The 20 papers in this report deal with the following areas: determination of layer moduli using a falling weight deflectometer; evaluation of effect of uncrushed base layers on pavement performance; the effect of contact area shape and pressure distribution on multilayer systems response; sensitivity analysis of selected backcalculation procedures; performance of a full-scale pavement design experiment in Jamaica; subsealing and load-transfer restoration; development of a demonstration prototype expert system for concrete pavement evaluation; numerical assessment of pavement test sections; development of a distress index and rehabilitation criteria for continuously reinforced concrete pavements using discriminant analysis; a mechanistic model for thermally induced reflection cracking of portland cement concrete pavement with reinforced asphalt concrete overlay; New Mexico study of interlayers used in reflective crack control; status of the South Dakota profilometer; incorporating the effects of tread pattern in a dynamic tire excitation mechanism; external methods for evaluating shock absorbers for road-roughness measurements; factor analysis of pavement distresses for surface condition predictions; development of a utility evaluation for nondestructive-testing equipment used on asphalt-concrete pavements; estimating the life of asphalt overlays using long-term pavement performance data; present serviceability-roughness correlations using rating panel data; video image distress analysis technique for Idaho transportation department pavement-management system; acceptability of shock absorbers for road roughness-measuring trailers.

The 12 papers in the report deal with the following areas: procedures for estimation of asphalt-concrete pavement moduli at in-situ temperatures; stress caused by temperature gradient in portland-cement concrete pavements; characterizing temperature effects for pavement analysis and design; temperature response of concrete pavements; an examination of environmental versus load effects on pavements; moisture in portland-cement concrete; effect of rainfall on the performance of continuously reinforced concrete pavements in Texas; effect of moisture on the structural performance of a crushed-limestone road base; water-induced distress in flexible pavement in a wet tropical climate; an evaluation of design high-water clearances for pavements; economic impact of pavement subsurface drainage; use of open-graded, free-draining layers in pavement systems; a national synthesis report.

Needs have increased on pavement with good durability, in addition to pavement in which asphalt pavement and concrete pavement having directly-opposed characteristics are compounded to utilize the characteristics of the both pavements, being greater convenience in construction and sooner reopening of traffic. Pavement attempting to achieve compounding both pavements in the aspect of pavement construction is the composite pavement using concrete pavement in the basic layer and asphalt pavement on the surface layer. Pavement attempting the same objective in the aspect of materials is the semi-bending pavement which utilizes compositely the bending property of the asphalt pavement and the durability of the concrete pavement. On the other hand, there is a type of pavement in which cement and asphalt emulsion are compounded. The asphalt emulsion disperses asphalt in water by means of emulsion, and is a material that can be used at normal temperatures, and can suppress generation of CO2 and save energy. This paper presents the present situation of inorganic-organic composite materials for pavement. 14 refs., 10 figs., 8 tabs.

A wavelet-based pavement distress detection and evaluation method is proposed. This method consists of two main parts, real-time processing for distress detection and offline processing for distress evaluation. The real-time processing part includes wavelet transform, distress detection and isolation, and image compression and noise reduction. When a pavement image is decomposed into different frequency subbands by wavelet transform, the distresses, which are usually irregular in shape, appear as high-amplitude wavelet coefficients in the high-frequency details subbands, while the background appears in the low-frequency approximation subband. Two statistical parameters, high-amplitude wavelet coefficient percentage (HAWCP) and high-frequency energy percentage (HFEP), are established and used as criteria for real-time distress detection and distress image isolation. For compression of isolated distress images, a modified EZW (Embedded Zerotrees of Wavelet coding) is developed, which can simultaneously compress the images and reduce the noise. The compressed data are saved to the hard drive for further analysis and evaluation. The offline processing includes distress classification, distress quantification, and reconstruction of the original image for distress segmentation, distress mapping, and maintenance decision-making. The compressed data are first loaded and decoded to obtain wavelet coefficients. Then Radon transform is then applied and the parameters related to the peaks in the Radon domain are used for distress classification. For distress quantification, a norm is defined that can be used as an index for evaluating the severity and extent of the distress. Compared to visual or manual inspection, the proposed method has the advantages of being objective, high-speed, safe, automated, and applicable to different types of pavements and distresses.

In many countries road network ages while road traffic and maintenance costs increase. Nowadays, thousand and thousand kilometers of roads are each year submitted to surface distress survey. They generally lean on pavement surface imaging measurement techniques, mainly in the visible spectrum, coupled with visual inspection or image processing detection of emergent distresses. Nevertheless, optimisation of maintenance works and costs requires an early detection of defects within the pavement structure when they still are hidden from surface. Accordingly, alternative measurement techniques for pavement monitoring are currently under investigation (seismic methods, step frequency radar). On the other hand, strengthening or retrofitting of reinforced concrete structures by externally bonded Fiber Reinforced Polymer (FRP) systems is now a commonly accepted and widespread technique. However, the use of bonding techniques always implies following rigorous installing procedures. To ensure the durability and long-term performance of the FRP reinforcements, conformance checking through an in situ auscultation of the bonded FRP systems is then highly suitable. The quality-control program should involve a set of adequate inspections and tests. Visual inspection and acoustic sounding (hammer tap) are commonly used to detect delaminations (disbonds) but are unable to provide sufficient information about the depth (in case of multilayered composite) and width of debonded areas. Consequently, rapid and efficient inspection methods are also required. Among the non destructive methods under study, active infrared thermography was investigated both for pavement and civil engineering structures through experiments in laboratory and numerical simulations, because of its ability to be also used on field. Pulse Thermography (PT), Pulse Phase Thermography (PPT) and Principal Component Thermography (PCT) approaches have been tested onto pavement samples and CFRP bonding on concrete samples in laboratory. In parallel numerical simulations have been used to generate a set of time sequence of thermal maps for simulated samples with and without subsurface defect. Using this set of experimental and simulated data different approaches (thermal contrast, FFT analysis, polynomial interpolation, singular value decomposition…) for defect location have been studied and compared. Defect depth retrieval was also studied on such data using different thermal model coupled to a direct or an inverse approach. Trials were conducted both with an uncooled and cooled infrared camera with different measurement performances. Results obtained will be discussed and analysed in the paper we plan to present. Finally, combining numerical simulations and experiments allows us discussing on the sensitivity influence of the infrared camera used to detect subsurface defects.

The majority of Brazilian roadpavements consistsof thin pavement structures unable to resist the damage caused by heavy loads and an increasing traffic demand. The main structural distress modes found in Brazilians asphalt layers is fatigue cracking. One of the prom-ising techniques to improve the p...

The 10 papers in the report deal with the following areas: South Dakota profilometer; development of a data-acquisition method for noncontact pavement macrotexture measurement; traction of an aircraft tire on grooved and porous asphaltic concrete; holes in the pavement-an assessment of their influence on safety; effect of pavement type and condition on the fuel consumption of vehicles; traction loss of a suspended tire on a sinusoidal road; effect of vehicle and driver characteristics on the psychological evaluation of road roughness; correlation of subjective panel ratings of pavement ride quality with profilometer-derived measures of pavement roughness; microprocessor-based noncontact distance measuring control system; and, representation of pavement-surface topography in predicting runoff depths and hydroplaning potential.

Experimental and analytical investigations were conducted to evaluate the effects of dowel misalignment on the joint opening behaviour and associated distresses in concrete pavement joints. The experimental investigations focused on pavement specimens with one or two misaligned dowel bars at the joints, and the results included the pull-out force-joint opening responses and the observations of damage (spalling, cracking, etc.). Numerical models of the pavement specimens were developed to gain additional insight into the behaviour, 3D stresses and strains, and localised damage associated with the misaligned dowel bars. These models accounted for (a) concrete inelasticity in compression and cracking in tension and (b) the longitudinal bond and the transverse interaction between the dowel and...

Tazawa et al studied influences of particle size of aggregate and kinds of filler aiming at applying acrylic resin containing resin concrete on drainage pavement. Minemura et al reported that the compounding study results of high porous concrete for vehicles of L traffic level, and experimental results applying it on manage road in a dam. Shirai et al measured daylight absorption and temperature changing of each simulation plates of porous concrete pavement, normal concrete pavement and asphalt pavement. Kamiya et al discussed the removing ability of NOx in the case of using titanium oxide in surface mortar of interlocking block and in injecting materials of semi-bending pavement. Okamoto et al proposed a method that exerts management by actual torque instead of a traditional method that sets the vibration number of a vibrator corresponding to slump for the slip form construction of a concrete barrier. (NEDO)

The performance of two open-friction courses (OFC) having 1/2 in. and 1/4 in. maximum-sized aggregates - and their adjacent conventional New York State 1A top-course (control) is documented over the final 4 years of their 7-year design lives. The pavements were evaluated by analysis of mix properties and surface performance. The physical properties examined by means of extracted pavement cores were aggregate gradation, binder penetration and viscosities, and void content. Testing of frictional performance, rut depths, microtecture and macrotexture, rideability, and cracking were used to evaluate the pavement's surface performance.

This paper investigates influence of pavement macrotexture on paved road PM10 emissions. This study was conducted on different paved roadway types (local, collector and minor arterial) in the Las Vegas Valley, Nevada. Pavement macrotexture was measured using the ASTM E 965 sand patch method and the Digital Surface Roughness Meter (DSRM). A controlled constant soil loading with known PM10 fraction was applied to cleaned road surfaces. The Desert Research Institutes (DRI) Mini-PI-SWERL (Portable In-Situ Wind ERosion Lab) was used to estimate PM10 mass emissions and cumulative mass emitted from pavement surfaces. PM10 mass emissions using controlled applied soil loadings generally declined with increasing pavement macrotexture at all applied shear levels. The relationships were statistically ...

The papers in this volume, which deal with asphalt pavement surfaces and asphalt mixtures, should be of interest to state and local construction, design, materials, and research engineers as well as contractors and material producers. The papers in Part 1 include discussions of pavement smoothness specifications and skidding characteristics. The first four papers in Part 2 were submitted in response to a call for papers for a session at the 75th Annual Meeting of the Transportation Research Board on low-temperature properties of hot-mix asphalt. The next eight are on the influence of volumetric and strength properties on the performance of hot-mix asphalt. In the following three papers, the topics covered are the complex modulus of asphalt concrete, cold in-place asphalt recycling, and polymer modification of asphalt pavements in Ontario. The last two papers were presented in a session on relationship of materials characterization to accelerated pavement performance testing.

Pavement structures on poor soil sub grades show early distresses causing the premature failure of the pavement. Clayey soils usually have the potential to demonstrate undesirable engineering behavior, such as low bearing capacity, high shrinkage and swell characteristics and high moisture susceptibility. Stabilization of these soils is a usual practice for improving the strength. This study reports the improvement in the strength of a locally available cohesive soil by addition of both fly ash and lime. Analysis using X-ray diffraction, scanning electron microscopy, coupled with energy dispersive spectroscopy, thermal gravimetric analysis, zeta potential and pH value test was carried out in order to elucidate the stabilization mechanism. The micro level analysis confirmed the breaking of ...

The progressive urbanization of US arid and semi-arid southwestern territories has transformed undeveloped aridlands into dynamic, radially expanding metropolitan centers. As these mature, infill development further reduces undeveloped area, inversely coupling surface imperviousness to infiltration rates, with a subsequent increase in runoff generation. Intensified runoff carries undesirable environmental consequences, magnifying urban flooding events and concentrations, transport, and propagation of contaminants. Pervious pavements offer one potential solution for decreased urban infiltration. At present, the application potential of pervious pavements as an effective urban infiltration management tool exceeds its exploitation. While entirely eliminating urban Total Impervious Area is not a feasible solution, pervious pavements significantly reduce Effective Impervious Area at costs competitive with traditional Best Management Practices. Previous research into pervious pavements has largely consisted of laboratory prototypes or small-scale field experiments, with a heavy bias towards parking lots. In this study we explore the effectiveness of pervious pavements in increasing infiltration, thus decreasing runoff volume during summer monsoonal and winter convective rainfall events in an 8 ha residential catchment in Scottsdale, Arizona. Analysis focuses on the interaction dynamics between surface area of pervious pavement application and its net effect on runoff response at the catchment level. Hydrological response was modeled using MAHLERAN (Model for Assessing Hillslope-Landscape Erosion, Runoff and Nutrients), a spatially explicit, event-based model, parameterized at a spatial resolution of 0.25 sq m. Data for model parameterization was obtained from analysis of aerial imagery and field-based monitoring of surface properties. The model was tested against measurements of flow at the catchment outlet for multiple rainfall events with total event rainfall ranging from 5 mm to 25 mm. Model testing shows total event discharge simulated well, although low Nash-Sutcliffe coefficients for events indicate a poor fit between the shape and timing of the modeled and monitored hydrograph, which we attribute to poor characterization of friction factors in urban catchments. Scenario-based model analysis tested catchment response to substitution of pervious for conventional pavement by percent and pavement-function scenarios. Results are consistent with previous findings in that short duration-high intensity storms trigger threshold infiltration capacity, past which pervious pavement damping of runoff volume levels off, approaching conventional levels. However at the modeled catchment scale, this initial damping represents a significant reduction in volume, peak flow velocity, and contaminant loading potential. Urban surface drainage networks concentrate and channel flow along roads: the capacity of pervious pavements to simultaneously increase infiltration directly at location of greatest runoff and mitigate inflow effects from remote points has compelling potential as a hydrologic and urban systems engineering tool.

Ground Penetrating Radar (GPR) is a Non Destructive Testing (NDT) technique that has been developed and improved upon over the past 30 years. The technique is frequently utilized in order to evaluate and assess pavement structures. GPR, for pavement evaluation purposes, can be described as a remote sensing system that emits a short pulse, of electromagnetic energy, into the pavement, with a central frequency varying from 10 MHz up to 2.5GHz. The two most commonly utilized setups are air-coupled and ground-coupled antenna systems. For air-coupled systems, the antennas are suspended above the pavement surface and can operate at normal traffic speeds (up to ~ 80 Km/h). The major drawback of the air-coupled antenna is that penetration depth is limited. On the other hand, for ground-coupled systems the antennas are in direct contact with the pavement surface, providing for better signal penetration into the pavement structure; however ground coupled systems can achieve only limited operational speeds. As a generalized rule, increasing the GPR central operating frequency, increases the investigation resolution, while decreasing the overall depth of investigation In the light of the above, air-coupled systems have become increasingly popular for the evaluation of the part of the pavement structure, especially for the asphalt layers, while ground-coupled systems are utilized mostly in order to gather information from the entire pavement structure (up to ~ 3 m depth). The majority of GPR pavement studies are carried out with air-coupled horn antennas, as they can be implemented at driving speeds without need for road closures. For instance, the 1 GHz air-coupled horn antenna is commonly used for the estimation of pavement layer thickness. However signals generated by horn antenna systems must have sufficient quality to allow the performance of automated signal processing and qualitative data analysis, especially when pavement data more sensitive to the analysis parameters, such voids or moisture, is concerned. The implementation of the horn antenna method is dependent upon, amongst others, the resolution of the antenna in use. The present research work investigates the application of the GPR sensor technique to assess voids within the asphalt layers, with a focus on the air-coupled antenna penetration depth and resolution. For this purpose the dielectric properties of asphalt layer materials were estimated and related voids contents were evaluated based on data collected by an air-coupled GPR system, operating at a 1 GHz and alternatively a 2 GHz central frequency. The collected data is analyzed comparatively for the two antennas. Comparison results indicate differences between the voids determined from the 1 GHz and 2GHz antennas. These differences are further analyzed and evaluated for pavement quality control purposes. The indication of a relationship between the measured voids is also evaluated, while ground truth data is used for the validation of the GPR data analysis results. The above is presented and discussed thoroughly with the aim to assist pavement quality assurance systems

Increasing the solar reflectance of the urban surface reduce its solar heat gain, lowers its temperatures, and decreases its outflow of thermal infrared radiation into the atmosphere. This process of 'negative radiative forcing' can help counter the effects of global warming. In addition, cool roofs reduce cooling-energy use in air conditioned buildings and increase comfort in unconditioned buildings; and cool roofs and cool pavements mitigate summer urban heat islands, improving outdoor air quality and comfort. Installing cool roofs and cool pavements in cities worldwide is a compelling win-win-win activity that can be undertaken immediately, outside of international negotiations to cap CO{sub 2} emissions. We propose an international campaign to use solar reflective materials when roofs and pavements are built or resurfaced in temperate and tropical regions.

In many developing countries, where resources are at premium, thin asphalt layers or chip seals are widely used to provide a durable all weather pavement surfacing. In such pavements the role of granular layers is very important in the general performance of the structure. Pavement designs in these countries are empirical in nature and rely on simple input parameters like California Bearing Ratio (CBR) values. Although widely applicable the traditional CBR test does not provide the mechanical properties such as resilient and permanent deformation characteristics of granular road materials. This paper documents the characterization technique developed to determine the mechanical behavior of granular (sub-) base materials based on CBR test using repeated load cycles. The confining pressure d...

The 10 papers in the report deal with the following areas: Investigation of segregation of asphalt mixtures in the State of Georgia; Evaluation of a thin-lift nuclear density gauge; Effect of compaction on asphalt concrete performance; Effects of field control of filler contents and compaction on asphalt mix properties; Expert system for diagnosing hot-mix asphalt segregation; Enhancing the bond of emulsion-based seal coats with antistripping agents; Research program for predicting the frictional characteristics of seal-coat pavement surfaces; Performance of 18 bituminous test sections on a major urban freeway during 11 years of service; Asphalt overlays of concrete pavements: Cast studies in Arkansas; Asphalt concrete mixtures as related to pavement rutting: case studies.

In most structural pavement design methods, strains and stresses in the layers are calculated with multi-layer programs based on the Burmister model using the linear elastic theory. Burmister defined loads as a constant pressure applied on a circular surface. New technology for measuring t...

Walking on wet pavement during or after heavy rain results in wet shoes, and often, wet feet. We describe a peculiar transport process associated with walking on wet surfaces which results in the vamps, and frequently, the insides, of shoes getting wet. We discuss details of this process and compare experimental results with simple model predictions. Strategies for keeping feet dry will be considered.

Over the past several years, the Texas Department of Transportation (TxDOT) adopted the use of porous or permeable friction course (PFC) mixtures as a thin asphalt pavement surface layer to provide safety and environmental benefits. This type of mixture i...

The British pendulum tester is commonly used for the measurement of skid resistance of pavement surfaces. Although it is widely suggested that the measurement is largely governed by the microtexture of the pavement surface, experience has shown that the macrotexture can also affect the measurements. It can also lead to misleading results on coarse-textured test surfaces. This paper reports the findings of a study conducted to examine the effect of macrotexture on the British pendulum measurements. The study employed a three-dimensional finite element model to analyze the behavior of the test device. The results of the analysis showed significant variations of test results on sparsely spaced textured surfaces, especially those that exhibited discontinuities. The results demonstrated that the edge impacts between coarse-textured surface features and the pendulum slider would give rise to unreliable test measurements.   

A pavement condition survey was performed at Edwards Air Force Base, California, in August 1989 for the purpose of determining the pavement condition index of the airfield features and for performing the initial implementation of the PAVER pavement manage...

A flexible test pavement, instrumented to measure stresses and strains in the three primary axes with the upper 400 mm of the subgrade, has been constructed and load tested in the Danish Road Testing Machine (RTM). One objective of this research, which is part of the International Pavement Subgrade Performance Study, is to develop an improved mechanistic subgrade failure criterion.Simulated traffic loads were applied between June and December 1997 by a dual tyre loading cart within a climate chamber maintained at a constant temperature. Three load levels (40 kN, 50 kN and 60 kN) were applied. In all three test series, 50000 load repetitions were applied at each load level, and the test chamber temperature was maintained at approximately 25 degree C.Instruments installed in the test pavement included: Strain measuring sensors (LVDT Soil Strain Deformation Transducers and Asphalt Strain Gauges), Soil Pressure Cells, Thermistors and Pore Pressure Sensors. Routine monitoring of instrument responses and surface profiles with a Profilometer and FWD/LWD structural testing were undertaken at regular intervals during the construction and load testing programmes.This paper compares various structural analysis methods used for the RTM test pavement with data from FWD testing undertaken after the construction and loading programmes. Multilayer linear elastic forward and backcalculation methods, a finite element program and MS Excel spreadsheet based methods are compared.

A thin layer of porous asphalt is commonly overlain on regular impermeable pavement to reduce splash and spray and improve visibility in wet weather. The porous layer often has a large hydraulic conductivity (>1cm/s) to encourage infiltration and drainage and therefore contains runoff when the rainfall intensity is low. However, under high rainfall intensity, the layer’s capacity is exceeded and drainage occurs both within and on top of the porous pavement. The problem is analogous to hill-slope hydrology of a thin aquifer where infiltration occurs rapidly and sheet flow is generated only when the aquifer is full. Common roadway features such as slope transitions and curvature make the drainage two-dimensional. A computer model was developed to study this coupled, unsteady process. The porous layer is modeled using the Boussinesq equation. The diffusion wave model is used for sheet flow over the pavement surface. This presentation summarizes the model’s development, shows that model results compare favorably to field measurements, and gives a case study in which the porous layer reduces the maximum sheet flow depth by 25% compared to conventional pavement.

...information such as roughness, distress, rutting, and surface friction; Bridge features such as deck width, under/over-clearance...of structural elements such as girders, joints, railings, bearings, abutments, and piers; and information on the...

Ground-penetrating radar (GPR) has been used to study the variations in the depth of the frost table throughout a complete thaw-freeze season in Kangerlussuaq Airport, western Greenland. In autumn 2000, three test areas were painted white on the parking area of the airport in order to reduce further development of depressions in the asphalt pavement. One of these areas has been used in the GPR investigations to compare the variations of the frost table underneath a normal dark asphalt surface to that below a more reflective surface. The GPR results have shown a clear correlation between the use of the reflective surface and a reduced depth to frost table. In late summer the difference in the depths to the frost table is approximately 0.9 m. The results should promote the interest in the development and use of light colored pavement materials in order to reduce the effect of a warming climate on arctic infrastructures.

Rejuvenators are products designed to restore original properties to aged (oxidized) asphalt binders by restoring the original ratio of asphaltenes to maltenes. These products are used to retard the loss of surface fines and to reduce the formation of additional cracks; however, for a rejuvenator to be successful, it must penetrate the pavement surface. Besides, application of a rejuvenator will also reduce the skid resistance of the pavement, which may be significant for runways or other areas where high aircraft speeds are likely to occur. To solve this, in [1], these rejuvenators were encapsulated and mixed in asphalt concrete. The idea is that once the stress in the capsules reaches a certain threshold, the particles break and the rejuvenator is released. This research focuses on the p...

Since the heat capacity of road surfaces on steel deck bridges is small, they have more amount of frost and snow cover in winter, resulting in frequent traffic accidents. This paper describes the prevention of road surfaces from freezing with heat storage materials. Since temperature of road decks is lower than those beneath bridges and of bulkheads due to radiation cooling from midnight to early morning, they are heated from the surroundings. Accordingly, insulation beneath the steel deck accelerates the freezing of road surface on bridges. To prevent frost and reduce snow cover in 2 cm, phase change insulator having 3 to 5degC solidifying and melting point was set in the pavement on the steel deck. Using this insulator, temperature of the steel deck was higher than that of concrete deck in the case of radiation cooling of pavement surface up to -3degC. The maximum temperature of steel deck pavement can be predicted from the global solar radiation and the maximum atmospheric temperature. When it was more than 14degC, the liquefied insulator could store the latent heat. The insulator could save solar energy completely in daytime on the 19 following mornings with radiation cooling during one season at Fukui City. In FY 1996, this method was applied to the curve interval of steel deck bridge following to the concrete deck road at Fukui City. 13 refs., 30 figs., 2 tabs.

This synthesis will be of interest to pavement designers, maintenance engineers, and others responsible for the management of highway pavements. Information is presented on pavement management systems - the established, documented procedures used to treat all activities involved in providing and sustaining pavements in an acceptable condition. As highway agencies focus more attention on maintenance and rehabilitation of highway networks, the use of some form of a pavement management system becomes increasingly important. This report of the Transportation Research Board describes the features, applicability, and used of a pavement management system and recommends five general steps for implementing a new pavement management system or improving an existing system.

Abstract in portuguese Monitorar a condição de uso de toda a extensão das rodovias brasileiras é tarefa dispendiosa e demorada. Este trabalho trata de novas técnicas que permitem o levantamento da condição da superfície dos pavimentos rodoviários de forma ágil utilizando imagens hiperespectrais de sensor digital aeroembarcado. Nos últimos anos, um número crescente de imagens de alta resolução espacial tem surgido no mercado mundial com o aparecimento dos novos satélites e sensore (more) s aeroembarcados de sensoriamento remoto. Propõe-se uma metodologia para identificação dos pavimentos asfálticos e classificação das principais ocorrências dos defeitos na superfície do pavimento. A primeira etapa da metodologia é a identificação da superfície asfáltica na imagem, utilizando uma classificação híbrida baseada inicialmente em pixel e depois refinada por objetos. A segunda etapa da metodologia é a identificação e classificação das ocorrências dos principais defeitos nos pavimentos flexíveis que são observáveis nas imagens de alta resolução espacial. Esta última etapa faz uso intensivo das novas técnicas de classificação de imagens baseadas em objetos. O resultado final é a geração de índices da condição da superfície do pavimento a partir das imagens que possam ser comparados com os indicadores vigentes da condição da superfície do pavimento já normatizados pelos órgãos competentes no país. Abstract in english Monitoring every Brazilian road use condition is an expensive and time consuming task. This research deals with new techniques which will yield a quick survey of road surface pavement condition by using hyperspectral images from airborne remote sensing. Recently, an increasing number of images with high spatial resolution has emerged on the world market with the advent of new remote sensing satellites and airborne sensors. Hyperspectral images from digital airborne sensor (more) have been used in this work. A new identification methodology for a pavement surface and also for classification of the main defects of the surface has been devised. The first step of the methodology is the identification of the asphalt surface in the image, by using hybrid classification based on pixel initially and then improved by objects. The second step of the methodology is the identification and classification of the main defects of pavement surface that are observable in high spatial resolution imagery. This step makes intensive use of new techniques for classification of images based on objects. The goal is the generation of pavement surface condition index from the images which can be compared to quality index of pavement surface already managed by the regulatory agency in the country.

Hydroplaning of vehicles is of concern to pavement engineers as it compromises travel safety in wet-weather. This paper presents a finite-element model to simulate hydroplaning of a locked wheel sliding on a flooded pavement surface. The main components of the model are described and the model is validated against experimentally-derived relationships. The effects of tire inflation pressure, wheel load and water-film thickness on hydroplaning speed are studied using the numerical model. It is found that hydroplaning speed increases with increasing tire pressure, increasing load and decreasing water-film thickness. It is observed that tire inflation pressure is a dominant factor affecting hydroplaning speed while wheel load and water-film thickness are secondary factors. For easy practical applications, a regression relationship of hydroplaning speed as a function of tire inflation pressure, wheel load and water-film thickness is developed using the results of the numerical simulations.   

Hot-mix asphalt (HMA) mixtures are widely used in the surface layer of flexible pavements. HMA mixtures are a kind of polymer matrix composite composed of polymeric asphalt mastic with the inclusion of particulate-filled media and air voids. Nowadays, more and more petroleum-based polymers (epoxy, resin) have been widely used in the HMA mixtures, in which the polymer matrix accounts for around 10-20% by volume. The properties of polymer matrix play a key role in the performance of flexible pavements.Dynamic modulus (E*) of HMA mixtures is one of the fundamental engineering properties measured by the simple performance tester (SPT) and has been incorporated as a basic input in the American Association of State Highway and Transportation Officials (AASHTO) Mechanistic-Empirical Design Guide ...

In many urban areas, pavements and roofs constitute over 60% of urban surfaces (roof 20-25%, pavements about 40%). The roof and the pavement albedo can be increased by about 0.25 and 0.10, respectively, resulting in a net albedo increase for urban areas of about 0.1. Many studies have demonstrated building cooling-energy savings in excess of 20% upon raising roof reflectivity from an existing 10-20% to about 60%. We estimate U.S. potential savings in excess of $1 billion (B) per year in net annual energy bills. Increasing albedo of urban surfaces can reduce the summertime urban temperature and improve the urban air quality. Increasing the urban albedo has the added benefit of reflecting more of the incoming global solar radiation and countering the effect of global warming. We estimate that increasing albedo of urban areas by 0.1 results in an increase of 3 x 10{sup -4} in Earth albedo. Using a simple global model, the change in air temperature in lowest 1.8 km of the atmosphere is estimated at 0.01K. Modelers predict a warming of about 3K in the next 60 years (0.05K/year). Change of 0.1 in urban albedo will result in 0.01K global cooling, a delay of {approx}0.2 years in global warming. This 0.2 years delay in global warming is equivalent to 10 Gt reduction in CO2 emissions.

Our lysimeter study addresses high-resolution analysis of the water balance of permeable pavements used for sidewalks and streets. Berlin's typical pavers, "Bernburg cobble stone" and "concrete paver" are analysed for actual evaporation, runoff and groundwater recharge. To achieve the reasonable boundary condition realistic seam material were bed in surface construction. The lysimeter bodies, filled with construction sand, stand in 1.5 m deep stainless cave on a scale with a 100g/sec resolution. The seepage water is captured by four suction plates with a suction of 63 hPa. To measure the run-off separately, special gutters are set up directly along the surface edge. This gutter leads the run-off water immediately to a separate discharge pipe and the run-off will be measured with a resolution of 0.0005 mm/sec; no water gets lost within this procedure. A dynamic runoff coefficient could be gained for a span of typical rainfall intensities. We will present runoff coefficients (RC) from both pavements as functions of the rainfall intensity, based on about 40 individual precipitation events. We could show that the rainfall intensity is the best predictor for the runoff behaviour. Concrete pavers can cause runoff with higher RC at lower intensity. However, for intensities > 0.1 mm/min their RCs tend to increase slower than those of mosaic cobble stone pavements. RCs might not be dependent on pavements during strong precipitation events. The measured RC are typical for the rainfall characteristic of Berlin, Germany and should not be used for other climate regions. First, the controlling variable must be identified and incorporated into process based models. Such models are essential for the prediction of urban evaporation so as to develop new urban water and climate management strategies.

Kangerlussuaq Airport is located at 67°N and 51°W in the zone of continuous permafrost in western Greenland. Its proximity to the Greenlandic ice sheet results in a dry sub-arctic climate with a mean annual temperature of ?5.7 °C. The airport is built on a river terrace mostly consisting of fluvial deposits overlying fine-grained marine melt-water sediments and bedrock. A ground-penetrating radar (GPR) survey was performed to study the frozen surface beneath the airfield. The measurements were carried out in late July 2005 on the southern parking area in Kangerlussuaq Airport. Five years earlier, in autumn 2000, three test areas were painted white in order to reduce further development of depressions in the asphalt pavement. GPR profiles crossing the white areas show a distinct difference in depth to the permafrost surface under the painted areas compared to the natural black asphalt surface. GPR data also show a correlation between structures in the river terrace and depressions in the paved surface. The combination of large dark areas of asphalt pavement and perhaps a change in snow removal routines on the southern parking area have caused an increase in solar heating, a lowering of the permafrost surface and the formation of several depressions in the pavement of the southern parking area. The depressions can be clearly seen after rainfall. To calibrate the GPR survey, sediment samples from a borehole were analyzed with respect to water content, grain size and content of organic material. To find the exact depth of the permafrost a trench was dug down to the frozen surface. © 2007 Elsevier B.V. All rights reserved.

Micro PAVER is a microcomputer version of the PAVER Pavement Maintenance Management System. PAVER is a field-tested, validated pavement maintenance management for airports, cities, counties, and military installations which is designed to optimize the fun...

The PAVER and Micro PAVER Pavement Maintenance Management Systems are designed to optimize the use of funds allocated for pavement maintenance and rehabilitation (MR). PAVER, a field-tested, validated mainframe computer system, and Micro PAVER a microcomp...

Flexible and rigid pavement test sections were constructed and trafficked to obtain data to validate present criteria or develop new criteria for the evaluation and design of airfield pavements subjected to multiple-wheel heavy gear loads. Traffic was app...

This paper introduces the summary of the Fifth International Conference on Concrete Pavement Design and Rehabilitation. The discussions at the conference were focused on designing methods for concrete pavement of roads and airport runways. The sessions were characterized in that continuous reinforced concrete pavement, rolling compaction concrete pavement, and noise were dealt independently, and the workshops discussed noise, bearing capacity, and construction. The noise was discussed in relation with noise suppressing techniques; the bearing capacity was discussed on design methods and measures against insufficiency in bearing capacity of pavement or non-uniform bearing capacities; and the construction was discussed from a viewpoint that pavement problems are attributable to lack of the uniformity in the construction. Lectures were given in the respective sessions on the following items: performance, rehabilitation, continuous reinforced concrete pavement, design, masonry joints, noise and materials, airport runway pavement, fibers and materials, overlay, and rolling compression concrete. 2 figs., 4 tabs.

;Contents: Hot in place recycling processes and equipment; HIPR as a tool for asphalt pavement rehabilitation; Mixture design for HIPR processes; Relative performance of HIPR pavements; Guidelines for effective use of HIPR; and Conclusions and recommendations.

Solar reflectance can vary with the spectral and angular distributions of incident sunlight, which in turn depend on surface orientation, solar position and atmospheric conditions. A widely used solar reflectance metric based on the ASTM Standard E891 beam-normal solar spectral irradiance underestimates the solar heat gain of a spectrally selective 'cool colored' surface because this irradiance contains a greater fraction of near-infrared light than typically found in ordinary (unconcentrated) global sunlight. At mainland U.S. latitudes, this metric RE891BN can underestimate the annual peak solar heat gain of a typical roof or pavement (slope {le} 5:12 [23{sup o}]) by as much as 89 W m{sup -2}, and underestimate its peak surface temperature by up to 5 K. Using R{sub E891BN} to characterize roofs in a building energy simulation can exaggerate the economic value N of annual cool-roof net energy savings by as much as 23%. We define clear-sky air mass one global horizontal ('AM1GH') solar reflectance R{sub g,0}, a simple and easily measured property that more accurately predicts solar heat gain. R{sub g,0} predicts the annual peak solar heat gain of a roof or pavement to within 2 W m{sup -2}, and overestimates N by no more than 3%. R{sub g,0} is well suited to rating the solar reflectances of roofs, pavements and walls. We show in Part II that R{sub g,0} can be easily and accurately measured with a pyranometer, a solar spectrophotometer or version 6 of the Solar Spectrum Reflectometer.

The main goal of the study was to discover knowledge from data about asphalt road pavement problems to achieve a better understanding of the behavior of them and via this understanding improve pavement quality and enhance its lifespan. Four pavement problems were chosen to be investigated; raveling ...

Abstract Uplifted during the 1964 Alaskan earthquake, extensive intertidal flats around Middleton Island expose 1300 m of late Cenozoic (Early Pleistocene) Yakataga Formation glaciomarine sediments. These outcrops provide a unique window into outer shelf and upper slope strata that are otherwise buried within the south-east Alaska continental shelf prism. The rocks consist of five principal facies in descending order of thickness: (i) extensive pebbly mudstone diamictite containing sparse marine fossils; (ii) proglacial submarine channel conglomerates; (iii) burrowed mudstones with discrete dropstone layers; (iv) boulder pavements whose upper surfaces are truncated, faceted and striated by ice; and (v) carbonates rich in molluscs, bryozoans and brachiopods. The carbonates are decimetre sca...

Disclosed is a rapid road repair vehicle capable of moving over a surface to be repaired at near normal posted traffic speeds to scan for and find an the high rate of speed, imperfections in the pavement surface, prepare the surface imperfection for repair by air pressure and vacuum cleaning, applying a correct amount of the correct patching material to effect the repair, smooth the resulting repaired surface, and catalog the location and quality of the repairs for maintenance records of the road surface. The rapid road repair vehicle can repair surface imperfections at lower cost, improved quality, at a higher rate of speed than was was heretofor possible, with significantly reduced exposure to safety and health hazards associated with this kind of road repair activities in the past.

breakage and surface distress in addition to rolling-element fatigue. ... 1 percent aluminum to give it better hot hardness capability and better nitriding capa- ... melted (CVM) Super Nitralloy (5Ni-2Al) and CVM AIS1 M-50 steel, at a ..... Preliminary heat treatment after rough machining ... -1 wide gear, thereby allowing for edge ...

Objective The accelerated deterioration of flexible pavement and its relation to design strength requirements is a major problem facing highway engineers. The goal of this research is to investigate a possible relationship between the accelerated pavement deterioration rates and pavement design strength using a two-stage design analysis approach. Approach Overview The approach in this study applies a two-stage solution to the three popular design methods of flexible pavement (i.e. California Department of Transportation (Caltrans) method, the American Association of State Highway and Transportation Officials (AASHTO) method, and the Asphalt Institute (AI) method) to yield pavement designs using stage load applications values specified for each investigated design load applications level. T...

Pavement temperature is one of the most important factors affecting the design and performance of roads. Actual pavement temperature is required to be considered in design standards for pavements roads which have spherical shapes. The heat distribution is highly influential in pavement structural design and have a large effect on indirect tensile stiffness modulus. This importance calls for special attention and interest in research to develop procedures for design and analysis that account for temperature considerations. However, temperatures at different depths in the pavement are difficult to measure. Therefore, a mathematical model for pavement temperature estimation from climatic data such as air temperature and solar radiation is presented. Maximum and minimum pavement temperatures a...

Several runway surface treatments developed in recent years are described in terms of how aircraft tire landing and takeoff friction requirements are met, particularly during adverse weather conditions. Changing the surface texture with grooving, grinding and shot peening, use of chemicals to remove or prevent accumulation of natural or man-made contaminants, and the use of new techniques and materials are discussed as means of improving surface friction performance. Test data are presented to illustrate the effects of runway conditions on aircraft ground performance. The severity of the problem of operating on runway surfaces which cannot provide sufficient aircraft tire friction capability is also illustrated from documented aircraft accident/incident reports. The paper concludes with recommendations for future pavement research activities.

A road-side seismic monitoring system has been developed that includes not only instrumentation and fielding methods, but also data analysis methods and codes. The system can be used as either a passive or active monitoring system. In the passive mode, seismic signals generated by passing vehicles are recorded. Analysis of these signals provides information on the location, speed, length, and weight of the vehicle. In the active mode, designed for monitoring pavement degradation, a vibrating magnetostrictive source is coupled to the shoulder of the road and signals generated are recorded on the opposite side of the road. Analysis of the variation in surface wave velocity at various frequencies (dispersion) is used in an attempt to develop models of the near-surface pavement velocity structure. The monitoring system was tested at two sites in New Mexico, an older two-lane road and a newly-paved section of interstate highway. At the older site, the system was able to determine information about vehicle velocity, wheel-base length and weight. The sites showed significant differences in response and the results indicate the need for further development of the method to extract the most information possible for each site investigated.

The lifespan of surfacing course materials like mastic asphalt on orthotropic steel deck bridges is quite short when compared with that of ordinary road pavements. Several problems including cracking and rutting of the surfacing materials have been reported in many countries. This is the second part of the two papers on characterisation of the behaviour of typical surface course materials for orthotropic steel deck bridges. In this paper, details of the constitutive model and its numerical implementation are presented. An important component of the model is an unconditionally stable, implicit Euler backward algorithm for the integration of the constitutive equations. Comparisons of model predictions and laboratory measurements at different temperatures, deformation rates and confining stre...

Moisture damage is a major factor in the deterioration of asphalt pavements. In order to combat this problem, it is essential to understand the effects of moisture on the adhesive and cohesive bonds in asphalt concrete mixtures. These effects can be quantified through the use of surface free energy, which is a thermodynamic material property that has been successfully used to select asphalt binders and aggregates that have the necessary compatibility to firm strong bonds and resist moisture damage.This study aimed at understanding the effects of material characteristics and additives on surface energy and the resulting bond between asphalt binders and aggregates. As such, the study involved measuring the surface free energy of 37 neat and polymer modified asphalt binders and 11 aggregates ...

This study focuses on the analysis of the behavior of unbound aggregates to offset wheel loads. Test data from full-scale aircraft gear loading conducted at the National Airport Pavement Test Facility (NAPTF) by the Federal Aviation Administration (FAA) are used to investigate the effects of wander (offset loads) on the deformation behavior of unbound aggregate layers in asphalt pavement test sections. The initial impetus for this study was the discovery that during a complete wander pattern some of the residual deformation caused by a single pass was recovered due to subsequent load applications offset by wander. The NAPTF applied a sequential wander pattern that covered 9 lanes of traffic spaced at 10.25 in. (260 mm) covering approximately 82% of all traffic from a standard normal distribution curve of real world taxiway traffic. Research into other full-scale airfield and highway tests indicates that this phenomenon is not unique to the NAPTF tests; this response to loading with wander has been recorded in full-scale tests since the early 1940's. This research has found that application of the wander pattern to the low and medium strength subgrade asphalt pavement test sections causes an "anti-shakedown" effect in the unbound aggregate layers. Essentially, study of multi-depth deflectometer data indicate that the unbound aggregate particles move because of the constantly changing load application lane. This movement negates the stabilization or shakedown expected in unbound aggregate layers under repeated loads and the strong stable particle matrix predicted to develop by shakedown theory never materializes. The second discovery in this work is that non-destructive falling or heavy weight deflectometer tests can be used to determine the relative damage in pavement foundations, i.e., unbound aggregate and subgrade layers. Two slope based deflection basin parameters, the Base Damage Index (BDI) and the Base Curvature Index (BCI) can be directly compared to determine the relative damage in the respective unbound aggregate and subgrade layers. Pinpointing the layer that is the likely cause of the system failure can help the pavement engineer correct the deficiency in the pavement system instead of only treating the symptoms. Discrete element modeling was also used to investigate the movement of unbound aggregate particles due to offset loads. The modeling indicates that the particles move from under the load application area to the sides, which in turn moves the particles initially to the side of the load application area upward because the particles moved from under the load area displace them. Wander or offset loads move the particles back under the initial load area causing particles in that area to move upward. The back and forth, upward and downward particle movement was readily apparent in the offset load application tests. Comparison of single load tests and multiple offset load tests indicates that particle movement is much greater when sequentially offset loads are applied. Comparison of channelized traffic and traffic with wander indicates that traffic with wander might be more detrimental to the unbound aggregate layers due to the increased movement and rearrangement of particles in the unbound aggregate layers. Measured transverse profiles and multi-depth deflectometer data were used to create individual pass residual deformation transverse profiles. The created transverse profiles were then combined with stress history effects to predict the residual transverse profiles for all test sections. This new permanent deformation model emphasizes the use of the previous load location and stress history of the pavement element to develop the residual deformation in that element. Calculation of the residual deformation in each element across the pavement surface results in the development of the complete permanent deformation transverse profile. This technique can be applied to estimate the transverse rutting profile of the pavement after trafficking based on any combination of applied wander and traffic direction. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.

By vacuum pyrolysis, the rubber portion of used tires is transformed into oil and gas and the carbon black filler is recovered as pyrolytic carbon black (CB{sub P}). Several commercial applications for the different products have been investigated and are reported in this article. CB{sub P} surface chemistry and activity are similar to those of commercial carbon blacks. Therefore, CB{sub P} has the potential to replace commercial carbon black grades in certain rubber applications. CB{sub P} was successfully tested as a filler in road pavement. The total pyrolytic oil can be used as a liquid fuel. The oil can also be distilled into different fractions: a light, a middle distillate and a heavy fraction. The light fraction was positively tested as a gasoline additive. Furthermore, this fraction contains valuable chemicals such as d,l-limonene. The middle fraction was successfully tested as a plasticizer in rubbers. The heavy fraction represents a good-quality feedstock for the production of coke and can also be used in road pavements. The pyrolytic gas can be used as a make-up heat source for the pyrolysis process

Discussions have been given on applicability of fine powders of shells removed from cleaning thermal power plant inlet channels as an asphalt pavement filler. Shells have a chemical composition mainly composed of calcium carbonate. An indoor test has verified that residual stability of an asphalt pavement meets the standard when shells were used as a filler for asphalt concrete. The filler's fluidity resistance was found equivalent to or better than the conventionally used fillers. A site verification test was performed using the road in a thermal power plant to compare the filler with three kinds of the conventional fillers. The result may be summarized as follows: all of the fillers achieved targets in such properties as a void rate and a saturation degree in the asphalt concrete; no filler lumps were recognized in any of the fillers, which were capable of being mixed uniformly; paving was possible by using the construction method given in the specifications; paved surface properties were found good in flatness, slip resistance, and bending; no difference was discovered in durability among the fillers; and the four kinds of the recovered asphalt presented no large difference in their properties. 8 refs., 14 figs., 10 tabs.

Three coastal sites oiled from the 1974 `Metula` oil spill in the Strait of Magellan were revisited in May 1998 to document oiling conditions 23.5 years after the spill. The sites revisited are in the Punta Espora area. Two are salt marshes and the third, an inter-tidal asphalt pavement. It was found that the marshes were still oil covered and bare of vegetation in most sections, although the tilling conducted in 1993 resulted in substantial increases in the number of plants that were able to recolonize. Application of fertilizer without tilling of the surface of the oil had no effect. By 1998 the oil, although still present, was weathered to a rubbery consistency. The large, 550 m. long asphalt pavement that had formed on the mixed-sediment beach remained, and showed relatively little change. Chemical analysis of the asphalt indicated extremely high degradation, including even some of the highly biodegradation-resistant biomarker compounds. The experimental treatment plots that were tilled in 1993 showed the highest level of weathered oil, and the highest degree of plant recolonization, suggesting that recolonization of the marshes could have been accelerated had tilling been conducted on these sites soon after the spill. 15 refs., 5 tabs., 6 figs.

...cracks, corrosion, and chrome plate distress; repetitive magnetic...M-30, West Building Ground Floor, Room W12-140, 1200 New...cracks, corrosion, and chrome plate distress; repetitive magnetic...cracks, corrosion, and chrome plate distress; do a magnetic...

Various simulations were carried out under various laying conditions to obtain the limitation of locating distance for ground penetrating radar. Recently, ground penetrating radar has been remarked as location technology of obstacles such as the existing buried objects. To enhance the theoretical model (radar equation) of a maximum locating distance, the following factors were examined experimentally using pulse ground penetrating radar: ground surface conditions such as asphalt pavement, diameter of buried pipes, material of buried pipes, effect of soil, antenna gain. The experiment results well agreed with actual field experiment ones. By adopting the antenna gain and effect of the ground surface, the more practical simulation using underground models became possible. The maximum locating distance was more improved by large antenna than small one in actual field. It is assumed that large antenna components contributed to improvement of gain and reduction of attenuation during passing through soil. 5 refs., 12 figs.

Multichannel analysis of surface waves (MASW) technique was employed for site characterization studies at the identified lineament locations along coastal regions of Andhra Pradesh covering ~600km to measure the shear wave velocity. The shear (S)-wave velocity of near surface materials (such as soil, rocks and pavement) and its effect on seismic wave propagation are of fundamental interest in many groundwater, engineering and environmental studies. Geologically, the study area comprises of Precambrian basement over which younger rocks commencing with Jurassic, Cretaceous, Tertiary and Quaternary have given rise to varying sequences in different parts. The study has been conducted along the lineaments and these were selected based on the analysis of IRS-1D LISS-IV satellite images and the f...

Formation of desert pavement and accretionary soils are intimately linked in arid environments such as the Mojave Desert. Well-sorted fallout scoria lapilli at Lathrop Wells (75-80 ky) and Red Cone ({approx}1 Ma) volcanoes (southern Nevada) formed an excellent starting material for pavement, allowing infiltration of eolian silt and fine sand that first clogs the pore space of underlying tephra and then aggrades and develops vesicular A (Av) horizons. Variations in original pyroclast sizes provide insight into minimum and maximum clast sizes that promote pavement and soil formation: pavement becomes ineffective when clasts can saltate under the strongest winds, while clasts larger than coarse lapilli are unable to form an interlocking pavement that promotes silt accumulation (necessary for Av development). Contrary to predictions that all pavements above altitudes of {approx}400 m would have been ''reset'' in their development after late Pleistocene vegetation advances (about 15 ka), the soils and pavements show clear differences in maturity between the two volcanoes. This indicates that either the pavement soils develop slowly over many 10,000's of years and then are very stable, or that, if they are disrupted by vegetation advances, subsequent pavements are reestablished with successively more mature characteristics.

ObjectivesTo provide an overview of patient and caregiver emotional distress; examine the sources of their distress, review evidence-based interventions that can reduce distress, and provide guidelines for assessment and intervention. Data SourcesPeer-reviewed publications. ConclusionThere is a significant, reciprocal relationship between patient and caregiver emotional distress. Sources of distress vary by phase of illness. Evidence-based interventions can reduce distress and anxiety, but often are not implemented in practice. Implications for Nursing PracticeNurses need to assess patients and family caregivers for distress and intervene to reduce distress by fostering patient-caregiver teamwork, communication, and self-care; providing information; and referring to resources as needed.

Vesicular structure is a widespread feature of soils in arid environments. Typically associated with stone pavements, it has a major control function for dust and water fluxes and, hence, for site ecology. Previous models of vesicular structure formation and stability are inconsistent and mostly focused on the investigation of isolated control parameters. To test existing models, to infer plausible mechanisms of vesicular structure formation and to unveil controlling environmental and sedimentological parameters, we present quantitative data of vesicle properties of artificial and natural vesicles. Vesicles are not unstable but their changes in size are non-linear with time. They form due to surface sealing by puddling and by a wetting front, which advances downward, thereby elevating gas ...

Acoustic impedance determines the boundary condition of each sound field, but collections of actual values to evaluate sound fields are insufficient. Therefore, measurements of acoustic impedance using a particle velocity sensor were taken on different fields. Such measurement results were used for sound propagation calculations. Frequency characteristics of sound propagation on grass, snow-covered, and porous drainage pavement surfaces showed fair correspondence with field measurement results. Subsequently, fine calculations in the frequency domain were converted to impulse responses for each sound field model. Convolution operations based on the impulse response and on voice, music, and other noise sources readily produced an ideal sound field for the audible sound file. Furthermore, simulations of noise from a car running through a paved drainage area, with noise reduction effects, were attempted as advanced applications.   

Natural stones are exposed to physical weathering due to freezeâ??????thaw (Fâ??????T) and thermal shock (TS) when they are used as pavement, cladding and masonry material. In this study, the deterioration of andesite was investigated by determining the physical and mechanical properties of andesite samples after each 10 cycles of Fâ??????T and TS up to 50 cycles. It was found that the P-wave velocity, Schmidt hardness and compressive strength decrease to different extents with Fâ??????T and TS while porosity and water absorption increase with Fâ??????T cycles but decrease with TS cycles. The results showed that Fâ??????T has a more destructive effect on the studied material than TS, although abrasion loss measurements suggest that the effect on the surface of the material is greater...

Moisture damage is of great negative impacts on asphalt pavement. It exacerbates the service performance (e.g., rutting, cracking) for asphalt mixture under traffic load. This paper describes the influence of surface treated fly ash with silane coupling agent on asphalt mixture moisture damage. The filler combined with coupling agent and fly ash was named compound fly ash modifier (CFAM). Primarily the properties of CFAM were characterized by Scanning Electron Microscopy and Fourier Transform Infrared Spectroscopy. As filler, its effects on moisture sensitivity of asphalt mixture were evaluated by modified Lottman test, indirect tensile stiffness modulus test, static creep and indirect tensile fatigue test. It is shown that the asphalt mixture with CFAM has excellent moisture sensitivity i...

The quality of a road relies on the good use of the on road surface and its maintenance along the years. The technology used and the corrections contributes to the prevention of early road destructions. Pavement with polmyer and others additives exhibits greater resistance to rutting, thermal cracking, and decreased fatigue damage, stripping and temperature susceptibility. Samples of CAP 40, SBS 440/02, L 1861/04, L 784/05 and L 2000/04 were analyzed by thermogravimetry (TG), derivative thermogravimetry (DTG), differential thermal analysis (DTA) and FTIR. Thermal characterizations showed that the main decomposition stage refers to asphaltenes and samples with additives exhibited a slight increase in thermal stability. The kinetic study, by Kissinger, showed that the sample with the highest...

The purpose of this article is to present some important advances in the imaging techniques currently used in the characterization of bitumen and bituminous emulsions. Bitumen exhibits some properties, such as a black colour and a reflecting surface at rest, which permit the use of optical techniques to study the macroscopic behaviour of asphalt mixes in the cold mix technology based on emulsion use. Imaging techniques allow monitoring in situ the bitumen thermal sensitivity as well as the complex phenomenon of emulsion breaking. Evaporation-driven breaking was evaluated from the shape of evaporating emulsion drops deposited onto non-porous and hydrophobic substrates. To describe the breaking kinetics, top-view images of a drying emulsion drop placed on an aggregate sheet were acquired and processed properly. We can conclude that computer-aided image analysis in road pavement engineering can elucidate the mechanism of breaking and curing of bituminous emulsion. PMID:17825782

The performance of porous asphalt (PA) mixes as opposed to open-graded friction course (OGFC) mixes for use in pavement rehabilitation was evaluated. Rehabilitation strategies included seal coats, chip seals, and thin overlays. In North America the thin overlays are commonly dense-graded hot mix asphalt concrete or OGFC mixes, while in Europe, PA mixes are used. Both provide good surface drainage, but test results showed that PA mixes had higher resistance to permanent deformation as compared to OGFC mixes. Volumetric properties for PA mixes may be difficult to achieve under local aggregate sources and type limitations. Hard stones and cubical particle shapes should be used with a minimum of flat and elongated particles. Limestone aggregate was not hard enough and did not result in appropriate volumetric properties. It was recommended that the use of trap rock aggregates, which provide more cubical shaped particles, be investigated. 6 refs., 2 tabs., 5 figs.

By international literature and bench-scale experiments all the promising, local measures to improve air quality along highways were studied in the IPL-programme. Measures concern the impact of fencing, the road surface, catalytic (paint) layers, coverings of the road, including air conditioning, vegetation and dynamic traffic control. From this article it appears that about half of the PM10-emission of car traffic is caused by wear and comes from the pavement. [Dutch] Op basis van internationaal literatuuronderzoek, laboraloriumonderzoek en praktijkonderzoek onderzocht het IPL alle kansrijke, lokale maatregelen voor de verbetering van luchtkwaliteit langs snelwegen. Het ging om het effect van schermen, het wegdek, katalytische (verf)lagen, overkappingen van de weg inclusief luchtbehandeling, vegetatie en dynamisch verkeersmanagement. Uit dit artikel blijkt dat op termijn de helft van de PM10-emissies van het autoverkeer te maken heeft met slijtage en wegdekken.

BHP Engineering have been able to develop and refine the design of haul roads using long term site experience. Many standard design practices have been reassessed and modified to give more appropriate and cost effective road pavements and geometry. This paper describes the cost advantage obtained, haul road planning, the design of haul road speed and grade, superelevation, pavements, and drainage.

The falling weight deflectometer (FWD) is used worldwide as an established, valuable, nondestructive road testing device for pavement structural analyses. The FWD is used mostly for rehabilitation project level design investigations and for pavement management system (PMS) monitoring on a network b...

Pavement recycling has been an important rehabilitation technique to deal with reclaimed materials from old pavements which are usually sent to landfills. The application of this technique contributes to: i) the accomplishment of the requirements defined by the European legislation for the amount of...

A pavement condition survey was performed on the South Base airfield at Edwards Air Force Base, CA, in August 1989 for the purpose of determining the pavement condition index of the airfield features and for performing the initial implementation of the PA...

The use of a pervious pavement can be effective as a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete paver systems as a type of porous pavement. Although the pavers are impermeable, the spaces between the pave...

In 1981 the New Brunswick Department of Transportation (NB-DOT) called for tenders on a 6.7 km road project which was to include the recycling of existing pavement and the contract was awarded to Eastern Paving Ltd. The existing pavement was ripped, loaded onto trucks, delivered to the processing site, crushed and stockpiled with protection from rain. Samples of virgin aggregate, local sand, and crushed, recycled asphalt paving were analysed by the NB-DOT central laboratory. The lab also tested possible mixes and ultimately provided an optimum design which contained 50% recycled asphalt pavement. Project accounting indicates the 50/50 mix was 19% less expensive to produce than a 100% virgin mixture. In addition an amount of surplus reclaimed pavement almost equal to that used in the project remains stockpiled. With a doubling of the ownership cost to allow for maintenance and upgrading over a ten year period, and without consideration of the value of the stockpiled pavement remaining, the hardware investment shows a payback period of 2.5 years. Environmental pollution, in the form of blue smoke emissions, was slightly more than expected but should be greatly reduced or eliminated by minor plant modifications and increased production rates. Elements of concern for future pavement recycling projects are sub-base contamination when removing oil pavement; estimating the gradation of aggregates in recycled pavement and consequent virgin aggregate requirements; the moisture content of recycled asphalt paving; stockpile consolidation; crushing procedures; and moisture content allowable in the product mix. 19 figs., 2 tabs.

The report includes the results of an analytical study of the effects of automobile tire loads on thin asphalt pavements over flexible bases. Two different ways of calculating the tire contact pressure were used and the strains induced in the pavement str...

In Sweden, use of industrial residues is still hindered by concern for their long-term properties. A three-year research project was therefore initiated aiming to (1) identify the crucial processes of ageing related to the usefulness of residues in roads; (2) investigate the consequences of these processes for technical and environmental properties of the residues, and (3) propose a method for accelerated ageing to predict the long-term properties. This paper gives an overview of the project methodology, a summary of the test results and references to papers where further details are given. The project, running through 2006-2008, compared naturally aged samples of two residues used as sub-bases in existing asphalt paved roads with samples of fresh residues from producers' piles. Steel slag of electric arc furnace (EAF) type and municipal solid waste incinerator (MSWI) bottom ash were chosen. The samples were thoroughly characterised in order to identify which ageing processes had been crucial. The results showed that: - Bottom ash from the pavement edge was more aged than bottom ash from the road centre. However, no difference in pH was found, instead the differences were caused by differences in water exposure. - Steel slag from the pavement edge showed traces of carbonation and leaching processes, whereas slag from the road centre was identical to fresh slag. - Water exposure to the subbase materials after ten years in an asphalt paved road was calculated to less than 0.1–0.5 litres per kg. - Ageing reactions in steel slag and MSWI bottom ash, ready for use, were too small to be verified by laboratory measurement of deformation properties under loaded conditions. An accelerated ageing test for steel slag was set up to achieve the carbonation (decrease in pH) and leaching that was observed in the pavement edge material. An accelerated ageing test for bottom ash was set up to achieve the pozzolan reactions that were observed in SEM analyses of in situ specimens. It is recommended to use uncrushed particles when properties of aged material are studied, in order to preserve the original particle surfaces. PMID:20932737

Backcalculation analysis can be used to find the material properties of pavement. However, most backcalculation programs are based on the linear-elasticity assumption, and the material properties obtained are rarely used for pavement analysis. Laboratory results have shown that pavement materials possess a nonlinear stress-strain relationship. The purpose of this study is to develop a nonlinear backcalculation program which will be used to analyze the properties of the test pavement sections in the Long-Term Pavement Performance (LTPP) database in the United States. The Falling Weight Deflectometer (FWD) test results from these test sections will be compared with the predicted results from linear and nonlinear backcalculation analysis. The backcalculated material properties will also be used to predict the deflections of the FWD test data for different drop weight. Finally, the backcalculation results will be used for the structural analysis.   

The financial distress forecasting has long been of great interest both to scholars and practitioners. The financial distress forecasting is basically a dichotomous decision, either being financial distress or not. Most statistical and artificial intelligence methods estimate the probability of financial distress, and if this probability is greater than the cutoff value, then the prediction is to be financial distress. To improve the accuracy of the financial distress prediction, this paper first analyzed the yearly financial data of 1888 manufacturing corporations collected by the Korea Credit Guarantee Fund (KODIT). Then we developed a financial distress prediction model based on radial basis function support vector machines (RSVM). We compare the classification accuracy performance betw...

Hypersensitivity reactions to liposomal drugs, often observed with Doxil and AmBisome, can arise from activation of the complement (C) system by phospholipid bilayers. To understand the mechanism of this adverse immune reaction called C activation-related pseudoallergy (CARPA), we analyzed the relationship among liposome features, C activation in human serum in vitro, and liposome-induced cardiovascular distress in pigs, a model for human CARPA. Among the structural variables (surface charge, presence of saturated, unsaturated, and PEGylated phospholipids, and cisplatin vs. doxorubicin inside liposomes), high negative surface charge and the presence of doxorubicin were significant contributors to reactogenicity both in vitro and in vivo. Morphological analysis suggested that the effect of ...

A non-hydrostatic, mesoscale model, LOCALS, is used to investigate the effect of land surface changes on precipitation in an urban area. The horizontal mesh used in the model is approximately 5 km and the domain includes Tokyo and central Japan. Land surfaces identified as pavement or urban are transformed into forested land and model simulations are performed for both the current urban land surface and the hypothetical forested land surface. Detailed analysis is performed for two sample cases. On 5 August 2003, increased heating by the urban surfaces increases the height of the urban boundary layer resulting in much more rainfall. On 25 July 2001, air that is advected over Tokyo but forms a precipitating cloud away from the urban core carries less moisture and therefore produces less rainfall. These case studies suggest that changes to land surface types in urban areas may increase or decrease rainfall in the urban area and further research is necessary before it is possible to generalize these results.   

Data on materials and surface types that comprise a city, i.e. urban fabric, are needed in order to estimate the effects of light-colored surfaces (roofs and pavements) and urban vegetation (trees, grass, shrubs) on the meteorology and air quality of a city. We discuss the results of a semi-automatic statistical approach used to develop data on surface-type distribution and urban-fabric makeup using aerial color orthophotography, for four metropolitan areas of Chicago, IL, Houston, TX, Sacramento, CA, and Salt Lake City, UT. The digital high resolution (0.3 to 0.5-m) aerial photographs for each of these metropolitan areas covers representative urban areas ranging from 30km2 to 52km2.Major land-use types examined included: commercial, residential, industrial, and transportation. On average, for the metropolitan areas studied, vegetation covers about 29–41% of the area, roofs 19–25%, and paved surfaces 29–39%. For the most part, trees shade streets, parking lots, grass, and sidewalks. At ground level, i.e., view from below the tree canopies, vegetation covers about 20–37% of the area, roofs 20–25%, and paved surfaces 29–36%.   

The cratered plains of Gusev traversed by Spirit are generally low-relief rocky plains dominated by impact and eolian processes. Ubiquitous shallow, soil-filled, circular depressions, called hollows, are modified impact craters. Rocks are dark, fine-grained basalts, and the upper 10 m of the cratered plains appears to be an impact-generated regolith developed over intact basalt flows. Systematic field observations across the cratered plains identified vesicular clasts and rare scoria similar to original lava flow tops, consistent with an upper inflated surface of lava flows with adjacent collapse depressions. Crater and hollow morphometry are consistent with most being secondaries. The size frequency distribution of rocks >0.1 m diameter generally follows exponential functions similar to other landing sites for total rock abundances of 5-35%. Systematic clast counts show that areas with higher rock abundance and more large rocks have higher thermal inertia. Plains with lower thermal inertia have fewer rocks and substantially more pebbles that are well sorted and evenly spaced, similar to a desert pavement or lag. Eolian bed forms (ripples and wind tails) have coarse surface lags, and many are dust covered and thus likely inactive. Deflation of the surface _5-25 cm likely exposed two-toned rocks and elevated ventifacts and transported fines into craters creating the hollows. This observed redistribution yields extremely slow average erosion rates of _0.03 nm/yr and argues for very little long-term net change of the surface and a dry and desiccating environment similar to today's since the Hesperian (or _3 Ga).

The effects of various parameters on an experimental concrete pavement were evaluated. Variables included in the pavement were (1) joint spacing, (2) subbase stabilization, (3) coating of dowel bars, (4) configuration of the saw cut, and (5) the use of skewed joints. Both long term and short term horizontal movements caused by temperature and vertical movement of slab ends under known axle loads were measured. A record of cracking and spalling of the pavement is also included. A statistical analysis of both long and short term movements was conducted and recommendations for joint design are included.

This article presents an evaluation of the safety impacts of four engineering treatments implemented in the Autonomous Community of Madrid (Spain): highway upgrading; updating and improvement of traffic signing; repainting of pavement markings and pavement resurfacings. This evaluation was carried out using the Empirical Bayes method with a comparison group. The functioning of a methodology to test the significance of the safety impact is described. The results show that highway upgrading has a positive and significant safety impact, while the updating and improvement of traffic signing, the repainting of road markings and pavement resurfacings do not exhibit a significant impact on safety. PMID:16236232

Citicolin, a psychodrug, is usually used for the treatment of ischemic cerebropathies. Its introduction into pulmonological therapy is suggested because Citicolin has the following properties: 1. Prevention of "acute respiratory distress syndrome" in neonates. 2. Improvement of chronic respiratory insufficiency. 3. Prevention of postoperative hypoventilation syndrome. 4. Improvment of respiratoy mechanics in syndromes with hyperelasticity of the lungs. 5. Recovery of permeability of the alveolo-capillary barrier for gases. 6. Compensation of the loss of surface-active substances after endobronchial aspiration of intubated patients. PMID:819809

In many European cities air quality is a massive problem. Besides the particulate matter, nitrogen oxides (NOX) and volatile organic compounds (VOC) are mainly responsible for the heavy pollution. Motivation to “do something” to protect the environment and climate is increasing constantly. Pollutants such as nitrogen oxides can be oxidized by means of photolysis. With the help of photocatalytic active particles this effect can be accelerated extensively. Photocatalytic active particles dispersed in the concrete turn it into an air pollutant reducing surface. Pollutants getting in contact with the concrete surface are decomposed or oxidized and therewith rendered harmless. This brand new technique is introduced into building industry with a new label “TX Active®“. A premium brand cement for the production of photo catalytically active concrete products - TX Active® products - is now available in the form of TioCem®. This cement can effectively contribute to air purification by using in numerous concrete components such as pavement, roof tiles, facade plates, concrete road surfaces, mortars etc.

The report summarizes the results of an investigation to determine physical, chemical and selected engineering properties of six Southeast Asian soils encountered in pavement facility construction. Lime and cement manufactured in the United States were us...

Abstract: Deteriorating pavements require timely application of rehabilitation actions. This article presents reliability-based optimization models for scheduling rehabilitation actions for flexible pavements. The pavement reliability and the effect of rehabilitation actions are modeled using parametric fragility curves based on simulated pavement responses. Three models are presented: MIN-C, a model that minimizes the cost where the target reliability is set as a constraint; MAX-R, a model that maximizes the cumulative life-cycle reliability where the budget is set as a constraint; and minimize cost and maximize reliability (MINMAX), a multi-objective model that determines Pareto optimal solutions to reliability-cost trade-off. As the multi-objective optimization model is nonlinear and no...

State Departments of Transportation, including the Texas Department of Transportation (TxDOT), have been moving towards the development and implementation of pavement management systems that would enable monitoring of the performance of their roadways, as...

Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, grade...

Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, gra...

The study reported herein compared polymer concrete pavement markings (Permastripe) to Federal specification waterborne airfield marking paint for field durability and retroreflectivity. The markings were placed at Tyndall Air Force Base (AFB) (hot, wet c...

This research, using focus groups and surveys of individuals who had experienced hurricane evacuations in Texas, assessed various hurricane evacuation traffic signs and pavement markings for developing guidelines. This report contains the process and find...

This report presents the recommendations to improve the vehicle and equipment warning light policy for the Texas Department of Transportation, and improve the safety of the department's pavement data collection activities. Research efforts include a natio...

The development of the Mechanistic-Empirical Pavement Design Guide (MEPDG) provides an opportunity to simulate the performance of pavements. This paper considers the impact of fine aggregate on the predicted performances of pavements by simulating the performance differences between pavement mixes prepared with different sources of fine aggregate with different gradations using the MEPDG. A natural and four manufactured sands from parent material consisting of dolomite, limestone, traprock (TR) and a glacial gravel (GG), and five gradations were utilised in this study. This resulted in 19 different sand/stone combinations being tested for dynamic modulus to enable level 1 analysis in the MEPDG. The results indicate that the fine aggregate angularity (FAA) test adequately ranks aggregates f...

Due to the harsh conditions of airport environments, frequent repainting of existing waterborne pavement markings is required. This painting is expensive and affects life-cycle costs. A thermoplastic marking material has been identified as an alternative ...

Mar 19, 2004 ... Glyphosate, isopropylamine salt 38641-94-0. N/R. N/R ..... Recycling: Recycling is the most preferred method of waste minimization for those hazardous .... KDP- KSC-P-1728. Rev. B. No. No ... pavement. While under load test ...

...Pavement Marking Materials and Markers: Real-World Relationship Between Retroreflectivity...needed for drivers to estimate roadway alignment, particularly roadway curvature...Order 12630, Governmental Actions and Interference with Constitutionally Protected...

A literature review was made to support an ongoing study to develop a method for evaluating airport pavements based on the layered elastic theory and using constants as determined from vibratory test results. The review covered the definitions and relatio...

Objectives: Sedentary behaviour and physical activity may be an independent risk factor for psychological distress in adolescents, although there is no existing information in children. We examined the cross-sectional association between psychological distress, television and screen entertainment (T...

The practice of routine screening for distress in cancer populations has been gaining worldwide support over the past several years with the conceptualization of distress as the sixth vital sign. Across Canada, experience with screening for distress is growing, as cancer facilities implement screening programs. Early learning from these efforts has emphasized the need for a programmatic approach and the importance of oncology nurses in screening and providing the initial response to distress. To date, little has been written from the nursing perspective about the oncology nursing role in a program screening for distress and responding to the identified patient concerns. This article describes the current thinking about distress; explores how screening for and responding to distress is integral to oncology nursing practice; and shares the early learning and experiences of cancer nurses in implementing screening for distress initiatives. PMID:22443045

Traffic crashes represents a loss of 2.2 percent of the U.S. Gross Domestic Product a year. By reducing congestion and the number of dangerous construction zones it is possible to increase user safety with fewer accidents. This new system once implemented eliminates many major national road preservation projects, which include replacing or reconstructing the highway pavements over the long period. Other included costs like those of lost time and lost fuel incurred by passenger and freight transportation on the section being reconstructed amount to well over 100 billion dollars a year. All other things being equal, thicker concrete highway pavements will last longer, however, thicker pavement costs more. By utilizing the physics of the T-Beam or the ``floor-joist,'' concept where the upper deck of the highway is supported and reinforced by longitude beams or rails that protrude into the soil, there is a great improvement in the strength of the pavement system. The pavement structure configuration of rails supports and carries vehicle loads, which is transferred ``down-the-road.'' Much like a snowshoe or like a rail bridge this device spreads out the applied stresses over a much larger area and the high strength pavement resists flexing of the concrete. Stress reduction reduces concrete fatigue and this allows the highway to last three to four times as long without major road reconstruction. To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2007.OSS07.P1.2

Main conclusions: 1) The Asphalt Strain Gauges (ASG), the Soil Deformation Transducers (SDT) and the Soil Pressure Cells (SPC) performed well during the experiment, but the SPCs need frequent in situ calibration. A different installation procedure for the SPCs should be considered. Due to the variability of the soil more instruments (than two) are needed for each response value to be determined. 2) Strains measured using the emu coils did not have a satisfactory degree of accuracy. Laboratory tests showed the Kulite pressure cells to be dependent upon loading history and soil stiffness. For this reason the cells were not used in the RTM experiment. The volumetric moisture content recorded by the VITEL moisture probes did not appear to be reliable. 3) Linear elastic theory did not give a satisfactory agreement with measured stresses and strains. The measured vertical strains could be several times larger than the theoretical values. Elsym5 seems to produce incorrect deflections in some cases. 4) Satisfactory agreement between measured and theoretical stresses and strains could be obtained using the Finite Element Method and appropriate non-linear relationships for the moduli of the unbound materials. 5) The variation of stresses and strains with distance from the load was found to be in very good agreement with Boussinesgs equations, with the exception of the horizontal stress. The relationship between the depth used with Boussinesq's equations the the actual depth needs further study. 6) The subgrade showed thixotropyc behavior with strains increasing with the number of load repetitions and decreasing after a rest period. This behavior was only observed under the wheel load, not under the FWD. 7) Existing design criteria for subgrades appear to be reasonable when used with strains calculated using linear elastic theory and moduli determined from FWD tests, but ar much too conservative if used with measured strains. 8) Plastic strain in the subgrade, surface rutting and roughness could all be related to the measured resilient strain at the top of the subgrade, with damage being proportional to the load raised to a power between 6.23 and 6.67. These relationships can be used to calculate the pavement condition after a given number of loads or to determine the permissible number of loads for a given terminal condition of the pavement. For surface rutting and roughness the contribution from the individual layers could not be established.

BACKGROUND: Moral distress is associated with job dissatisfaction, turnover and early retirement. Because of these negative consequences moral distress should be reduced. Little research has been done on what job factors contribute to whether or not a situation causes moral distress. OBJECTIVE: To identify individual and job characteristics associated with moral distress in nursing staff. DESIGN: This is a cross sectional correlational study. Nursing staff members completed two survey questionnaires with a time-interval of 3 months. In the first survey questions were asked about job characteristics and job satisfaction. Three months afterwards the respondents answered questions on moral distress. PARTICIPANTS: 365 nursing staff members employed in nursing homes, homes for the elderly, home care and acute care hospitals completed both questionnaires. RESULTS: High moral distress levels were related to lower job satisfaction. Moral distress is higher when nurses perceive less time available to give care to patients. If satisfaction with the consultation possibilities within the team is low and when an instrumental leadership style exists, nursing staff members are also more likely to experience moral distress. Nursing staff members working 30-40h per week experience less moral distress than colleagues working fewer hours per week. Multivariate analyses showed no relations with other individual characteristics measured. CONCLUSION: Job characteristics that contribute to moral distress should be an issue for managers because it is related to job satisfaction. Interventions to reduce moral distress should target at organisational issues. The way a team is supported can raise or decrease moral distress levels. PMID:22989404

A previously healthy young man presented to A&E with severe dyspnoea. The cause of his distress was bilateral spontaneous pneumothoraces. Prompt insertion of chest drains relieved his distress. This rare clinical entity should be considered in an individual with severe respiratory distress. Diagnosi...

This report describes the general spill phenomenology for liquid spills occurring on relatively impermeable surfaces such as concrete or asphalt pavement and the development and application of a model to describe the time evolution of such spills. The discussion assumes evaporation and degradation are negligible and a homogeneous surface. In such an instance, the inherent interfacial properties determine the spatial extent of liquid spreading with the initial flow being controlled by the release rate of the spill and by the liquids resistance to flow as characterized by its viscosity. A variety of spill scenarios were simulated and successful implementation of the model was achieved. A linear relationship between spill area and spill volume was confirmed. The simulations showed spill rate had little effect on the final spill area. Slope had an insignificant effect on the final spill area, but did modify spill shape considerably. However, a fluid sink on the edge of the simulation domain, representing a storm drain, resulted in a substantial decrease in spill area. A bona fide effort to determine the accuracy of the model and its calculations remain, but comparison against observations from a simple experiment showed the model to correctly determine the spill area and general shape under the conditions considered. Further model verification in the form of comparison against small scale spill experiments are needed to confirm the models validity.

Objective: Psychological distress is a key risk factor for long-term complaints in fibromyalgia (FM). Prognostic factors for psychological distress might facilitate an early identification of patients at risk to help prevent long-term dysfunction, especially for the relatively well-functioning patients showing little distress who are usually not considered for treatment. This study hence examines potential prognostic factors in this subgroup. Methods: Psychological distress, physical functioning, illness cognitions (helplessness, acceptance), pain-avoidance factors (passive pain-coping, fear of pain, hypervigilance), and social factors (social support, social reinforcement) was assessed in 78 low-distress FM patients at baseline and after a mean of 9 months (SD=3.3). Results: Baseline phys...

Substantial resources are invested in psychological support for children orphaned or otherwise made vulnerable in the context of HIV/AIDS (OVC). However, there is still only limited scientific evidence for greater psychological distress amongst orphans and even less evidence for the effectiveness of current support strategies. Furthermore, programmes that address established mechanisms through which orphanhood can lead to greater psychological distress should be more effective. We use quantitative and qualitative data from Eastern Zimbabwe to measure the effects of orphanhood on psychological distress and to test mechanisms for greater distress amongst orphans suggested in a recently published theoretical framework. Orphans were found to suffer greater psychological distress than non-orpha...

Background Psychologic distress contributes to symptom severity in patients with several musculoskeletal disorders. While numerous shoulder outcome instruments are used it is unclear whether and to what degree psychologic distress contributes to the scores. Questions/purposes We asked (1) to what degree shoulder outcome instruments reflect patientsâ?? psychologic distress, and (2) whether patients who are strongly affected by psychologic distress can be identified. Methods We prospectively evaluated 119 patients with chronic shoulder pain caused by degenerative or inflammatory disorders using the Constant-Murley scale, Simple Shoulder Test (SST), and Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire. To evaluate psychologic distress, we measured depression using the Center f...

The burial age of an alluvially deposited cobble pavement at the Tapada do Montinho archaeological site (east-central Portugal) is investigated using optically stimulated luminescence (OSL) dating. Measurements on the cobbles (quartzite clasts) were carried out on intact slices and large aliquots (~8 mm) of quartz grains (63– 300 mm), both recovered from the outer 1.5-mm surface of the cobbles. The recycling ratio, recuperation and dose-recovery tests show that the single-aliquot regenerative-dose (SAR) protocol is applicable to both rock slices and quartz grains; both have similar luminescence characteristics. The variation in the natural OSL signal with depth below the cobble surface using intact slices from two different cobbles shows that both were bleached to a depth of at least ~2 mm before deposition. A model of the variation of dose with depth fitted to data from one of the cobbles gives a burial age of ~19 ka and also predicts the dose-depth variation at the time of deposition. Ages based on rock slices suggest that one cobble surface, and the inner parts of two other cobbles experienced a resetting event at ~45 ka, consistent with the age control. However, the surfaces of the other cobbles all record light-exposure events in the range 26 to 14 ka, suggesting that some of the cobbles were exposed to daylight perhaps more than once in this period. Given the shallow burial depth and unexpectedly young ages of the surrounding and overlying finer-grained sediment, it is suggested that phases of light exposure following surficial erosion are probably responsible for this underestimate. Nevertheless, it is remarkable that we can identify and quantify four events (two light exposures of different durations and two sequential burial periods) in the dose record contained within a single clast, and this suggests that the luminescence dating of rock surfaces may prove, in the future, to be at least as important as sand/silt sediment dating.

This study aimed to: (1) develop and evaluate the Moral Distress Scale for Psychiatric nurses (MDS-P); (2) use the MDS-P to examine the moral distress experienced by Japanese psychiatric nurses; and (3) explore the correlation between moral distress and burnout. A questionnaire on the intensity and frequency of moral distress items (the MDS-P: 15 items grouped into three factors), a burnout scale (Maslach Burnout Inventory - General Survey) and demographic questions were administered to 391 Japanese psychiatric nurses in 2007-2008. These nurses experienced relatively low levels of moral distress despite the fact that they were commonly confronted by morally distressing situations. All the circumstances in which the participants experienced moral distress were included in the 'low staffing' factor, which reflects the characteristics of Japanese psychiatric care. The frequency score of the low staffing factor was a significant predictor of burnout. PMID:21097971

This paper simultaneously investigates the responses of stock prices of the related banks and the client firms when one of them is in distress. Two effects are examined. The distressed bank effect, which claims that the stock price of client firms are coupled to that of their related distress banks, and the distressed firm effect, which claims that the related banks are negatively affected when their client firms are in distress. We collect the detailed information of individual transaction loan data to find the relationship between banks and their client firms. Asymmetric responses are reported in this paper. Our results reject the distressed bank effect but, by contrast, cannot reject the distressed firm effect. We propose the fund diversification hypothesis and the leverage hypothesis, ...

Both traffic noise and wet pavement-tire friction are mainly affected by the tire/pavement interaction. Existing laboratory test methods allow for evaluation of polishing resistance of the aggregates only. Currently, there is no generally accepted standardized laboratory test method to address noise related issues and the overall frictional properties of pavements (including macrotexture). In this research, which included both laboratory and field components, friction and noise properties of the flexible (asphalt) pavements were investigated. As a part of this study, a laboratory device to polish asphalt specimens was developed and the procedure to evaluate mixture frictional properties was proposed. Following this procedure, forty-six different Superpave mixtures (each utilizing a different aggregate blends), one stone matrix asphalt (SMA) mixture and one porous friction course (PFC) mixture were tested. Six of the above mixes (four Superpave mixtures, SMA mixture and PFC mixture) were selected for laboratory noise testing. This testing was performed using a one-of-a-kind tester called the Tire/Pavement Test Apparatus (TPTA). In addition, the field sections constructed using Superpave, SMA and PFC mixtures were also periodically tested for friction and noise. Field measurements included testing of total of 23 different asphalt and two concrete pavements. The field friction testing was performed using both portable CTM and DFT devices and the (ASTM E 274) locked wheel friction trailer. The laboratory friction testing was performed using CTM and DFT devices only. The results of both field and laboratory friction measurements were used to develop an International Friction Index (IFI)-based frictional requirement for laboratory friction measurements. The results collected in the course of the study indicate that the IFI-based flag values could be successfully used in place of SN-based flag values to characterize frictional characteristics of pavements.

This study seeks to analyze which are the variables associated with the difficulty of elderly people with disabilities gaining access to the health services. This is an observational study of an analytical cross-sectional nature, with a sample of 244 elderly people with disabilities. Data relating to socio-economic profile, the nature of the disability, and the conditions of access to health services were gathered. Version 11.0 of the Statistical Package for the Social Sciences software was used for descriptive, statistical and analytical assessment of the data. The protection variables for difficulties in being treated in the health services were: the lack of drains, culverts, trash, bags of refuse, or irregular floor surfaces; the absence of ramps on sidewalks and pavements; the availability of transport; ease in scheduling appointments; and the length of the waiting period to be attended. The number of factors listed shows that the architectonic barriers and the current situation of healthcare need to be adequate in order to ensure full access and use by the elderly with disabilities to the health services. PMID:23175306

Tire and road wear particles (TRWP) consist of a complex mixture of rubber, and pavement released from tires during use on road surfaces. Subsequent transport of the TRWP into freshwater sediments has raised some concern about the potential adverse effects on aquatic organisms. Previous studies have shown some potential for toxicity for tread particles, however, toxicity studies of TRWP collected from a road simulator system revealed no acute toxicity to green algae, daphnids, or fathead minnows at concentrations up to 10,000 mg/kg under conditions representative of receiving water bodies. In this study, the chronic toxicity of TRWP was evaluated in four aquatic species. Test animals were exposed to whole sediment spiked with TRWP at concentrations up to 10,000 mg/kg sediment or elutriates from spiked sediment. Exposure to TRWP spiked sediment caused mild growth inhibition in Chironomus dilutus but had no adverse effect on growth or reproduction in Hyalella azteca. Exposure to TRWP elutriates resulted in slightly diminished survival in larval Pimephales promelas but had no adverse effect on growth or reproduction in Ceriodaphnia dubia. No other endpoints in these species were affected. These results, together with previous studies demonstrating no acute toxicity of TRWP, indicate that under typical exposure conditions TRWP in sediments pose a low risk of toxicity to aquatic organisms. PMID:23001428

The authors performed a simple experiment to elucidate phase structure within a pervasively fractured welded tuff. Dyed water was infiltrated from a surface pond over a 36 minute period while a geophysical array monitored the wetted region within vertical planes directly beneath. They then excavated the rock mass to a depth of {approximately}5 m and mapped the fracture network and extent of dye staining in a series of horizontal pavements. Near the pond the network was fully stained. Below, the phase structure immediately expanded and with depth, the structure became fragmented and complicated exhibiting evidence of preferential flow, fingers, irregular wetting patterns, and varied behavior at fracture intersections. Limited transient geophysical data suggested that strong vertical pathways form first followed by increased horizontal expansion and connection within the network. These rapid pathways are also the first to drain. Estimates also suggest that the excavation captured from {approximately}10% to 1% or less of the volume of rock interrogated by the infiltration slug and thus the penetration depth could have been quite large.

This paper investigates the phenomenon of excessive pedestrian-induced lateral vibrations as observed on several high-profile footbridges. The vibrations are a consequence of human-structure interaction, in which the forces generated by the pedestrians depend strongly on the vibration of the underlying pavement. An extensive experimental analysis has been carried out to determine the lateral forces generated by pedestrians when walking on a laterally moving treadmill. Two different conditions are investigated; initially the treadmill is fixed and then it is laterally driven in a sinusoidal motion at varying combinations of frequencies (0.33-1.07 Hz) and amplitudes (4.5-48 mm). The component of the pedestrian-induced force which is caused by the laterally moving surface is herewith quantified through equivalent velocity and acceleration proportional coefficients. It is shown that large amplitude lateral vibrations are the results of correlated pedestrian forces in the form of negative damping, with amplitudes that depend on the relationship between the step frequency and the frequency of the lateral movement.

This Rate Training Manual (Textbook) and Nonresident Career Course form a correspondence, self-study package to provide information related to tasks assigned to Builders Third and Second Class. Focus is on constructing, maintaining, and repairing wooden, concrete, and masonry structures, concrete pavement, and waterfront and underwater structures; performing rough and finish carpentry; erecting or repairing waterfront structures, wooden and concrete bridges and trestles; fabricating and erecting forms; mixing, placing, and finishing concrete; laying and setting masonry; and painting or varnishing new and refinished surfaces. The 16 chapters in the text are Construction Administration; Drawings and Specifications; Woodworking Shop and Field Tools; Woodworking: Materials and Methods; Fiber Line, Wire Rope, and Scaffolding; Leveling, Grading, and Excavating; Concrete; Masonry; Light Frame Construction: Floor and Wall; Roof Framing; Exterior Finish; Interior Finish; Plastering; Stuccoing, and Ceramic Tile; Paints and Preservatives; Advanced Base Field Structures; and Heavy Construction. The Nonresident Career Course follows the index. It contains 18 assignment and learning objectives with related sets of teaching items to be answered. Learning objectives and items are based on subject matter or study material in the textbook. (YLB)

We have studied polydimethylsiloxane (PDMS)-in-1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF(6)]) Pickering emulsions stabilized by polystyrene microparticles with different surface chemistry. Surprisingly, in contrast to the consensus originating from oil/water Pickering emulsions in which the solid particles equilibrate at the oil-water droplet interfaces and provide effective stabilization, here the polystyrene microparticles treated with sulfate, aldehyde sulfate, or carboxylate dissociable groups mostly formed monolayer bridges among the oil droplets rather than residing at the oil-ionic liquid interfaces. The bridge formation inhibited individual droplet-droplet coalescence; however, due to low density and large volume (thus the buoyant effect), the aggregated oil droplets actually promoted oil/ionic liquid phase separation and distressed emulsion stability. Systems with binary heterogeneous polystyrene microparticles exhibited similar, even enhanced (in terms of surface chemistry dependence), bridging phenomenon in the PDMS-in-[BMIM][PF(6)] Pickering emulsions. PMID:21840016

The United States is suffering from an aging civil infrastructure crisis. Key to recovery are rapid inspection technologies like that being investigated by the VOTERS project (Versatile Onboard Traffic Embedded Roaming Sensors), which aims to outfit ordinary road vehicles with compact low-cost hardware that enables them to rapidly assess and report the condition of roadways and bridge decks free of driver interaction. A key piece of hardware, and the focus of this paper, is a 24 GHz millimeter-wave radar system that measures the reflectivity of pavement surfaces. To account for the variability of real-world driving, such as changes in height, angle, speed, and temperature, a sensor fusion approach is used that corrects MWR measurements based on data from four additional sensors. The corrected MWR measurements are expected to be useful for various characterization applications, including: material type; deterioration such as cracks and potholes; and surface coverage conditions such as dry, wet, oil, water, and ice. Success at each of these applications is an important step towards achieving the VOTERS objective, however, this paper focuses on surface coverage, as whatever covers the driving surface will be most apparent to the MWR sensor and if not accounted for could significantly limit the accuracy of other applications. Contributions of the paper include findings from static lab tests, which validate the approach and show the effects of height and angle. Further contributions come from lab and in-field dynamic tests, which show the effects of speed and demonstrate that the MWR approach is accurate under city driving conditions.

Coal-tar-based sealcoat products, widely used in the central and eastern U.S. on parking lots, driveways, and even playgrounds, are typically 20-35% coal-tar pitch, a known human carcinogen that contains about 200 polycyclic aromatic hydrocarbon (PAH) compounds. Research continues to identify environmental compartments—including stormwater runoff, lake sediment, soil, house dust, and most recently, air—contaminated by PAHs from coal-tar-based sealcoat and to demonstrate potential risks to biological communities and human health. In many cases, the levels of contamination associated with sealed pavement are striking relative to levels near unsealed pavement: PAH concentrations in air over pavement with freshly applied coal-tar-based sealcoat, for example, were hundreds to thousands of times higher than those in air over unsealed pavement. Even a small amount of sealcoated pavement can be the dominant source of PAHs to sediment in stormwater-retention ponds; proper disposal of such PAH-contaminated sediment can be extremely costly. Several local governments, the District of Columbia, and the State of Washington have banned use of these products, and several national and regional hardware and home-improvement retailers have voluntarily ceased selling them.

OBJECTIVES: This study examined the cross-sectional and longitudinal relationships of illness perceptions, coping, and distress in women with breast cancer. Illness perceptions and coping at baseline and changes in these variables over time served as possible predictors of distress at two follow-up points. DESIGN AND METHODS: Fifty-seven women with breast cancer who participated in a psychosocial aftercare programme completed a questionnaire before the start of the intervention, directly after the end of the intervention, and 1 year after the start of the intervention. Study variables were assessed with the Illness Perception Questionnaire-Revised (illness perceptions), the COPE (coping), and the Hopkins Symptom Check List (distress). RESULTS: Results showed that 43% of variance in distress at baseline was explained by participants' illness perceptions. Cyclical timeline perceptions were the strongest predictor of distress at baseline. Longitudinal data revealed that after the end of the intervention, the intensity of general distress and breast cancer-related emotions had decreased significantly. Partial correlations showed that baseline illness perceptions were unrelated to distress at follow-up. However, changes in illness perceptions (perceptions about the cyclical and chronic timeline and symptoms associated with breast cancer) showed significant associations with distress at both follow-up assessments. Associations of follow-up distress with coping styles were less consistent. CONCLUSIONS: Our results suggest that changes in illness perceptions are related to an improvement or worsening of patients' emotional well-being over time. These findings hold promise for the development of interventions that specifically target patients' representations of their illness. STATEMENT OF CONTRIBUTION: What is already known on this subject? Research has shown that 15%-30% of breast cancer survivors continue to experience elevated distress following treatment. Illness perceptions and coping have been found to contribute to distress in women with breast cancer. What does this study add? Cyclical timeline beliefs affect distress in breast cancer both in cross-sectional and longitudinal analyses. Baseline illness perceptions are less predictive of distress at follow-up than changes in illness perceptions. PMID:23006141

A methodology is proposed to analyze the radiative and thermal exchanges between a small urban neighborhood and the atmosphere based on the use of the thermoradiative model SOLENE and radiometric measurements to optimize the effective values of its constant parameters. Applied to the center of Toulouse, France, the optimization data are building surface temperatures measured with handheld radiometers and a downward-facing pyranometer during one of the intense observation periods of the CAnopy and Particles Interactions in TOulouse Urban Layer (CAPITOUL) experimental campaign. The quality of the simulations is assessed by comparing, without any other model adjustment, the model outputs for two diurnal cycles (1 day in summer and 1 day in winter) against two independent experimental datasets from fixed permanent radiometers and from sensors measuring the solar, infrared and sensible heat fluxes to the atmosphere at the top of a mast 30 m above the roofs. These simulations allow us to further analyze the separate contributions of the different surface classes, roofs, facades and pavement to these fluxes and to compare them with their counterparts observed over a neighborhood of Marseilles city center during a previous experiment. The partition is remarkably similar in Toulouse and Marseilles: 6-7% for the solar radiation, 73-76% for the infrared radiation and 17-20% for the sensible heat flux. The contribution of roofs to the infrared flux appears proportional to their plan area proportion (built density) but not the contributions to the other two fluxes. The contributions of facades to all three fluxes are roughly proportional to their fraction of the total surface area.

Reconstruction of roadways generates large quantities of waste material and requires considerable amounts of aggregate. The recycling of concrete from old deteriorated pavements into aggregates for construction of new pavements reduces disposal costs as well as providing a source of aggregates to replace natural supplies. In this study, recycled coarse and fine aggregates were obtained from a portion of concrete pavement which was removed from Interstate 40 in North Carolina. Various amounts of recycled coarse and fine aggregates were volumerically substituted for natural coarse and fine aggregates of a control mixture. A relatively higher cement factor was used for the control mix, compared to NCDOT standard. The effects on plastic and hardened concrete properties were investigated.

Increasing the HMA base thickness and modifying the HMA mixture properties to improve the resistance to fatigue cracking are among the most popular methods for achieving long-lasting pavements. Such methods are based on the idea of reducing the tensile strain at the bottom of the HMA layer below the Fatigue Endurance Limit (FEL), a level of strain below which no cumulative damage occurs to the HMA mixture. This study investigates the effectiveness of several design strategies involved in long-life, perpetual pavement design. A 3D Finite Element model of the pavement involving a linear viscoelastic constitutive model for HMA materials and non-uniform tire contact stresses is developed using ABAQUS 6.11. The effects of asphalt base course thickness and mixture type, rich binder layer, and aggregate subbase layer are examined. Four asphalt base course mixture types, namely dense graded, polymer modified, high modulus, and standard binder, are studied as a function of the asphalt base course thickness. The result...

The design of pavement snow melting systems is presented based on criteria established by ASHRAE. The heating requirements depends on rate of snow fall, air temperature, relative humidity and wind velocity. Piping materials are either metal or plastic, however, due to corrosion problems, cross-linked polyethylene pipe is now generally used instead of iron. Geothermal energy is supplied to systems through the use of heat pipes, directly from circulating pipes, through a heat exchanger or by allowing water to flow directly over the pavement, by using solar thermal storage. Examples of systems in New Jersey, Wyoming, Virginia, Japan, Argentina, Switzerland and Oregon are presented. Key words: pavement snow melting, geothermal heating, heat pipes, solar storage, Wyoming, Virginia, Japan, Argentina, Klamath Falls.

Welker, Andrea L., James D. Barbis, and Patrick A. Jeffers, 2012. A Side-by-Side Comparison of Pervious Concrete and Porous Asphalt. Journal of the American Water Resources Association (JAWRA) 48(4): 809-819. DOI: 10.1111/j.1752-1688.2012.00654.x Abstract:- This article compares the performance of two permeable pavements, pervious concrete and porous asphalt, that were installed side-by-side in fall 2007. Because the pavements are located directly adjacent to one another, they experience the same vehicle loads, precipitation, and pollution loads. These permeable pavements are part of an infiltration stormwater control measure (SCM). This article focuses on the comparison of water quality parameters, maintenance and durability, and user perception. Eleven different water quality parameters ...

As shown by strains measured on full scale experimental aircraft structures, traffic of slow-moving multiple loads leads to asymmetric transverse strains that can be higher than longitudinal strains at the bottom of asphalt pavement layers. To analyze this effect, a model and a software called ViscoRoute have been developed. In these tools, the structure is represented by a multilayered half-space, the thermo-viscoelastic behaviour of asphalt layers is accounted by the Huet-Sayegh rheological law and loads are assumed to move at constant speed. First, the paper presents a comparison of results obtained with ViscoRoute to results stemming from the specialized literature. For thick asphalt pavement and several configurations of moving loads, other ViscoRoute simulations confirm that it is necessary to incorporate viscoelastic effects in the modelling to well predict the pavement behaviour and to anticipate possible damages in the structure.

Asphalt overlays provide an economical means for treating deteriorated pavements. Thin bonded overlay (TBO) systems have become popular options for pavement rehabilitation. In addition to functional improvements, these systems ensure a high degree of waterproofing benefits. Conventional asphalt concrete fracture tests were developed for pavements with homogeneous asphalt concrete mixtures, and typically their thicknesses exceed 50?mm (2?inch). The use of spray paver technology for construction of TBO leads to continuously varying asphalt binder content, up to approximately one-third of the layer thickness. Commonly utilized fracture test geometries for asphalt concrete include the single-edge notched beam, SEN[B], the disk-shaped compact tension, DC[T], and the semi-circular bend, SC[B]. T...

Asphalt overlays provide an economical means for treating deteriorated pavements. Thin bonded overlay (TBO) systems have become popular options for pavement rehabilitation. In addition to functional improvements, these systems ensure a high degree of waterproofing benefits. Conventional asphalt concrete fracture tests were developed for pavements with homogeneous asphalt concrete mixtures, and typically their thicknesses exceed 50 mm (2 inch). The use of spray paver technology for construction of TBO leads to continuously varying asphalt binder content, up to approximately one-third of the layer thickness. Commonly utilized fracture test geometries for asphalt concrete include the single-edge notched beam, SEN[B], the disk-shaped compact tension, DC[T], and the semi-circular bend, SC[B]. T...

Due to climate change, cities need to adapt to changing rainfall and rainwater run-off dynamics. In order to get an appropriate data base for an corresponding process based water balance model for pavements, we had to improve the measuring method for urban run-off dynamics. We tinkered an old tipping bucket to a digital balance, called that a weighable tipping bucket (WTB) and were able to measure run-off from our paved lysimeters with an substantially increased temporal and volume resolution. Traditional tipping buckets (TB) have a volume resolution, capable to quantify the highest intensities in a range of expected flows. This results in varying temporal resolutions for varying flow intensities, especially in low resolutions for small flow events. Therefore, their applicability for run-off measurements and other hydrological process studies is limited, especially when dynamics of both small and storm events shall be described. This paper introduces the device set up and an according data processing concept. The improved volume and temporal resolution of the WTB are demonstrated. The impact of that increased resolution on our understanding of run-off dynamics from paved urban soils are discussed, exemplary for the run-off and the surface storage of a paved urban soil. The study was conducted on a permeably paved lysimeter situated in Berlin, Germany. Referring to the paved surface, the TB has a resolution of 0.1 mm, while the WTB has a resolution of 0.0005 mm. The temporal resolution of the WTB is 3 s, the TB detects individual tippings with 0.4 s between them. Therefore, the data processing concept combines both the benefits of the balance and the TB. During a five months period (July to November 2009) 154 rain events were detected. Accordingly, the TB and WTB detected 47 and 121 run-off events. The total run-off was 79.6mm measured by the WTB which was 11% higher than detected by the TB. 95% of that difference can be appointed to water, which evaporated from the TB. To derive a surface storage estimation, we analyzed the WTB and TB data for rain events without run-off. According to WTB data, the surface storage of the permeable pavement is 1.7 mm, while using TB data leads to an overestimation of 47% due to low volume resolution of the TB. Combining traditional TB with modern, fast, high resolution digital balances offers the opportunity to upgrade existing TB systems in order to improve their volume detection limit and their temporal resolution, which is of great advantage for the synchronization of water balance component measurements and the investigation of hydrological processes. Details can be found in Hydrol. Earth Syst. Sci., 15, 1379-1386, 2011 www.hydrol-earth-syst-sci.net/15/1379/2011/ doi:10.5194/hess-15-1379-2011

In regions where studded tyres and traction material are used during winter, e.g. the Nordic countries, northern part of USA, Canada, and Japan, mechanically generated particles from traffic are the main reason for high particle mass concentrations in busy street and road environments. In many Nordic municipalities the European environmental quality standard for inhalable particles (PM(10)) is exceeded due to these particles. In this study, particles from the wear of studded and studless friction tyres on two pavements and traction sanding were generated using a road simulator. The particles were characterized using particle sizers, Particle Induced X-Ray Emission Analysis and electron microscopy. Cell studies were conducted on particles sampled from the tests with studded tyres and compared with street environment, diesel exhaust and subway PM(10), respectively. The results show that in the road simulator, where resuspension is minimized, studded tyres produce tens of times more particles than friction tyres. Chemical analysis of the sampled particles shows that the generated wear particles consist almost entirely of minerals from the pavement stone material, but also that Sulfur is enriched for the submicron particles and that Zink is enriched for friction tyres for all particles sizes. The chemical data can be used for source identification and apportionment in urban aerosol studies. A mode of ultra-fine particles was also present and is hypothesised to originate in the tyres. Further, traction material properties affect PM(10) emission. The inflammatory potential of the particles from wear of pavements seems to depend on type of pavement and can be at least as potent as diesel exhaust particles. The results imply that there is a need and a good potential to reduce particle emission from pavement wear and winter time road and street operation by adjusting both studded tyre use as well as pavement and traction material properties. PMID:18258284

An 8-year-old Brown Swiss dairy cow was presented with unilateral epistaxis and mild inspiratory stridor. At that time endoscopic examination revealed a smooth-surfaced mass within the left nasal cavity. Biopsy samples were collected and a diagnosis of fibrosarcoma was made. Eighteen months later the animal developed severe respiratory distress that led to difficulties in feeding and consequently to emaciation and a dramatic drop in milk production. The cow was humanely destroyed and submitted for post-mortem examination. The head was subject to further investigation by radiography, computed tomography and magnetic resonance imaging. These techniques revealed a non-infiltrative, well-circumscribed mass of both radiodense and heterogeneously intense structures. Histopathological examination revealed a mass consisting of well-differentiated and interlacing bone trabeculae lined by osteoblasts and multinucleated osteoclasts. In contrast to the initial diagnosis, the later diagnostic approaches supported the diagnosis of osteoma. PMID:19539951

Elastohydrodynamic (EHD) film thicknesses have been measured, by means of an X-ray technique, under conditions that closely simulate the ball-race contact in advanced turbine engine thrust bearings. The experiments were conducted with a rolling-disk machine using disks which yield a contact zone similar to that in the actual bearing. Both the rolling and spinning motions of the ball relative to the race were simulated by the apparatus. Four lubricants were evaluated at temperatures to 600 F and maximum Hertz stresses to 350,000 psi. The X-ray film thickness data correlated well with observations of surface distress (or lack thereof) in full-scale bearing tests with the same lubricants under similar conditions of temperature and load. The predicted variation of film thickness with speed and viscosity as verified, although the magnitude of measured film thickness was generally one-half to one-third of predicted values. An effect of stress greater than predicted was consistently observed in the higher stress range.

This study presents the results of evaluating changes in properties of road sediment fractionated particles at the source (dry pavement), during transport (highway runoff) and after deposition (dry detention basin). A total of 38 solid particle samples were collected from paved surface, highway runoff, and from three locations within detention basins. Each sample was size-fractionated ranging from 38?m to 1000?m. Key results were that: (i) less than 2% of total particle mass in four vacuumed solid samples was associated with the sediments, (ii) based on number concentrations more than 90% of particles from all sources were smaller than 38?m, (iii) the densities of fractionated particles were generally within the range from 1.5 to 2.2g/cm(3); (iv) all collected particles were predicted to resist aggregation in solution with a typical measure of surface potential, the zeta potential, typically ranging from -15 to -30mV, (v) metal concentrations increased with decreasing particle size for vacuumed samples from the highway shoulder and parking lot, however, size dependent trends in metal concentrations were less apparent in centrifuged highway runoff samples and detention basin sediment samples; (vi) the distributions of metal mass across sieved size fractions generally followed patterns of particle mass distribution in which less than 10% of the total Cu, Pb, and Zn mass was associated with particles <38?m; (vii) metal mass distributions tended toward increasing metal fractions in finer particle fractions along a gradient from the inlet to the outlet of the detention basins; and (viii) individual particle morphology (1

Abstract in portuguese Nas proximidades da Cerâmica Guaraú, localizada a sudoeste da cidade de Salto, Estado de São Paulo, dois afloramentos de granito, distantes algumas dezenas de metros um do outro, exibem superfícies estriadas neopaleozóicas. Essas superfícies estão em contato com diamictitos do Subgrupo Itararé. As estrias correspondem a sulcos subparalelos com espaçamento e profundidade milimétrica, possuindo uma direção média de N48°W e mergulhos variando entre 12° e 42° (more) para SE. As feições observadas e a sua associação com diamictitos indicam uma origem por abrasão glacial devido ao movimento de massas de gelo de sudeste para noroeste. A aproximadamente 1,8 km a este da cidade de Salto foi encontrado, no topo de afloramentos de granito, material inconsolidado contendo abundantes clastos de quartzito facetados e estriados. Esses clastos foram interpretados como vestígios de um pavimento de castos. Abstract in english Near Guaraú Ceramic, localized southwest of Salto city in the State of São Paulo, two granite outcrops, distant some tens of meters from each other, display Neopaleozoic striated surfaces. These surfaces are in contact with diamictites from the Itararé Subgroup. The striae correspond to sub parallel grooves with millimetric spacing and depth, oriented about N48E and dipping 12° to 42° towards SE. Observed features and association with diamictites indicate an origin b (more) y glacial abrasion due to ice movement from southeast towards northwest. About 1.8 km east of Salto, unconsolidated material containing flat-iron-shaped and striated clasts was found on top of granite outcrops, interpreted as clast pavement remains.

Micropollutants, such as pesticides, personal care products, veterinary and human pharmaceuticals, pose a possible threat to human and ecological health. Humans and ecosystems may be exposed to these chemicals via the water system. Catchment models can be used to optimise management in view of risk reduction of the chemicals. Along the trajectory of science to practice a number of catchment models are available that simulate the fate and transport of micropollutants. They range from physically-based fully-coupled soil, groundwater, and surface water models, over empirical management models, to purely statistical database-driven models. For assessing effects on ecosystems, models need to be able to predict the observed highly dynamic behaviour of pesticide concentrations in the surface water, since adverse effects will be determined by the number, intensity and frequency of ecological threshold exceedances. For assessing effects on humans, models need to predict the dilution between areas where the pesticide is released and the location of the drinking water intake, sometimes tens or hundreds of kilometres further downstream. We adapted management models to simulate dynamic pesticide behaviour and fate at the catchment scale. The models were also used to illustrate the effects of specific management options on risk reduction and to derive the dominant sources of pollutants in a catchment area. The results show that the concentrations of pesticides in river systems are attributed to (1) fast flow over and in soils or pavements, and to (2) point sources. Therefore, future models for improved estimation of chemical fate at the catchment scale need a combination of stochastic source characterisation, higher spatial resolution and reduced complexity of the mathematical description of fast flow processes. This will be illustrated by recent developments in model simplification coupled to increased spatial detail.

Ballasted tracks generally need periodical maintenance work, because they are gradually destroyed by repeated trainloads. Enormous expenditure is spent, therefore, to maintain tracks under good conditions. As an alternative to ballasted tracks, concrete slab tracks are widely used in Japan. However, the noise levels on slab tracks are higher than on ballasted tracks. In order to solve this problem, the authors proposed a low noise solid bed track on asphalt pavement for new railway lines, and carried out performance tests. This paper describes the structure of solid bed track on asphalt pavement and results of performance tests.   

The asphalt pavement is regarded as a multilayered elastic half space axisymmetrical body. By introducing the relationship between material characteristics and temperature into the fundamental equations of thermoelasticity and using mathematic methods of Laplace and Hankel integral transformation, the stiffness matrix for a layer is derived firstly. Then the global stiffness matrix is established for multilayered elastic half space using the finite element concepts in which layers are completely contacted. Therefore, explicit solution for thermal stresses of the asphalt pavement is obtained from the solution of the algebra equation formed by global stiffness matrix and the inverse Hankel and Laplace integral transformation. Because the elements of matrix do not include positive exponential...

Rationale: Endothelin-1 (ET-1) is increased in patients with high-altitude pulmonary edema and acute respiratory distress syndrome, and these patients have decreased alveolar fluid reabsorption (AFR).

CHARLIER C., PAUWELS E., LECHNER L., SPITTAELS H., BOURGOIS J., DE BOURDEAUDHUIJ I. & VAN HOOF E. (2012) European Journal of Cancer Care Physical activity levels and supportive care needs for physical activity among breast cancer survivors with different psychosocial profiles: a cluster-analytical approach The transition from breast cancer patient to survivor is associated with many treatment-related and psychosocial factors, which can influence health behaviour and associated needs. First, this study aimed to identify clusters of treatment-related and psychosocial factors among breast cancer survivors. Second, clusters' physical activity levels and care needs for physical activity were evaluated. Breast cancer survivors (n= 440; 52 ± 8 years) (3 weeks to 6 months post treatment) completed self-reports on physical and psychological symptoms; illness representations; social support and coping; physical activity and care needs for physical activity. Analyses identified four clusters: (1) a low distress-active approach group; (2) a low distress-resigned approach group; (3) a high distress-active approach group; and (4) a high distress-emotional approach group. Physical activity levels were higher in the low distress groups than in the high distress-emotional approach group. However, women with low distress and an active approach reported equal care needs for physical activity than women with high distress and an emotional approach. These findings suggest that care needs for physical activity are unrelated to distress and actual physical activity levels. The results emphasise the importance of screening for needs and provide a framework supporting the referral of breast cancer survivors to tailored interventions. PMID:22591050

Objective: Short screening instruments have been suggested to improve the detection of psychological symptoms. We examined the accuracy of the Danish version of the 'Distress Thermometer'. Methods: Between October 2008 and October 2009, 426 women with newly diagnosed primary breast cancer who were operated at the Breast Surgery Clinic of the Rigshospitalet, Copenhagen, were eligible for this study. Of these, 357 participated (84%) and 333 completed a questionnaire. The distress thermometer was evaluated against the 'hospital anxiety and depression scale' (HADS). We also examined the women's wish for referral for psychological support. Results: A cut-off score of 6 vs 7 (low:¿6, high:¿7) on the distress thermometer was optimal for confirming distress, with a sensitivity of 42%, a specificity of 93%, a positive predictive value (PPV) of 78% and a negative predictive value (NPV) of 73%. A cut-off score of 2 vs 3 was optimal for screening, with a sensitivity of 99%, a specificity of 36%, a PPV of 47% and a NPV of99%. Of those who were distressed using the cut-off score of 2 vs 3 on the distress thermometer, 17% (n = 41) wished to be referred for psychological support and 57% (n = 140) potentially wanted a later referral. Conclusion: The distress thermometer performed satisfactorily relative to the HADS in detecting distress in our study. A screening procedure in which application of the distress thermometer is a first step could be useful for identifying persons in need of support. Copyright © 2011 John Wiley & Sons, Ltd.

Objectives: This study examined psychological distress in older people receiving home nursing care. The influence of risk factors and personal resources on their perceived psychological distress was also examined. Method: A linear regression analysis was applied in a cross-sectional sample of 214 patients aged 75 years and older. Psychological distress was measured using the General Health Questionnaire (GHQ). The independent variables were sex, education, age, living arrangement, household composition, reported illnesses, Barthel ADL Index, self-rated health, Subjective Health Complaints, Clinical Dementia Rating Scale, Sense of Coherence and Revised Social Provision Scale. Results: Of the 214 participants, 23 (10.7%) reported experiencing psychological distress using a cutoff point of 4 ...

Abstract in portuguese Bagres podem apresentar dois órgãos sonoros: o espinho peitoral para o som peitoral ou estridulatório e o músculo sonoro da bexiga natatória. O objetivo deste trabalho foi caracterizar a produção de som no bagre Iheringichthys labrosus. Essa espécie emite dois sons diferentes, o som peitoral ou estridulatório (655,8 + 230 Hz) que consiste numa série de pulsos, e o som de tamboril (220 + 46 Hz) que é composto por sinais harmônicos de pulso simples. O som peitor (more) al é emitido com o movimento do espinho da nadadeira peitoral. A base do espinho possui um processo dorsal que suporta uma série de cristas na sua superfície lateroventral, e ao pressionar as cristas contra o sulco (com uma superfície rugosa não especializada) durante o movimento de abertura da nadadeira, se produz uma série de pulsos curtos. O som de tamboril é produzido por um músculo sônico extrínseco, originado em um tendão plano preso ao processo transversal da quarta vértebra e inserido nas superfícies rostral e ventral da bexiga natatória. Os sons são emitidos por ambos os mecanismos em situação de estresse, a qual foi induzida através da manipulação dos peixes em um tanque no laboratório, enquanto os sons eram gravados. Nossos resultados indicam que o bagre emite primeiro o som peitoral e em seguida o som de tamboril. Também foi observada a produção simultânea dos sons estridulatório e de tamboril. O som de tamboril mostra uma frequência dominante mais baixa do que o som peitoral, e também apresenta um grau menor de modulação de frequência dominante. Isso pode estar relacionado com um som de cortejo, como verificado em outros peixes teleósteos. Outro comportamento observado nessa espécie de bagre é a capacidade de travar o espinho peitoral. Essa reação foi observada imediatamente antes da produção do som. Como descrevem outros autores, nossos resultados sugerem que em I. labrosus o som de estridulação e de tamboril funcionam como uma chamada de alarme. Abstract in english Catfishes may have two sonic organs: pectoral spines for stridulation and swimbladder drumming muscles. The aim of this study was to characterize the sound production of the catfish Iheringichthys labrosus. The I. labrosus male and female emits two different types of sounds: stridulatory sounds (655.8 + 230 Hz) consisting of a train of pulses, and drumming sounds (220 + 46 Hz), which are composed of single-pulse harmonic signals. Stridulatory sounds are emitted during abd (more) uction of the pectoral spine. At the base of the spine there is a dorsal process that bears a series of ridges on its latero-ventral surface, and by pressing the ridges against the groove (with an unspecialized rough surface) during a fin sweep, the animal produce a series of short pulses. Drumming sound is produced by an extrinsic sonic muscle, originated on a flat tendon of the transverse process of the fourth vertebra and inserted on the rostral and ventral surface of the swimbladder. The sounds emitted by both mechanisms are emitted in distress situation. Distress was induced by manipulating fish in a laboratory tank while sounds were recorded. Our results indicate that the catfish initially emits a stridulatory sound, which is followed by a drumming sound. Simultaneous production of stridulatory and drumming sounds was also observed. The catfish drumming sounds were lower in dominant frequency than stridulatory sounds, and also exhibited a small degree of dominant frequency modulation. Another behaviour observed in this catfish was the pectoral spine locking. This reaction was always observed before the distress sound production. Like other authors outline, our results suggest that in the catfish I. labrosus stridulatory and drumming sounds may function primarily as a distress call.

We previously reported that a human analogue of pulmonary surfactant protein-C (SP-C), SP-CL16(6—28), with 23 residues was the most active analogue in a reconstituted lipid mixture and had the shortest chain among the poly-leucine-analogues examined. There has been little research on the chemical components of synthetic lung surfactants (SLSs). In the present study, we attempted to compare SLS with various phospholipids in surface activity. That is, SP-CL16(6—28) plus various phosphatidylglycerols (PG) were tested for surface activity in a Langmuir–Wilhelmy surface balance (WSB) apparatus and pulsating bubble surfactmeter (PBS). Further, SLSs were examined for biological properties using an animal model of surfactant deficiency, infant respiratory distress syndrome (IRDS), in vivo. Palmitoyl-oleoyl-phosphatidylglycerol (POPG)-SLS exhibited minimum and maximum surface tensions of 1.7 mN/m and 28.6 mN/m in WSB and 8.5 mN/m and 36.2 mN/m in PBS, respectively. Moreover, in the IRDS model, POPG-SLS remarkably improved the lung volume (LV) of a premature lagomorph fetus at LV30 cmH2O and LV5 cmH2O. That is, a significant improvement equal to the LV of a full-term fetus was observed. The level of LV exhibited respiratory improvement equivalent to surfactant-TA. SLS seemed comparable in surface activity with Surfacten® (Surfactant-TA), a modified surfactant preparation which has been used for the treatment of RDS.   

Various oxidative stress and histopathological biomarkers in gill tissues of Nile tilapia Oreochromis niloticus were investigated. Fish were collected from four sites that differ in their extent of pollution load, including heavy metals: the southeast basin (SEB), main basin (MB), and northwest basin (NWB) of Lake Mariut; and Boughaz El-Maadiya, a channel in Lake Edku. The oxidative stress biomarkers that were analyzed included lipid peroxidation (LPO), superoxide dismutase (SOD), catalase (CAT), and glutathione redox cycle enzymes (glutathione peroxidase [GPx] and glutathione reductase [GR]). Levels of reduced glutathione (GSH) were also evaluated. Gill morphology was analyzed by light microscopy and scanning electron microscopy (SEM). Gill LPO was significantly higher in gill tissues of fish collected from the more heavily contaminated MB (40.0%) and NWB (51.4%) sites than in gill samples from the less-contaminated (reference) site, the SEB. Gill LPO in fish from Lake Edku was intermediate but was not significantly higher (17.1%) than the reference. The activities of antioxidant enzymes and the redox-sensitive thiol compound GSH were significantly lower in gill samples from the disturbed sites than in samples from the reference site. Specifically, SOD in MB, NWB, and Lake Edku samples; CAT and GPx in NWB samples; and GR activity and GSH content in MB and NWB samples were lower than those in SEB samples. In most cases, gill tissues from Lake Edku fish had intermediate levels of antioxidants. The main histopathological alterations observed in gills were epithelial lifting, hyperplasia and hypertrophy of the respiratory epithelium, lamellar fusion, and aneurysms. In addition, SEM results demonstrated transformation of the surface structure of epithelial pavement cells. Pathological reactions in the gills of Nile tilapia were most severe at the MB and NWB sites. Our findings suggest that Nile tilapia responded differently according to the environmental stress index in each sampling area. This study is the first to report gill oxidative stress and histopathologies in Nile tilapia from Egyptian aquatic environments. PMID:22897228

Stormwater issues have been resolved at the Lawrence Technological University in Southfield, Michigan by constructing a new vegetated green roof and bioswale. Southfield, Michigan faces significant stormwater management issues. The abundance of sealed surfaces, pavements, and rooftops have contributed to stormwater and environmental problems that are prevalent in urban areas. Unimpeded flow of stormwater were contributing to flash flood conditions, erosion, and a flow of sediments into the ecosystems of the Rouge River. The construction of a green roof demonstrated the University's commitment to the City of Southfield to improve stormwater management, and served as an educational tool in sustainable design for students in architecture, design, engineering and management programs. With its efficient use of renewable resources, the new A. Alfred Taubman Student Services Center symbolizes sustainable design in action. In its commitment to sustainable design, the University called in the partner firms of Harley Ellis Devereaux, Spectrum Strategies and GreenWorks Studio to help develop a two-part solution. First, a Strategic Campus Master Plan was developed for the 125-acre campus. The purpose was to align campus facilities, infrastructure, and the environment with the University's academic and administrative plan, capital planning processes and maintenance operations. A stormwater master plan was then developed that focused on innovative stormwater infiltration strategies as part of the larger strategic undertaking. The new Student Services Center was chosen as the first building for implementing the new plan. A concrete and grass area was transformed into an interesting and inspiring place that is friendly to the environment. The building's green roof was one opportunity to address greening issues. The green roof will capture about 60 per cent of the rainfall from a typical rain event. The remainder of the rainfall will be captured and reused or infiltrated into the ground and cleaned. 1 fig.

Desirable properties of asphalt pavements include high stability, flexibility, and durability. In order to achieve these properties, the asphalt should bind well with mineral aggregates and the properties of the resulting asphalt concrete should change as slowly as possible during service life. The interaction of water and asphaltic concrete under particular circumstances may cause stripping or loss of adhesion and consequential detachment of the asphalt from the aggregate. Use of aggregates treated with these polymer emulsions resulted in a much stronger bond at the asphalt-aggregate interface. Scanning electron microscope studies showed that a thin polymer film covers the aggregate surface. Ethylene-vinyl acetate copolymer resin 460, ethylene-vinyl acetate copolymer resin 240, styrene butadiene copolymer, cis-1,4-polybutadiene copolymer, and polyethylene were tested as additives. The effect of these on the resistance to permanent deformation and dynamic stiffness is described in this study. The chemical changes that occurred during weathering were also addressed. The effect of oxidation on aged asphalt was determined by measuring the change in infrared absorption with time of exposure. Antioxidants which are capable of decomposing peroxides were found to extend the durability of the asphalt. By observing the concentration of peroxy radicals during the course of a chemical process as indicated by electron spin resonance peak intensity, it was possible to obtain quantitative information on the interaction of antioxidants with peroxy radicals. Indications were obtained that antioxidants are not effective in reducing the brittleness of asphalt upon aging. The effect of six plasticizers on thermal and mechanical properties of asphalt was studied. In general, use of plasticizers resulted in lowered rigidity, increased ductility and increased toughness. Tricresyl phosphate was the most effective.

Paper presented at the 21st Annual South African Transport Conference 15 - 18 July 2002 "Towards building capacity and accelerating delivery", CSIR International Convention Centre, Pretoria, South Africa. , The use of foamed bitumen treated materials in the construction of pavement layers is increasing...

A Three-dimensional (3D) finite element (FE) model was developed to calculate the temperature of a pavement located in Northeast of Portugal. A case study was developed to validate the model. Input data to the model were the hourly values for solar radiation, air temperature and mean daily values of...

Prime and tack coats have a purpose in the pavement construction process, yet many times they are misused or eliminated during the project. While most of the time no harm appears to occur to the roadway, technical guidance is warranted to assure appropria...

The PhD thesis focuses on the performance assessment of permeable pavement systems incorporating ground source heat pumps (GSHP). The relatively high variability of temperature in these systems allows for the survival of pathogenic organisms within the sub?base. Salmonella sp, Escherichia coli, Ente...

We present a workflow to acquire and create a 1.2 Gipapixel high-resolution outcrop panorama of a polished limestone pavement on the Western flank of Jabal Shams in the Oman Mountains. The outcrop panorama serves as a basemap to integrate structural, microstructural and geochemical investigations in...

Environment preservation associated to economic issues have led recycling to be a prime solution for pavement maintenance/rehabilitation. The present work focuses on the analysis of a rehabilitation project that included a recycled base course with cement. The operations involved cold “in situ” recy...

Weeds on pavements in urban areas are unwanted mainly because they cause an untidy appearance or sometimes structural damage. Glyphosate has been the principal weed control method for years, but policies in several European towns have changed to lower dependence on herbicides. Instead, less effectiv...

This paper provides an overview of the asphalt rubber interlayer benefits on reflective crack retardation in flexible pavement preservation and rehabilitation strategies. These interlayers are known in California as asphalt rubber absorbing membrane interlayers (SAMI-R) or as asphalt rubber aggregat...

Asphalt rubber mixtures are one of the most promising techniques to extend the service life of asphalt pavement overlays. Asphalt rubber binder is composed of crumb rubber from reclaimed tires and conventional asphalt. The asphalt rubber binder can be obtained through wet process in two different sy...

Asphalt modified with crumb rubber has been used to produce asphalt rubber mixtures for pavement overlays subjected to heavy loads and high temperatures. Under severe conditions, these mixtures are capable of resisting permanent deformations, having an extended fatigue life and resisting crack propa...

Portuguese Foundation for Science and Technology (FCT) in the scope of the Strategic Project UI 4047 2011?2012 , Building a road pavement requires large amounts of constituent materials, whose extraction can lead to the devastation of natural resources and causes negative impacts on the environment. As...

Regardless of how well conceived a pavement management system (PMS) is, unless well implemented and accepted by the end user its benefits cannot be realized. This paper seeks to estimate the present status of implementation within the U.S. Air Force of th...

Non-point-source pollution is a major source of ecological impairment in urban stream systems. Recent work suggests that coal-tar pavement sealants, used extensively to protect parking areas, may be contributing a large portion of the polycyclic aromatic hydrocarbon (PAH) loading seen in urban stream sediments. The hypothesis that dried coal-tar pavement sealant flake could alter the macroinvertebrate communities native to streams in Austin, TX was tested using a controlled outdoor laboratory type approach. The treatment groups were: control, low, medium, and high with total PAH concentrations (TPAH = sum of 16 EPA priority pollutant PAHs) of 0.1, 7.5, 18.4, & 300 mg/kg respectively. The low, medium, and high treatments were created via the addition of dried coal-tar pavement sealant to a sterile soil. At the start of the 24-day exposure, sediment from a minimally impacted local reference site containing a community of live sediment-dwelling benthic macroinvertebrates was added to each replicate. An exposure-dependent response was found for several stream health measures and for several individual taxa. There were community differences in abundance (P = 0.0004) and richness (P < 0.0001) between treatments in addition to specific taxa responses, displaying a clear negative relationship with the amount of coal-tar sealant flake. These results support the hypothesis that coal-tar pavement sealants contain bioavailable PAHs that may harm aquatic environments. PMID:19913343

Monomers and resins used in the foundry industry are being investigated for use with locally available aggregates for making polymer concrete for rapid repairs of concrete pavements and runways. The polymer concrete has the ability of setting in a wide ra...

A composition for use as a base course in a pavement construction is prepared by prereacting uncompacted incinerator ash with 2-10% by weight lime or 2-10% by weight of a 2:3 lime:fly ash mixture for several days and then adding 2-10% by weight lime and 20-25% by weight water to the composition before compaction.

Uute heliplaatide tutvustus: Moby "Play", Hurricane #1 "Only The Strongest Will Survive", Vonda Shepard "Songs From Ally McBeal" ja "By 7:30", Incognito "No Time Like The Future", Pretenders "Viva El Amor!", Village People "We Want You - Greatest Hits", Pavement "Terror Twilight"

The effect of dowel bar looseness on the joint load transfer efficiency using Falling Weight Deflectometer is the subject of this paper. The mechanism of dynamic load transfer at transverse joints of Jointed Plain Concrete Pavement is examined using nonlinear 3D finite element analysis.

Contaminated black tarry materials was treated thermally and converted to a material with properties similar to petroleum-based asphalt. This property-improved material was then used as a binder to enclose contaminated concrete debris and soil in the solidification/stabilization process. The final product can be used for medium traffic pavement. 9 refs., 5 tabs.

The effect of longitudinal rib arrangement, mainly the spacing between a main girder web and a longitudinal rib, on deformation of asphalt pavement and fatigue of welds was studied for an orthotropic steel deck bridge. The full-scale model with asphalt pavement prepared by modifying a standard orthotropic steel deck box girder for urban expressways was tested by cyclic loading tests and fatigue tests. The cross sectional strain of the deck plate and pavement was dependent on the spacing except the case where the distance between the main web and wheel position was larger than 60 cm. The larger distance and narrower spacing were preferable to prolong the fatigue life of welds of the longitudinal ribs positioned nearest the main web, the larger one and wider one to protect the top of vertical stiffeners from fatigue damages, and the larger one and narrower one for fatigues of both pavement and steel members near the main web. As a result, the spacing could be extended in the case where a traffic load position was arranged away from the main web. 17 refs., 21 figs., 4 tabs.

Upon chronic UV treatment pavement cell expansion in Arabidopsis leaves is reduced, implying alterations in symplastic and apoplastic properties of the epidermal cells. In this study, the effect of UV radiation on microtubule patterning is analysed, as microtubules are thought to serve as guiding ra...

This paper describes the results of a study aiming the evaluation of pavement performance improvement by using a polymer modified bitumen as binder. Two dense graded bituminous mixtures were produced in laboratory. The first one was produced with conventional bitumen and the second one with polymer-...

The present study aims at the investigation of the relationship between distress and job performance of industrial workers. The sample consisted of 500 workers of public and private sectors. CMI Health Questionnaire and Performance Appraisal Scale (PAS) were used to measure the level of distress and...

Although exposure-based treatments appear to be efficacious for the treatment of anxiety-related disorders, many individuals experience a renewal of the original fear response at follow-up. In an effort to prevent fear renewal, researchers have begun to use exposure of the conditioned stimulus in different contexts during extinction. Although studies continue to accumulate, showing that conducting exposure in multiple contexts buffers against the renewal of distress responses to fear-relevant stimuli, it remains unclear how conducting exposure in multiple contexts affects the renewal of distress responses to disgust-relevant stimuli. In the present study, participants (N = 52) were randomized to repeated presentations of disgust stimuli (vomiting in a toilet) in a single context or multiple contexts. Results revealed that those in the single context condition reported less distress after the exposure manipulation compared with the multiple context condition. Although there were no significant group differences in distress toward a novel disgust stimulus, the single context condition reported greater distress renewal than the multiple context condition. Furthermore, individuals in the multiple context condition showed significant reductions in distress at 1-week follow-up whereas distress in the single context condition remained stable. Subsequent analyses also provided moderate evidence for an effect of the disgust context manipulation on physiological arousal and disgust propensity, but not disgust-related behavioral avoidance. These findings offer preliminary evidence that renewal of distress toward disgust cues can be attenuated by conducting extinction in multiple contexts. (Contains 1 note, 1 table and 4 figures.)

This study examines associations between psychological distress and alcohol and drug use across the first five years of raising a child and parenting quality at child age six for 185 adolescent mothers. Overall, alcohol and other drug use in this sample was relatively low, but drug use was associated with more mother-reported unrealistic expectations of child behavior and more attributions of child intent to annoy parent by misbehaving. Maternal psychological distress was associated with maternal reports of negative control (yelling, pushing, spanking, etc.), and alcohol use moderated the association between psychological distress and negative control. At low levels of alcohol use, more maternal distress was associated with greater negative control; at higher levels of alcohol use, maternal distress was not related to negative control, but the absolute level of negative control was similar to that reported by more distressed mothers. Neither psychological distress nor alcohol and other drug use were related to maternal behavior during an interaction task. Overall, much stronger associations with parenting outcomes were found for an index of maternal vocabulary, compared with maternal psychological distress or maternal alcohol and other drug use. PMID:11333005

This paper suggests a motive for bank mergers that goes beyond alleged and typically unverifiable scale economies: preemtive resolution of banks´ financial distress. Such "distress mergers" can be a significant motivation for mergers because they can foster reorganizations, realize diversification g...

Individuals in distress emit audible vocalizations to either warn or inform conspecifics. The Indian short-nosed fruit bat, Cynopterus sphinx, emits distress calls soon after becoming entangled in mist nets, which appear to attract conspecifics. Phase I of these distress calls is longer and louder, and includes a secondary peak, compared to phase II. Activity-dependent expression of egr-1 was examined in free-ranging C. sphinx following the emissions and responses to a distress call. We found that the level of expression of egr-1 was higher in bats that emitted a distress call, in adults that responded, and in pups than in silent bats. Up-regulated cDNA was amplified to identify the target gene (TOE1) of the protein Egr-1. The observed expression pattern Toe1 was similar to that of egr-1. ...

Alcohol dependence is a chronic relapsing disorder similar to other major psychiatry disorders. Alcoholism is considered to be stressful to the family members. This study attempted to examine the behaviors family members report more distressful in frequency and also in their severities. Family members, mostly spouses of fifty males with alcohol dependence were interviewed for the behaviors which they considered distressful. Scale for Assessment of Family Distress (SAFD) for alcoholism was used to assess the frequency and severity of the distressing behaviors. Family members of all the patients (100%) reported behaviors like excessive spending and disturbance of peace at home as distressful. With regard to severity, in addition to the above two behaviors, does not working and earning, not t...

Abstract in english Increased pulmonary vascular resistance in preterm newborn infants with respiratory distress syndrome is suggested, and endothelin-1 plays an important role in pulmonary vascular reactivity in newborns. We determined umbilical cord blood and neonatal (second sample) levels of endothelin-1 in 18 preterm newborns with respiratory distress syndrome who had no clinical or echocardiographic diagnosis of pulmonary hypertension and 22 without respiratory distress syndrome (gesta (more) tional ages: 31.4 ± 1.6 and 29.3 ± 2.3 weeks, respectively). Umbilical cord blood and a second blood sample taken 18 to 40 h after birth were used for endothelin-1 determination by enzyme immunoassay. Median umbilical cord blood endothelin-1 levels were similar in both groups (control: 10.9 and respiratory distress syndrome: 11.4 pg/mL) and were significantly higher than in the second sample (control: 1.7 pg/mL and respiratory distress syndrome: 3.5 pg/mL, P