bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Prediction of Pavement Ride Quality from Profile Measurements of Pavement Roughness
Authors: Janoff MS 
Published: March 2009

This paper summarizes the results obtained in five different states when profiles were used to develop transforms that predict rideability from pavement roughness. The five individual state transforms are very similar and have similar accuracy and validity. As a result, one transform—derived from the combined data from all five states—can be used to accurately predict rideability from profile measures of roughness in any of the five states.
The resulting transform is applicable to bituminous, Portland cement, and composite surfaces and the three types combined, and to both interstate and other classes of road. Use of this transform provides an efficient and accurate method for determining the rideability of pavement surfaces from physical measures of pavement roughness. This transform provides a basis for a system of measuring and reporting totally comparable roughness and rideability data that can also be used to assist highway agencies to determine when existing pavements should be repaired and to evaluate newly constructed pavements.
High-Performance Measurements for Programming and Controlling Maintenance of Surface Characteristics: Operational Systems in Use on Italian Motorways
Authors: Camomilla G , Malgarini M , Peroni G 
Published: March 2009

Maintaining pavement skid resistance depends on the geometric conditions of the road (straights, curves, slopes, etc.), weather conditions (wet or dry surfaces, etc.), and vehicle conditions (condition of brakes, tires, etc.). This paper reports the criteria adopted in establishing the more probable limit values associated with the various characteristics in question which are necessary to maintain safety without sacrificing economic management criteria.
Skid-resistance measurements, together with riding comfort index values, thus serve two main purposes: (1) In construction or maintenance of pavements, they serve as a means of quality control; pavements are deemed to have been laid properly only if certain characteristics correspond to pre-established acceptance requirements, and (2) During normal operations, they serve to pinpoint zones which require special intervention to restore skid resistance and smoothness, also taking into account in critical areas the problems of noise, which are gaining increasing attention here in Europe. These requirements have been spelled out in the technical tender specifications adopted for the IRI-ITALSTAT motorway network and include fines in cases of failure to respect these standards. In like manner, quality-control tests have been developed to assess the trend of skid resistance over time in composite materials taken from actual road pavements (passing the APA tests (Accelerated Polishing of Aggregates Using the British Wheel), which measure just the component materials).
The methodology already presented and proposed for the Italian motorway network, based on high-speed monitoring equipment such as the ARAN III, the longitudinal profile analyzer (APL), and the SUMMS (Survey Machine for Macrotexture and Skid, derived from the SCRIM), should ensure lasting, safe, and comfortable pavements obtained at optimal costs.
Errors in Automated Pavement Surface Distress Data Collection
Authors: Humplick F , McNeil S 
Published: March 2009

The massive condition inventory for highway systems requires continual inspection of pavement surface condition to evaluate pavement performance and make management related decisions. Typically, this requires intensive data collection in short periods of time, to make long-term predictions. Automated imaging techniques have been developed to obtain visual data quickly and efficiently. The automation process creates large amounts of data, most of which are removed during processing to highlight features of interest.
The pavement management process uses the results of measurement from these automated techniques for prediction and decision making. This process is very much affected by the accuracy of the measurements and the continual loss of accuracy at each processing stage. This loss of accuracy, in the most part, has been ignored in existing management systems.
This paper describes and illustrates error estimation techniques for automated data collection processes that model errors in the imaging system, data processing, and subjective input to processing. These accuracy estimation techniques can be used to assess the quantity of data needed, the appropriate quality of data, and the frequency of data collection. Finally, this analysis can be incorporated into the pavement management process as an error diagnostic system to aid in estimation and prediction of pavement performance, maintenance and rehabilitation expenditures, and to recommend or select data collection technologies.
Measurements and Criteria: Essential Elements for Pavement Management
Authors: Jordens R , de Wit B 
Published: March 2009

A systematic approach has been developed for planning the long-term maintenance of flexible pavements. This has resulted in a multi-year planning system which not only provides information about the type of maintenance required, but also details the cost and timing involved. Visual inspections are carried out to characterize the condition of the roads, coupled with rut depth and longitudinal evenness measurements. By comparison of the results of such tests with predefined guidelines, maintenance activities can be planned in a systematic way.
The choice of representative parameters to characterize the quality of the road network is outlined in this paper, as is the philosophy regarding maintenance guidelines. Furthermore, the measuring and inspection techniques employed are reviewed and the effects of possible errors discussed. Finally, recommendations are made as to how the system can be improved. The introduction of an automated data-collection system for surface distresses is seen as having the highest priority.
Impact of Roughness-Induced Dynamic Load on Flexible Pavement Performance
Authors: Papagiannakis AT , Haas RCG , Woodrooffe JHF , Leblanc PA 
Published: March 2009

This study deals with the impact of roughness-induced dynamic load on flexible pavement distress and performance. It involves field measurements of dynamic axle loads using the instrumented vehicle developed by the National Research Council in the context of the Road and Transportation Association of Canada Weights and Dimensions Study. Pavement distress and performance are modeled using a modified version of the Federal Highway Administration's (FHWA) VESYS-III-A model.
Measured standard deviations of dynamic load ranged from 8 to 42 kN, depending on vehicle speed, pavement roughness, and suspension type where the corresponding static load values were approximately 205 kN. It was concluded that for vehicle speeds higher than 40 km/h, the rubber suspension yields dynamic loads substantially higher than the air suspension. Furthermore, dynamic load waveforms from replicate runs were found repetitive in space. Although this loading condition is clearly not the case for pavements under in-service traffic, it was typical of the loading experienced by American Association of State Highway Officials (AASHO) Road Test sections. As a result, the latter is considered poorly randomized with respect to the impact of dynamic load.
A method is described for modeling the impact of the repetitive in space dynamic load experienced by a number of AASHO Road Test sections. Ten sections were analyzed, six of which developed severe roughness through their service lives. The methodology improved considerably the accuracy of performance predictions for four out of the six rough sections analyzed. Another part of the study examined the impact of suspension type on pavement performance assuming random application of dynamic loads. Performance predictions for the two suspensions were compared on the basis of the relative areas under the performance curves. With respect to the static load, the rubber suspension caused 17 and 22% additional damage for terminal serviceability values of 2.0 and 2.5, respectively. The corresponding values for the air suspension were 6 and 8%, respectively.
Road Macro- and Megatexture Influence on Fuel Consumption
Authors: Sandberg USI 
Published: March 2009

An experiment was conducted in which a specially instrumented Volvo 242 car was run at 50, 60, and 70 km/h over 20 road surfaces with various textures. Macro- and megatexture as well as the shorter wavelengths of unevenness were measured by a mobile laser profilometer, the signal of which was analyzed to obtain the texture profile spectrum for each surface in the 2- to 3500-mm texture wavelength range.
The fuel-consumption data at each speed and averaged for the three speeds were regressed on the texture profile spectrum data. The results show (1) Fuel consumption varies over a range of approximately 11% from the smoothest to the roughest road tested if texture wavelengths in the range 0.6 to 3.5 m are considered, and approximately 7% if texture wavelengths in the range 2 to 50 mm (macrotexture) are considered. (2) The correlation between fuel consumption and texture is as high as 0.90 (correlation coefficient) in the range 0.6 to 3.5 m and reduces smoothly at shorter wavelengths, down to about 0.60 at wavelengths equal to common maximum chipping sizes on roads. Thus it appears that fuel consumption is influenced very much by road unevenness and megatexture, but somewhat less by macrotexture. (3) Some of the mega- and macrotexture influence is due to a covariation with shortwave unevenness, and the pure effects of each, especially macrotexture, are somewhat less than noted in (1) and (2). (4) The results indicate that significant parts of the losses may occur at frequencies typical of vehicle body and wheel hop resonances and, thus, be dissipated in the car suspension system. (5) The results demonstrate that the road surface quality has a great impact on car fuel consumption, and that the largest potential for improvements may be to control megatexture and, most of all, shortwave unevenness on roads. Also macrotexture is important to control, at least when car speeds of 60 to 70 km/h are common. The unevenness at longer wavelengths has not been covered in this experiment.
Analysis and Evaluation of the Performance of Porous Asphalt: The Spanish Experience
Authors: Pérez Jiménez FE , Calzada Pérez MA 
Published: March 2009

The excellent qualities of pervious wearing courses which enhance road safety and comfort are well known. However, there are very few test and control methods which allow these courses to be planned and used adequately. The design of the porous asphalts used in the construction of these pervious wearing courses depends on a number of rules of thumb derived from their use, but there is no test method or procedure which might allow their properties to be characterized and optimized.
In this paper, we describe the procedure and planning criteria which are used in Spain in the design of porous mixes and which were established both from the behavior of these mixes in use and from the results of tests performed in the laboratory. The procedure used is based on optimizing two fundamental characteristics of these mixes: permeability and resistance to disintegration. We have developed two testing methods which allow both properties to be assessed. Permeability is assessed in situ by means of the Laboratorió de Caminos de Santander (LCS) permeameter and resistance to disintegration is evaluated by means of the Cantabrian abrasion loss test. These two tests optimize the design of these mixes and allow the effect on their behavior of using modified binders to be evaluated. We also describe the effects that these mixes have on adhesion, texture, and noise of the wearing course surface compared with other materials used in road surfacing.
Methods for Sampling Fluids in the Vadose Zone
Authors: Wilson LG 
Published: March 2009

This paper reviews available methods for sampling water-borne pollutants in the vadose zone. The “standard” method for sampling pore fluids in the vadose zone is core sampling of vadose zone solids, followed by extraction of pore fluids. The preferred method for solids sampling is the hollow-stem auger with core samplers. Core sampling does not lend itself to sampling the same location time and again. Membrane filter samplers and porous suction samplers are an alternative approach for sampling fluids in both saturated and unsaturated regions of the vadose zone. There are three basic porous suction sampler designs: (1) vacuum-operated suction samplers, (2) pressure-vacuum lysimeters, and (3) high-pressurevacuum samplers.
Suction samplers are constructed mainly of ceramic and polytetrafluoroethylene (PTFE). The effective range of ceramic cups is 0 to 60 cbar of suction. The operating range of PTFE cups installed with silica flour is 0 to 7 cbar of suction. This paper reviews a method for extending the sampling range of suction samplers using an injection-recovery procedure. Factors affecting the operation of porous suction samplers include the physical properties of the vadose zone, hydraulic conditions, cup-wastewater interactions, and climatic conditions. Innovative procedures include the water extractor and the filter-tip system sampler. The free-drainage samplers include pans, blocks, and wick-type samplers. Techniques for sampling from perched ground-water zones include profile samplers, sampling from cascading wells, and sampling from dedicated wells.
Tensiometers—Theory, Construction, and Use
Authors: Stannard DI 
Published: March 2009

Standard tensiometers are used to measure matric potential as low as -870 cm of water in the unsaturated zone by creating a saturated hydraulic link between the soil water and a pressure sensor. The direction and, in some cases, quantity of water flux can be determined using multiple installations.
A variety of commercial and fabricated tensiometers are commonly used. Saturated porous ceramic materials, which form an interface between the soil water and the bulk water inside the instrument, are available in many shapes, sizes, and pore diameters. A gage, manometer, or electronic pressure transducer is connected to the porous material with small- or large-diameter tubing. Selection of these components allows the user to optimize one or more characteristics, such as accuracy, versatility, response time, durability, maintenance, extent of data collection, and cost.
Special designs have extended the normal capabilities of tensiometers, allowing measurement in cold or remote areas, measurement of matric potential as low as -153 m of water (-15 bars), measurement at depths as deep as 6 m (recorded at land surface), and automatic measurement using as many as 22 tensiometers connected to a single pressure transducer.
Continuous hydraulic connection between the porous material and soil, and minimal disturbance of the natural infiltration pattern are necessary for successful installation. Avoidance of errors caused by air invasion, nonequilibrium of the instrument, or pressure-sensor inaccuracy will produce reliable values of matric potential, a first step in characterizing unsaturated flow.
Experimental Screen Design for More Sediment-Free Sampling
Authors: Rich CA , Beck BM 
Published: March 2009

An experimental double-walled screen design has been found to increase the reliability of a properly installed, monitoring well sand pack, intended to produce long-term sediment-free sampling. The screen design is most useful for shallow, small-diameter monitoring wells installed by the hollow-stem auger drilling method and can be produced in a wide range of lengths and diameters. The new screen design eliminates the need for state agencies to require “tremied” gravel packs for such wells when the tremie-pipe installation technique is difficult to complete successfully without compromising the intent behind the specification. The double-walled screen design contains an economically fabricated, preassembled, evenly graded sand pack that avoids the need for resin and that ensures emplacement of an in situ homogeneous sand pack in the field.
When installed directly against the formation wall, in conjunction with a conventional sand pack or the best efforts at a tremied pack, the preassembled double-walled screen and sand pack may help reduce the amount of development time necessary to obtain turbidity-free water (that is, water containing less than 50 nephelometric turbidity units). The presence of the preassembled homogeneous sand pack downhole improves long-term sample integrity in silty deposits and minimizes interference attributable to improperly placed or poorly settled packs. The sand pack example described is simple in design and economical, accommodates small-diameter submersible pumps and bailers, and is easily fabricated in the field.
Monitoring Well Development—Why and How
Authors: Kill DL 
Published: March 2009

The objectives of monitoring well development are these: (a) to permit taking of sediment-free samples, (b) to allow water to flow freely into the well so representative samples can be taken rapidly, and (c) to remove all traces of the drilling fluid used in order to minimize any interference with the water quality.
Several development methods have been well documented as to their practicality and effectiveness in developing water supply wells. These methods are mechanical surging, overpumping, air lift, high-velocity water jetting, and several combinations of these methods. All of these methods can be used in monitoring well development but have limitations. Their limitations are usually related to the well diameter, restrictions on placing foreign materials in the well, low-permeability formations, and poor well intake design.
The methods and limitations are reviewed in this paper.
Monitoring Wells: Maintenance, Rehabilitation, and Abandonment
Authors: Winegardner DL 
Published: March 2009

This paper presents an overview of the technical considerations and field procedures involved in monitoring well maintenance, rehabilitation, and abandonment. It includes criteria that should be considered throughout the life span of the well to ensure that the well serves its purpose optimally and that, when removed from service, it is no threat to the environment. The primary purpose of this paper is to provide guidance in selecting the most acceptable field procedures.
Even though monitoring wells are intended to be sources of reliable data, each well introduces a number of limited control variables that may affect the reliability of the analytical data. Regular maintenance of monitoring wells, both structurally and hydrologically, is required to preserve optimal performance of the well. Well maintenance principles are discussed in this paper, and recommendations for procedures are provided.
Major changes to a well may be required when it no longer serves its original purpose. The benefits of rehabilitation procedures are discussed and related to the risk of accepting changes in the established data base.
Abandonment (or decommissioning) of monitoring wells is necessary when they no longer serve their intended purpose. At that time, the well must be brought to a neutral condition which is compatible with the soil matrix, ground-water quality, and the chemicals monitored and which also preserves the hydrogeological integrity of the specific location. Examples of successful closures are presented to illustrate these general principles.
Sorption of Aromatic Hydrocarbons by Materials Used in Construction of Ground-Water Sampling Wells
Authors: Gillham RW , O'Hannesin SF 
Published: March 2009

Sorption of dissolved constituents from water within a sampling well onto well-casing materials or sampling equipment is frequently cited as a potential source of bias in ground-water sampling programs. This study examined the sorption of six monoaromatic hydrocarbons (benzene, toluene, ethylbenzene, and m-, o-, and p-xylene) onto seven sampling well materials. The materials included stainless steel, rigid polyvinyl chloride (PVC), polytetrafluoroethylene (PTFE), polyvinylidene fluoride, epoxy-impregnated fiberglass, flexible polyvinyl chloride (PVC), and polyethylene. Samples of the test materials were exposed to aqueous solutions containing the six organic compounds for time periods ranging from 5 min to 8 weeks. The concentration remaining in solution, at the end of the exposure period relative to the initial concentration, was taken as a measure of the degree of sorption.
No uptake of any compound onto stainless steel was noted, while some degree of sorption was observed for all compounds on all polymer well-casing materials. Sorption increased with increasing hydrophobicity of the organic compounds. The sorption increased in this order: benzene, toluene, o-xylene, m-xylene, ethylbenzene, and p-xylene. Of the polymer materials, rigid PVC showed the least sorption, followed by fiberglass and polyvinylidene fluoride (which were similar) and PTFE. The flexible tubing, polyethylene, and flexible PVC showed the highest rates of uptake, with significant losses from solution by the first sampling time (5 min).
The experimental data were shown to follow a diffusion model closely, with effective diffusion coefficients corresponding to different rates of uptake from solution. The model was used to extend the experimental results to monitoring wells of different diameter.
Stainless steel and PTFE are commonly recommended as preferred materials for constructing monitoring wells, particularly if organic contamination is expected. Under the conditions of this study, and based only on their relative sorption characteristics, several polymer materials, including rigid PVC, are as advantageous and possibly more advantageous than PTFE.
Methods for Evaluating Short-Term Fluctuations in Ground Water Levels
Authors: Sayko SP , Ekstrom KL , Schuller RM 
Published: March 2009

During several investigations of ground water contamination, relatively large fluctuations in ground water levels—which occurred in a time interval shorter than that necessary to collect a round of water levels—were observed. However, because of their short-term nature, it was not possible to collect the data necessary to characterize fully the effects of these fluctuations when using standard water level measurement techniques. Without such a characterization, these short-term fluctuations in ground water levels can seriously impair interpretation of the ground water flow system.
In a case history presented, tidal and other environmental influences were large enough to make a normal round of water level data useless in interpreting ground water flow. Monitoring of water levels at the site for a period of eight days, using electronic water level recording instruments, allowed evaluation of the fluctuations and determination of an acceptable method of collecting site water levels. To evaluate ground water levels properly, multiple rounds of water levels had to be collected and averaged to filter the noise, or short-term fluctuations, from the water level data. Monitoring for these short-term fluctuations in ground water levels should be considered good engineering practice in any ground water investigation.