively obtained that utilization of ELM is certainly developing as an alternative approach to estimate the tsunami bore forces on a coastal bridge.

  6. Bridge over troubled water?

    DEFF Research Database (Denmark)

    Svendsen, Gunnar Lind Haase; Nannestad, Peter; Svendsen, Gert Tinggaard

    2008-01-01

    The problem of integrating non-Western immigrants into Western welfare states is the focus of this paper. To address this issue, we suggest a social capital approach in which we apply the conceptual pair of bridging social capital (BR), which connects an individual to the broader social structure...... relationship between the levels of bridging and bonding capital, suggesting that bonding social capital in the immigrant group does not seem to impede the establishment of the bridging social capital needed for integration....

  7. Sustainable Bridge Infrastructure Procurement

    DEFF Research Database (Denmark)

    Safi, Mohammed; Du, Guangli; Simonsson, Peter

    2016-01-01

    The lack of a flexible but systematic approach for integrating lifecycle aspects into bridge investment decisions is a major obstacle hindering the procurement of sustainable bridge infrastructures. This paper addresses this obstacle by introducing a holistic approach that agencies could use...... to procure the most “sustainable” (lifecycle-efficient) bridge through a fair design-build (D-B) tendering process, considering all the main aspects: life-cycle cost (LCC), service life-span, aesthetic demands and environmental impacts (LCA)....

  8. Reliability Analysis of a Steel Frame

    Directory of Open Access Journals (Sweden)

    M. Sýkora

    2002-01-01

    Full Text Available A steel frame with haunches is designed according to Eurocodes. The frame is exposed to self-weight, snow, and wind actions. Lateral-torsional buckling appears to represent the most critical criterion, which is considered as a basis for the limit state function. In the reliability analysis, the probabilistic models proposed by the Joint Committee for Structural Safety (JCSS are used for basic variables. The uncertainty model coefficients take into account the inaccuracy of the resistance model for the haunched girder and the inaccuracy of the action effect model. The time invariant reliability analysis is based on Turkstra's rule for combinations of snow and wind actions. The time variant analysis describes snow and wind actions by jump processes with intermittencies. Assuming a 50-year lifetime, the obtained values of the reliability index b vary within the range from 3.95 up to 5.56. The cross-profile IPE 330 designed according to Eurocodes seems to be adequate. It appears that the time invariant reliability analysis based on Turkstra's rule provides considerably lower values of b than those obtained by the time variant analysis.

  9. The hepatic bridge.

    Science.gov (United States)

    Sugarbaker, Paul H

    2018-07-01

    The hepatic bridge forms a tunnel of liver parenchyma that may obscure peritoneal metastases associated with the round ligament. Visualization and then resection of nodules associated with this structure is necessary. The incidence of a hepatic bridge and the extent that it covered the round ligament was determined in consecutive patients. Extent of coverage of the round ligament by the hepatic bridge was determined: Class 1 indicates up to one-third of the round ligament obscured, Class 2 up to two-thirds and Class 3 more than two-thirds. In 102 patients in whom the round ligament of the liver could be completely visualized, 50 had a hepatic bridge. Class 1 was 22 (44%) of the bridges, Class 2 was 16 (32%) and Class 3 was 12 (24%). A hepatic bridge was more frequently present in 28 of 45 male patients (62%) vs. 22 of 57 female patients (38%). Approximately one-half of our patients having cytoreductive surgery for peritoneal metastases were observed to have a hepatic bridge. Up to 56% of these patients have Class 2 or 3 hepatic bridge and may require division of the hepatic bridge to completely visualize the contents of the tunnel created by this structure. Copyright © 2018 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

  10. Bridging the Gap

    DEFF Research Database (Denmark)

    Kramer Overgaard, Majken; Broeng, Jes; Jensen, Monika Luniewska

    Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures.......Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures....

  11. Vertical vibration control system for PC cable-stayed bridge during cantilever construction; Shuketa jogedo seishin sochi ni yoru haridashi sekoji no PC shachokyo no seishin

    Energy Technology Data Exchange (ETDEWEB)

    Oshio, M.; Nakano, R.; Niihara, Y.; Yano, K.; Takeda, T. [Kajima Corp., Tokyo (Japan)

    1995-12-20

    A PC cable-stayed bridge under extension construction having long span length may have long-cycle vibration generated because of wind. The vibration puts workers working on main girders into a state of seasick causing the workability to drop. Therefore, with an objective to reduce vibration occurring on the main girders during construction, discussions were given on application of an active type vertical vibration absorbing device. The vibration absorbing device is an active system that a weight is driven vertically by a hydraulic actuator. The device was developed with a target that damping ratio when a maximum extension is 120 m becomes three times that when no vibration is absorbed for a 5-span continuous PC cable-stayed bridge with a length of 675 m, a central span of 260 m, and a width of 11 m. A cage housing the weight is connected with the actuator at its top by using pins, and the weight is supported being suspended from the top of the actuator. Vibration is absorbed by utilizing reactive force generated when the weight is driven vertically by the hydraulic actuator. The hydraulic actuator contains a gas spring that supports the dead weight of the weight. Experiments have verified the effectiveness of the vertical vibration absorbing device. 4 refs., 12 figs., 3 tabs.

  12. Static and Dynamic Characteristics of a Long-Span Cable-Stayed Bridge with CFRP Cables

    Directory of Open Access Journals (Sweden)

    Xu Xie

    2014-06-01

    Full Text Available In this study, the scope of CFRP cables in cable-stayed bridges is studied by establishing a numerical model of a 1400-m span of the same. The mechanical properties and characteristics of CFRP stay cables and of a cable-stayed bridge with CFRP cables are here subjected to comprehensive analysis. The anomalies in the damping properties of free vibration, nonlinear parametric vibration and wind fluctuating vibration between steel cables and CFRP cables are determined. The structural stiffness, wind resistance and traffic vibration of the cable-stayed bridge with CFRP cables are also analyzed. It was found that the static performances of a cable-stayed bridge with CFRP cables and steel cables are basically the same. The natural frequencies of CFRP cables do not coincide with the major natural frequencies of the cable-stayed bridge, so the likelihood of CFRP cable-bridge coupling vibration is minuscule. For CFRP cables, the response amplitudes of both parametric vibration and wind fluctuating vibration are smaller than those of steel cables. It can be concluded from the research that the use of CFRP cables does not change the dynamic characteristics of the vehicle-bridge coupling vibration. Therefore, they can be used in long-span cable-stayed bridges with an excellent mechanical performance.

  13. Static and Dynamic Characteristics of a Long-Span Cable-Stayed Bridge with CFRP Cables.

    Science.gov (United States)

    Xie, Xu; Li, Xiaozhang; Shen, Yonggang

    2014-06-23

    In this study, the scope of CFRP cables in cable-stayed bridges is studied by establishing a numerical model of a 1400-m span of the same. The mechanical properties and characteristics of CFRP stay cables and of a cable-stayed bridge with CFRP cables are here subjected to comprehensive analysis. The anomalies in the damping properties of free vibration, nonlinear parametric vibration and wind fluctuating vibration between steel cables and CFRP cables are determined. The structural stiffness, wind resistance and traffic vibration of the cable-stayed bridge with CFRP cables are also analyzed. It was found that the static performances of a cable-stayed bridge with CFRP cables and steel cables are basically the same. The natural frequencies of CFRP cables do not coincide with the major natural frequencies of the cable-stayed bridge, so the likelihood of CFRP cable-bridge coupling vibration is minuscule. For CFRP cables, the response amplitudes of both parametric vibration and wind fluctuating vibration are smaller than those of steel cables. It can be concluded from the research that the use of CFRP cables does not change the dynamic characteristics of the vehicle-bridge coupling vibration. Therefore, they can be used in long-span cable-stayed bridges with an excellent mechanical performance.

  14. Influence of apparent wave velocity on seismic performance of a super-long-span triple-tower suspension bridge

    Directory of Open Access Journals (Sweden)

    Hao Wang

    2015-06-01

    Full Text Available As one of the main characteristics of seismic waves, apparent wave velocity has great influence on seismic responses of long-span suspension bridges. Understanding these influences is important for seismic design. In this article, the critical issues concerning the traveling wave effect analysis are first reviewed. Taizhou Bridge, the longest triple-tower suspension bridge in the world, is then taken as an example for this investigation. A three-dimensional finite element model of the bridge is established in ABAQUS, and the LANCZOS eigenvalue solver is employed to calculate the structural dynamic characteristics. Traveling wave effect on seismic responses of these long-span triple-tower suspension bridges is investigated. Envelopes of seismic shear force and moment in the longitudinal direction along the three towers, relative displacements between the towers and the girder, and reaction forces at the bottoms of the three towers under different apparent wave velocities are calculated and presented in detail. The results show that the effect of apparent wave velocity on the seismic responses of triple-tower suspension bridge fluctuates when the velocity is lower than 2000 m/s, and the effects turn stable when the velocity becomes larger. In addition, the effects of traveling wave are closely related to spectral characteristics and propagation direction of the seismic wave, and seismic responses of components closer to the source are relatively larger. Therefore, reliable estimation of the seismic input and apparent wave velocity according to the characteristics of the bridge site are significant for accurate prediction of seismic responses. This study provides critical reference for seismic analysis and design of long-span triple-tower suspension bridges.

  15. Bridge monitoring by interferometric deformation sensors

    Science.gov (United States)

    Inaudi, Daniele; Vurpillot, Samuel; Casanova, Nicoletta

    1996-09-01

    In many concrete bridges, the deformations are the most relevant parameter to be monitored in both short and long- terms. Strain monitoring gives only local information about the material behavior and too many such sensors would therefore be necessary to gain a complete understanding of the bridge behavior. We have found that fiber optic deformation sensors, with measurement bases of the order of one to a few meters, can give useful information both during the first days after concrete pouring and in the long term. In a first phase it is possible to monitor the thermal expansion due to the exothermic setting reaction and successively the thermal and drying shrinkages. Thanks to the long sensor basis, the detection of a crack traverse to the measurement region becomes probable and the evolution of cracks can therefore be followed with a reduced number of sensors. In the long-term it is possible to measure the geometric deformations and therefore the creeping of the bridge under static loads, especially under its own weight. In the past two years, our laboratory has installed hundreds of fiber optic deformation sensors in more than five concrete, composite steel-concrete, refurbished and enlarged bridges (road, highway and railway bridges). The measuring technique relies on low-coherence interferometry and offers a resolution down to a few microns even for long-term measurements. This contribution briefly discusses the measurement technique and then focuses on the development of a reliable sensor for direct concrete embedding and on the experimental results obtained on these bridges.

  16. Bridge health monitoring metrics : updating the bridge deficiency algorithm.

    Science.gov (United States)

    2009-10-01

    As part of its bridge management system, the Alabama Department of Transportation (ALDOT) must decide how best to spend its bridge replacement funds. In making these decisions, ALDOT managers currently use a deficiency algorithm to rank bridges that ...

  17. Long-term bridge performance high priority bridge performance issues.

    Science.gov (United States)

    2014-10-01

    Bridge performance is a multifaceted issue involving performance of materials and protective systems, : performance of individual components of the bridge, and performance of the structural system as a whole. The : Long-Term Bridge Performance (LTBP)...

  18. Steel alloys

    International Nuclear Information System (INIS)

    Bloom, E.E.; Stiegler, J.O.; Rowcliffe, A.F.; Leitnaker, J.M.

    1977-01-01

    The invention deals with a fuel element for fast breeder reactors. It consits essentially of a uranium oxide, nitride, or carbide or a mixture of these fuels with a plutonium or thorium oxide, nitride, or carbide. The fuel elements are coated with an austenitic stainless steel alloy. Inside the fuel elements, vacancies or small cavities are produced by neutron effects which causes the steel coating to swell. According to the invention, swelling is prevented by a modification of type 304, 316, 321, or 12 K 72HV commercial steels. They consist mainly of Fe, Cr, and Ni in a ratio determined by a temary diagram. They may also contain 1.8 to 2.3% by weight of Mo and a fraction of Si (0.7 to 2% by weight) and Ti(0.10 to 0.5% by weight) to prevent cavity formation. They are structurally modified by cold working. (IHOE) [de

  19. Design and Analysis of Collapsible Scissor Bridge

    Directory of Open Access Journals (Sweden)

    Biro Mohamad Nabil Aklif

    2018-01-01

    Full Text Available Collapsible scissor bridge is a portable bridge that can be deployed during emergency state to access remote areas that are affected by disaster such as flood. The objective of this research is to design a collapsible scissor bridge which is able to be transported by a 4x4 vehicle and to be deployed to connect remote areas. The design is done by using Solidworks and numerical analysis for structural strength is conducted via ANSYS. The research starts with parameters setting and modelling. Finite element analysis is conducted to analyze the strength by determining the safety factor of the bridge. Kutzbach equation is also analyzed to ensure that the mechanism is able to meet the targeted degree of motion. There are five major components of the scissor structure; pin, deck, cross shaft and deck shaft. The structure is controlled by hydraulic pump driven by a motor for the motions. Material used in simulation is A36 structural steel due to limited library in ANSYS. However, the proposed material is Fiber Reinforced Polymer (FRP composites as they have a high strength to weight ratio. FRP also tends to be corrosion resistance and this characteristic is useful in flooded area.

  20. Bridge Collapse Revealed By Multi-Temporal SAR Interferometry

    Science.gov (United States)

    Sousa, Joaquim; Bastos, Luisa

    2013-12-01

    On the night of March 4, 2001, the Hintze Ribeiro centennial Bridge, made of steel and concrete, collapsed in Entre-os-Rios (Northern Portugal), killing 59 people, including those in a bus and three cars that were attempting to reach the other side of the Douro River. It still remains the most serious road accident in the Portuguese history. In this work we do not intend to corroborate or contradict the official version of the accident causes, but only demonstrate the potential of Multi-Temporal Interferometric (MTI-InSAR) techniques for detection and monitoring of deformations in structures such as bridges, helping to prevent new catastrophic events. Based on the analysis of 57 ERS-1/2 covering the period from December 1992 to the fatality occurrence, we were able to detect significant movements (up to 20 mm/yr) in the section of the bridge that fell in the Douro River, obvious signs of the bridge instability.

  1. A Study of the Bolt Connection System for a Concrete Barrier of a Modular Bridge

    Directory of Open Access Journals (Sweden)

    Doo-Yong Cho

    2018-04-01

    Full Text Available Modular technology has been recently studied to reduce the construction periods in the field of bridge construction. However, this method is restricted to the pier, girder, and deck, which are the main members of a bridge, and incidental facilities such as concrete barriers have been rarely studied. Thus, in this study, the connection system of a concrete barrier for modular bridges was developed, and a static loading experiment was performed to verify the structural capacity of the proposed system. The variables of the experiment were the vertical and horizontal bolt connections and the construction method. The barrier and plate were fabricated using match casting methods in which nuts were first inserted into the plates rather than anchor bolts using the conservative method. Moreover, a comparison with the conventional in situ barrier was also performed. The experiments were conducted according to the AASHTO LRFD standard. Consequently, the specimen using the vertical bolt connection had a structural capacity that was equal to 85% of that of the conventional specimen and exhibited similar crack patterns compared with the conventional specimen. In the case of the horizontal bolt connection, the separation in the connection area occurred with the application of the initial load and this specimen exhibited a poor performance because of the increase in the separation distance with the application of the maximum load.

  2. Wind tunnel test on PC cable-stayed bridge; PC shachokyo no taifu seino shiken

    Energy Technology Data Exchange (ETDEWEB)

    Kubo, Y. [Kyushu Inst. of Technology, Kitakyushu (Japan). Faculty of Engineering

    1997-05-30

    This paper describes the wind tunnel test on a PC cable-stayed bridge. The aerodynamic force that acts on a building is represented by the drag that works in the wind direction, the lift that works perpendicularly to the wind direction, and the aerodynamic moment that causes rotation. In the measurement of wind load, a girder is partially extracted in the wind tunnel and set in a three-component balance, and the drag, lift, and aerodynamic moment are measured using a strain meter while blowing the wind. In a wind tunnel experiment, the similarity on Reynolds number, field number, rigidity, hydraulic force, structural attenuation, and reduced wind velocity is required. However, the wind velocity in the actual bridge uses the same air as that in an experiment. The similarity rule on the Reynolds is not thus satisfied. It is necessary to cause no self-excited vibration (galloping and flutter) as wind-resistant performance and suppress the eddy excitation to less than the allowable amplitude. Moreover, the three-dimensional experiment using an elastic model is conducted in addition to the two-dimensional experiment using a rigid model. In the three-dimensional experiment, various vibration modes that occur in the actual bridge appear. 12 refs., 15 figs.

  3. An Optimization Algorithm for the Design of an Irregularly-Shaped Bridge Based on the Orthogonal Test and Analytic Hierarchy Process

    Directory of Open Access Journals (Sweden)

    Hanbing Liu

    2016-11-01

    Full Text Available Irregularly-shaped bridges are usually adopted to connect the main bridge and ramps in urban overpasses, which are under significant flexion-torsion coupling effects and in complicated stress states. In irregular-shaped bridge design, the parameters such as ramp radius, bifurcation diaphragm stiffness, box girder height, and supporting condition could affect structural performance in different manners. In this paper, the influence of various parameters on three indices, including maximum stress, the stress variation coefficient, and the fundamental frequency of torsional vibration, is investigated and analyzed based on orthogonal test method. Through orthogonal analysis, the major influence parameters and corresponding optimal values for these indices are achieved. Combining with the analytic hierarchy process (AHP, the hierarchical structure model of the multi-indices orthogonal test is established and a comprehensive weight analysis method is proposed to reflect the parameter influence on overall mechanical properties of an irregularly-shaped bridge. Influence order and optimal values of parameters for overall mechanical properties are determined based on the weight of factors and levels calculated by the comprehensive weight analysis method. The results indicate that the comprehensive weight analysis method is superior to the overall balance method, which verifies the effectiveness and accuracy of the comprehensive weight analysis in the parameter optimization of the multi-indices orthogonal test for an irregularly-shaped bridge. Optimal parameters obtained in this paper can provide reference and guidance for parameter control in irregularly-shaped bridge design.

  4. Vertical gust response prediction of cable-stayed bridges in yawed wind; Shachokyo no shafu ni yoru enchoku gust oto no yosoku

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, S.; Nagamachi, K.; Kawai, Y. [Kawasaki Steel Corp., Tokyo (Japan); Kimura, K.; Fujino, Y. [The University of Tokyo, Tokyo (Japan). Faculty of Engineering; Tanaka, H.

    1996-03-01

    This paper outlines the vertical gust response analysis method in a yawed wind, gives an analytic example, and compares the experimental result with the analytic result to investigate the application of an analysis method and the validity of assumption and approximation. The vertical gust response to two cable-stayed bridges under construction in a yawed wind was predicted by applying assumption and approximation to the gust response prediction method in a yawed wind with the cantilever model having a plate cross-section manipulated. In this case, the wind velocity component perpendicular to the leading edge was defined as an effective wind velocity, and a bridge axis and the component perpendicular to a bridge axis were separately calculated in response. Moreover, some aerodynamic coefficients of a bridge girder cross-section were approximately obtained from the characteristics of the flat blades with same aspect ratio. The obtained analytic result was compared with the wind tunnel test result based on all bridge models. The result showed that the former almost coincides with the latter, the assumption and approximation of this time are verified in validity, and this analysis method can be used for cable-stayed bridges under construction. 10 refs., 7 figs., 2 tabs.

  5. Ultimate strength analysis of long-span cable-stayed bridges; Chodai chachokyo no shukyoku kyodo kaiseki to kyodo ni kansuru ichikosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Xie, X.; Yamaguchi, H. [Saitama Univ., Urawa (Japan)] Nagai, M. [Nagaoka Technical Coll., Niigata (Japan)

    1998-07-21

    Recently, span of cable-stayed bridges has been getting loner and longer, present situation is that cable-stayed bridges with span 600 to 800m class have been built inside and outside the country, and accurate determination of its ultimate strength has been an important problem statistically. However, concrete design method for evaluating load bearing stress of long-span cable-stayed bridge. Particularly of the main beam whose axial stress is dominating, has not been established so far. As for cable-stayed bridge, even for long-span, effect of plasticization of cross section on ultimate strength is severe because there is little effect of geometric nonlinearity and it is thought that accurate evaluation of ultimate strength only by elastic finite potential analysis is difficult. Accordingly, it is necessary to study the behavior by using combined nonlinear analysis considering the nonlinearity of the material in order to evaluate the safety and economy to long-span cable-stayed bridge. In this report, 3 dimensional analysis method was formularized taking into account the combine nonlinearity of multi-box girder and analysis program of ultimate strength behavior of long-span cable-stayed bridge was developed. 19 refs., 17 figs., 2 tabs.

  6. National Bridge Inventory System (NBI)

    Data.gov (United States)

    Department of Transportation — The NBI System is the collection of bridge inspection information and costs associated with bridge replacements of structurally deficient bridges on and off the NHS....

  7. Virtual Bridge Design Challenge

    Science.gov (United States)

    Mitts, Charles R.

    2013-01-01

    This design/problem-solving activity challenges students to design a replacement bridge for one that has been designated as either structurally deficient or functionally obsolete. The Aycock MS Technology/STEM Magnet Program Virtual Bridge Design Challenge is an authentic introduction to the engineering design process. It is a socially relevant…

  8. Bridge the Gap

    DEFF Research Database (Denmark)

    Marselis, Randi

    2017-01-01

    This article focuses on photo projects organised for teenage refugees by the Society for Humanistic Photography (Berlin, Germany). These projects, named Bridge the Gap I (2015), and Bridge the Gap II (2016), were carried out in Berlin and brought together teenagers with refugee and German...

  9. The floating water bridge

    International Nuclear Information System (INIS)

    Fuchs, Elmar C; Woisetschlaeger, Jakob; Gatterer, Karl; Maier, Eugen; Pecnik, Rene; Holler, Gert; Eisenkoelbl, Helmut

    2007-01-01

    When high voltage is applied to distilled water filled in two glass beakers which are in contact, a stable water connection forms spontaneously, giving the impression of a floating water bridge. A detailed experimental analysis reveals static and dynamic structures as well as heat and mass transfer through this bridge

  10. On-site bridge inspection with partial CT by 3.95Mev X-band linac source

    International Nuclear Information System (INIS)

    Wu, Wenjing; Zhu, Haito; Jin, Ming

    2012-01-01

    Since more and more bridges built several decades ago in Japan have become aged and dangerous, the non-destructive evaluation of those bridges is really an urgent problem. CT system with portable 3.95MeV linacs for bridge inspection is considered to work on-site, considering the law of Japanese radiation protection allows using linacs up to 4MeV outside radiation controlled area. The system would confirm the internal steel situation of bridges and analyze structural strain and stress with 3D model built from sectional imaging to evaluate load-bearing performance. The reconstruction process of bridge imaging is based on partial scanned data because bridge shape confines possible scanning angle to smaller than 180deg and a few translations. A small concrete sample with internal steel bars and attachment accessories is scanned in laboratory as preliminary work. (author)

  11. Advanced analysis and design for fire safety of steel structures

    CERN Document Server

    Li, Guoqiang

    2013-01-01

    Advanced Analysis and Design for Fire Safety of Steel Structures systematically presents the latest findings on behaviours of steel structural components in a fire, such as the catenary actions of restrained steel beams, the design methods for restrained steel columns, and the membrane actions of concrete floor slabs with steel decks. Using a systematic description of structural fire safety engineering principles, the authors illustrate the important difference between behaviours of an isolated structural element and the restrained component in a complete structure under fire conditions. The book will be an essential resource for structural engineers who wish to improve their understanding of steel buildings exposed to fires. It is also an ideal textbook for introductory courses in fire safety for master’s degree programs in structural engineering, and is excellent reading material for final-year undergraduate students in civil engineering and fire safety engineering. Furthermore, it successfully bridges th...

  12. Modern high strength QT, TM and duplex-stainless steels

    International Nuclear Information System (INIS)

    Bocquet, P.; Luxenburger, G.; Porter, D.; Ericsson, C.

    2003-01-01

    Pressure vessels are commonly manufactured with normalised steel grades with a yield strength up to 355 MPa or with austenitic stainless steels when corrosion as to be considered. From three decades, modern steels with higher mechanical properties - up to yield strength of 960 Mpa - are available and largely used for other applications where weight saving is of major importance as per off-shore, bridges, cranes, shipbuilding, line pipes.. The paper presents these modern steel's families - TMCP (Thermo Mechanically Controlled Process), QT (Quenched and Tempered) and Duplex (austeno-ferritic) stainless - in comparison with the normalised and austenitic steel grades. The following aspects are presented: the main mechanical properties (tensile and Charpy) as per the requirements of the standards for pressure equipment; some examples of use of these modern steels in the industry are given; the limitations of the forming conditions are considered; the weldability aspects and welds properties are developed; the interest of the PWHT (Post Weld Heat Treatment) is discussed. (orig.)

  13. Hegelian Steel

    DEFF Research Database (Denmark)

    Kjær, Poul F.

    2015-01-01

    Even in our globalized world the notion of national economies remain incredibly strong, just as a considerable part of the literature on transnational governance and globalization continue to rely on a zero-sum perspective concerning the relationship between the national and the transnational. De...... of the European steel industry....

  14. Assessment of the environmental effects associated with wooden bridges preserved with creosote, pentachlorophenol, or chromated copper arsenate

    Science.gov (United States)

    Kenneth M. Brooks

    Timber bridges provide an economical alternative to concrete and steel structures, particularly in rural areas with light to moderate vehicle traffic. Wooden components of these bridges are treated with chromated copper arsenate type C (CCA), pentachlorophenol, or creosote to prolong the life of the structure from a few years to many decades. This results in reduced...

  15. Expected damages of retrofitted bridges with RC jacketing

    Science.gov (United States)

    Montes, O.; Jara, J. M.; Jara, M.; Olmos, B. A.

    2015-07-01

    The bridge infrastructure in many countries of the world consists of medium span length structures built several decades ago and designed for very low seismic forces. Many of them are reinforced concrete structures that according to the current code regulations have to be rehabilitated to increase their seismic capacity. One way to reduce the vulnerability of the bridges is by using retrofitting techniques that increase the strength of the structure or by incorporating devices to reduce the seismic demand. One of the most common retrofit techniques of the bridges substructures is the use of RC jacketing; this research assesses the expected damages of seismically deficient medium length highway bridges retrofitted with reinforced concrete jacketing, by conducting a parametric study. We select a suite of twenty accelerograms of subduction earthquakes recorded close to the Pacific Coast in Mexico. The original structures consist of five 30 m span simple supported bridges with five pier heights of 5 m, 10 m, 15 m 20 and 25 m and the analyses include three different jacket thickness and three steel ratios. The bridges were subjected to the seismic records and non-linear time history analyses were carried out by using the OpenSEEs Plataform. Results allow selecting the reinforced concrete jacketing that better improves the expected seismic behavior of the bridge models.

  16. Expected damages of retrofitted bridges with RC jacketing

    International Nuclear Information System (INIS)

    Montes, O; Jara, J M; Jara, M; Olmos, B A

    2015-01-01

    The bridge infrastructure in many countries of the world consists of medium span length structures built several decades ago and designed for very low seismic forces. Many of them are reinforced concrete structures that according to the current code regulations have to be rehabilitated to increase their seismic capacity. One way to reduce the vulnerability of the bridges is by using retrofitting techniques that increase the strength of the structure or by incorporating devices to reduce the seismic demand. One of the most common retrofit techniques of the bridges substructures is the use of RC jacketing; this research assesses the expected damages of seismically deficient medium length highway bridges retrofitted with reinforced concrete jacketing, by conducting a parametric study. We select a suite of twenty accelerograms of subduction earthquakes recorded close to the Pacific Coast in Mexico. The original structures consist of five 30 m span simple supported bridges with five pier heights of 5 m, 10 m, 15 m 20 and 25 m and the analyses include three different jacket thickness and three steel ratios. The bridges were subjected to the seismic records and non-linear time history analyses were carried out by using the OpenSEEs Plataform. Results allow selecting the reinforced concrete jacketing that better improves the expected seismic behavior of the bridge models. (paper)

  17. The Corrosion of High Performance Steel in Adverse Environments

    International Nuclear Information System (INIS)

    Cook, Desmond C.

    2005-01-01

    The corrosion products that have formed on weathering steel bridges exposed to different weather conditions in the United States have been evaluated. They have been analyzed by spectroscopic techniques to determine the relationship between protective and non-protective rust coatings, and their relationship to the exposure conditions. Bridges constructed recently using High Performance Steel, as well as older bridges built with Type A588B weathering steel, were evaluated for corrosion performance of the rust coatings. In locations where the steel is subjected to regular wet-dry cycling, where the surface is wet for less than about 20% of the time, a protective patina starts to form after a few months exposure, and continues to an adherent, impervious coating after a decade. The protective patina is characterized by the formation of only goethite and lepidocrocite. The goethite makes up about 80% of the rust, and itself consists of a nanophase component, 40%, or infrequent drying cycles (regions close to waterways, fog or having high humidity), the weathering steel forms a rust coating that consists of a large amount of maghemite, and goethite that contains very little of the nanophase component. The rust coating ex-foliates from the steel and is not protective. Under exposure conditions in which chlorides are deposited onto the weathering steel surface (marine or de-icing salt locations), the protective patina also does not form. Instead, the rust coating consists of a large fraction of akaganeite that forms at the expense of the lepidocrocite and nanophase goethite. The bridges exposed to high chloride concentrations, 1.5 wt%, and therefore having no protective patina, have corrosion rates measured to be 6 times larger than expected for weathering steel with the protective patina

  18. Study of displacements of a bridge abutment using FEM

    Directory of Open Access Journals (Sweden)

    Wymysłowski Michał

    2016-06-01

    Full Text Available Steel sheet piles are often used to support excavations for bridge foundations. When they are left in place in the permanent works, they have the potential to increase foundation bearing capacity and reduce displacements; but their presence is not usually taken into account in foundation design. In this article, the results of finite element analysis of a typical abutment foundation, with and without cover of sheet piles, are presented to demonstrate these effects. The structure described is located over the Więceminka river in the town of Kołobrzeg, Poland. It is a single-span road bridge with reinforced concrete slab.

  19. Study of displacements of a bridge abutment using FEM

    Science.gov (United States)

    Wymysłowski, Michał; Kurałowicz, Zygmunt

    2016-06-01

    Steel sheet piles are often used to support excavations for bridge foundations. When they are left in place in the permanent works, they have the potential to increase foundation bearing capacity and reduce displacements; but their presence is not usually taken into account in foundation design. In this article, the results of finite element analysis of a typical abutment foundation, with and without cover of sheet piles, are presented to demonstrate these effects. The structure described is located over the Więceminka river in the town of Kołobrzeg, Poland. It is a single-span road bridge with reinforced concrete slab.

  20. FEATURES OF DESIGN OF TIED-ARCH BRIDGES WITH FLEXIBLE INCLINED SUSPENSION HANGERS

    Directory of Open Access Journals (Sweden)

    V. O. Samosvat

    2017-10-01

    Full Text Available Purpose. Investigation and analysis of the hanger arrangement and the structural stability of a Network arch bridge – a tied-arch bridge with inclined hangers that cross each other at least twice. It is also necessary to make a comparative analysis with other types of hanger arrangements. Methodology. The authors in their research investigated a large number of parameters to determine their influence in the force distribution in the arch. Eventually they determined optimal values for all parameters. These optimal values allowed developing a design guide that leads to optimal arch design. When solving this problem, the authors used three-dimensional finite element models and the objective was to determine the most suitable solution for a road bridge, with a span of 100 meters, consisting of two inclined steel arches, located on a road with two traffic lanes, subjected to medium traffic. The virtual prototype of the model is performed by finite element simulator Midas Civil. Findings. In this study, for the bridge deck, a concrete tie appears to be the best solution considering the structural behavior of network arches, but economic advantages caused by easier erection may lead to steel or a composite bridge deck as better alternatives. Design requirements and local conditions of each particular bridge project will decide the most economic deck design.Originality. To ensure passenger comfort and the stability and continuity of the track, deformations of bridges are constricted. A network arch is a stiff structure with small deflections and therefore suitable to comply with such demands even for high speed railway traffic.
A network arch bridge with a concrete tie usually saves more than half the steel required for tied arches with vertical hangers and concrete ties. Practical value. Following the study design advice given in this article leads to savings of about 60 % of structural steel compared with conventional tied arch bridges with