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    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Directional evolution characteristics of asphalt pavement texture indicators and skid resistance performance under simulated accelerated polishing</title>
      <link>https://trid.trb.org/View/2635542</link>
      <description><![CDATA[Conventional pavement surface texture and skid resistance evaluation methods neglect directional variations arising from polishing under one-way traffic flow. This study enhances understanding of directional texture evolution and its impact on skid resistance. Six asphalt mixtures underwent accelerated unidirectional polishing. Directional texture indicators and power spectral density (PSD) were extracted using a prominence-based algorithm. Directional skid resistance was quantified via British Pendulum Tests performed in forward and backward directions. The results indicate that traffic polishing induces roughness decay 3.2–6.5 % faster in the backward direction than in the forward direction during early stages. PSD analysis confirmed that polishing affects micro-texture more significantly than macro-texture, with consistently lower backward PSD values. Skid resistance deterioration exhibited directional patterns strongly correlating with texture evolution (Pearson’s r = 0.73–0.85), particularly under wet conditions. This work establishes directional texture polishing as the fundamental mechanism underlying directional skid resistance differences, enabling the development of driving-pattern-based multi-directional evaluation systems.]]></description>
      <pubDate>Thu, 02 Apr 2026 16:58:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2635542</guid>
    </item>
    <item>
      <title>Feasibility of handheld X-ray fluorescence analyser for predicting aggregate frictional resistance using elemental composition</title>
      <link>https://trid.trb.org/View/2598415</link>
      <description><![CDATA[Since about 95% by mass of hot mix asphalt mixes comprise mineral aggregates, the frictional properties of the mixes are, for the most part, dictated by the frictional properties of the aggregates. A popular way of assessing the aggregates’ frictional performance has been using the three-wheel polishing device (TWPD) to simulate the long-term polishing and the dynamic friction tester (DFT) to measure the friction. One of the concerns of the transportation agencies with this process is the length of time needed to complete these tests on one aggregate source. This study examined the feasibility of using aggregate elemental composition using a portable X-ray fluorescence analyser (PXRF) for the rapid assessment of the frictional resistance of aggregates. Based on testing twenty-six diverse aggregate sources, the frictional resistance of aggregates as polished with the TWPD and tested with the DFT could be estimated well from their elemental composition.]]></description>
      <pubDate>Mon, 24 Nov 2025 15:30:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/2598415</guid>
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    <item>
      <title>Applicability of Gneiss Based Mineral Aggregates for the Use in High Friction Surface Treatment in Terms of Polishing Characteristics</title>
      <link>https://trid.trb.org/View/2408017</link>
      <description><![CDATA[Speed and safety management of highways plays a prominent role in ensuring road user safety, especially of the vulnerable categories. Pavement Friction Management (PFM) is being considered as the best possible option in developing the road infrastructure over the other prevalent strategies, with the focus of improving user safety. High Friction Surface Treatment (HFST) is widely being used as a remedial measure to improve the friction and texture retention capacity of the wearing course, as it provides economical and sustainable solutions in upgrading the pavement performance in both as an urgent response and in the long run as well. As an urgent remedial intervention, HFST can be incorporated in the national practice of safety management in Sri Lanka, to address the concerns over the escalating numbers of grievous highway crashes. In place of the most commonly used high skid resistant aggregates, gneiss-based mineral aggregate can be a viable alternative since it delivers similar functionality to that of granites. The study examines the polishing characteristics of widely used gneiss-based roadstones in the country through laboratory experiments involving the Polish Stone Value (PSV) test. Both qualitative and quantitative analyses of the specified physical and mechanical laboratory testing are conducted to evaluate the applicability of gneiss-based mineral aggregates in the use of HFST as an alternative skid-resistant roadstone in terms of their polishing behavior.]]></description>
      <pubDate>Wed, 24 Sep 2025 15:24:34 GMT</pubDate>
      <guid>https://trid.trb.org/View/2408017</guid>
    </item>
    <item>
      <title>An Assessment of the Polishing Behaviour of Road Surfacing Aggregates in Sri Lanka</title>
      <link>https://trid.trb.org/View/2408004</link>
      <description><![CDATA[Friction capacity between the tire-pavement interface, facilitates sufficient braking force ensuring road user safety. Inadequate skid resistance has been identified as the prominent pavement-related cause of highway crashes. Availability of friction at the wearing course is governed by pavement, vehicle and tire/driver condition parameters combined with environmental parameters, of which pavement-related characteristics concern a greater proportion. Crucial pavement-related characteristics include mineralogical and textural properties of road surfacing aggregates, where the polishing behaviour of coarse aggregates exhibits significant influence in the establishment of skid resistance of asphalt concrete pavings. Thus, many research have been conducted to determine the suitability of aggregates, in terms of resistance to polishing under trafficking. In the national context, broader attention is being developed towards road safety as one of the critical performance parameters due to the integration of an expressway system with the prevailing road network. However, the amount of such extensive study into pavement friction and properties of locally available aggregates, is scarce. No guidelines considering user safety have been specified in the Standard Specifications for Construction and Maintenance of Roads and Bridges by the Institute for Construction Training and Development, Sri Lanka. Therefore, initiatives to incorporate skid resistance in the national practice of aggregate selection for pavement construction, are indispensable. Hence, this study aims to establish the friction characteristics of Sri Lankan natural roadstones, through the Polish Stone Value Test involving the Accelerated Polishing Machine and the British Pendulum Tester, and to evaluate the observed polishing patterns through a petrographic analysis and microscopic investigation.]]></description>
      <pubDate>Wed, 24 Sep 2025 08:57:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/2408004</guid>
    </item>
    <item>
      <title>Characterization of Aggregate Susceptibility to Polishing Using the Micro-Deval Test</title>
      <link>https://trid.trb.org/View/2598679</link>
      <description><![CDATA[Skid resistance is a critical pavement surface property affecting roadway safety, especially under wet weather conditions. This study evaluated the frictional characteristics of a wide variety of aggregates used in roadway construction in Ohio. The micro-Deval test was used to apply different levels of polishing (0, 60, 180, and 360?min) to each aggregate material, and the frictional properties of the unpolished and polished aggregates were evaluated using a British pendulum tester (BPT) and a dynamic friction tester (DFT). Texture and angularity of the unpolished and polished aggregates were also evaluated using the second-generation Aggregate Image Measurement System (AIMS2). Carbonate aggregates were generally found to exhibit higher initial friction than natural gravels, but some carbonate aggregates provided poor friction retention after polishing. Slag aggregates were found to have high initial friction properties and good friction retention, while the trap rock used in this study exhibited relatively low initial friction and poor friction retention. It was found in this study that mass loss after abrasion in the micro-Deval test is not a good indicator of the aggregate’s resistance to polishing. Some aggregates exhibited high mass loss but maintained high friction properties, while others showed low mass loss and poor friction retention. The AIMS2 texture was also found to have a relatively low correlation with direct contact friction measurements obtained using the BPT and the DFT. These findings confirm the need for direct contact friction measurements to properly characterize aggregate susceptibility to polishing.]]></description>
      <pubDate>Sat, 13 Sep 2025 17:46:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2598679</guid>
    </item>
    <item>
      <title>Correlation of Laboratory Three-Wheel Polisher Revolutions with Roadway Accumulated-Traffic to Evaluate Laboratory Polishing of Pavements</title>
      <link>https://trid.trb.org/View/2593938</link>
      <description><![CDATA[Prior to conducting laboratory dynamic friction tests (DFTs), a three-wheel polisher is used to simulate the polishing effect of traffic on asphalt pavements. Limited research has looked at how the number of revolutions completed by a three-wheel polisher correlates with real-world cumulative traffic volume. Establishing correlations between the number of three-wheel polisher revolutions and real-world traffic volume will clarify how aggregate polishing affects pavement friction.]]></description>
      <pubDate>Thu, 28 Aug 2025 11:32:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2593938</guid>
    </item>
    <item>
      <title>Assessment of Laboratory Friction Testing Equipment and Validation of Pavement Friction Characteristics with Field and Accelerated Friction Testing</title>
      <link>https://trid.trb.org/View/2536109</link>
      <description><![CDATA[This report reviews the research and advancements in using the Three-Wheel Polishing Device (TWPD) for aggregate polishing and the Dynamic Friction Tester (DFT) to measure the polishing resistance of coarse aggregates in asphalt wearing course mixes. The Louisiana Department of Transportation and Development (DOTD) currently employs the British Polishing Wheel (BPW) test procedure to determine the polished stone value (PSV) of aggregates and specifies PSV-based aggregate friction rating requirements in asphalt mixture design for wearing courses. However, due to significant variations in aggregate production and shipments, it is common for the same type of aggregate, delivered at different times, to yield substantially different PSV results. In this project, seven coarse aggregate sources, including three sandstone types, three limestone types, and one rhyolite type, were selected, and eight field pavement sections were identified for laboratory and field friction testing. The primary objectives were: (1) to assess variations of PSV test results; (2) to evaluate a new TWPD-based aggregate friction testing procedure; (3) to validate and update the previously developed harmonization correlations for different field friction measurements; and (4) to determine threshold friction design values (i.e., DFT and mean profile/texture depth values) for commonly used wearing course mixtures in Louisiana.]]></description>
      <pubDate>Mon, 21 Apr 2025 12:03:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/2536109</guid>
    </item>
    <item>
      <title>Polishing-induced skid resistance deterioration characteristics of grooved runway pavements</title>
      <link>https://trid.trb.org/View/2519030</link>
      <description><![CDATA[The effect of polishing on the skid resistance performance of grooved pavement surfaces has not been adequately addressed by researchers. This research conducted a laboratory polishing study to compare the skid resistance deterioration characteristics of ungrooved surfaces and grooved surfaces having the standard 6 x 6 x 38 mm (width x depth x center-to-center spacing) grooves. It was found that grooved surfaces received more severe polishing than ungrooved surfaces, and the initial skid resistance advantage of a grooved surface could be significantly reduced due to polishing during service. The findings suggest that even though the presence of grooves help to relieve hydrodynamic pressure when an aircraft moves on a wet grooved runway pavement at high speeds, the advantage of reducing hydroplaning and skidding risks would become less as the pavement’s service period increases. Therefore, the overall benefits of grooved pavements should be assessed at its polished state.]]></description>
      <pubDate>Thu, 27 Mar 2025 11:37:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/2519030</guid>
    </item>
    <item>
      <title>Numerical determination of pavement mean texture depths at different degrees of traffic polishing-induced wear</title>
      <link>https://trid.trb.org/View/2509312</link>
      <description><![CDATA[All existing digital image-based numerical mean texture depth (MTD) calculation methods are unable to achieve a consistent level of acceptable accuracy for MTD values calculated at different degrees of pavement polishing. To solve this problem, a novel procedure is proposed to determine MTD as a function of degree of polishing represented by a texture statistic ‘directional wear index’ DWI. First, a relationship is established between DWI and the elevation 𝘏eq that defines the equivalent top surface of MTD. 𝘏eq is derived from 3-D digital image based on the concept of planation surface. Through studying laboratory specimens and field pavements polished to different degrees, a well-defined relationship between DWI and 𝘏eq was established. Knowing Heq from the 𝘏eq–DWI relationship, MTD is calculated as the mean depth of the voids between 𝘏eq and the test surface. The digital image-based procedure is able to concurrently determine MTD and the surface's degree of polishing.]]></description>
      <pubDate>Thu, 27 Feb 2025 10:46:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/2509312</guid>
    </item>
    <item>
      <title>Research on the evolution law of aggregate micro-texture during long-term wearing of asphalt pavement</title>
      <link>https://trid.trb.org/View/2418510</link>
      <description><![CDATA[The micro-texture of aggregates plays a very important role in anti-skid performance of asphalt pavement. Three kinds of aggregates, limestone, basalt and sandstone, were used to prepare asphalt mixture to study the evolution law of micro-texture of aggregates under long-term wear. One Third Scaled Model Mobile Load Simulator (MMLS) was used to conduct wear tests on asphalt mixtures under two working conditions: drying and water immersion. Laser confocal scanning microscopy (LCSM) was used to test and analyze the micro-texture evolution of the original aggregate, mixed aggregate, and accelerated loaded aggregate surfaces. The mechanism of texture evolution was analyzed based on the mineral composition, Vickers hardness, and micro-structure of the aggregate. The results show that wear can lead to varying degrees of polishing of the aggregate micro-texture, with limestone>basalt>sandstone, and the drying condition is more severe than the water immersion condition. The wear degree of the texture is closely related to the mineral composition and hardness of the aggregate. The more complex the mineral composition, the greater the hardness and hardness dispersion, the less likely the texture will be polished. The micro-texture indexes Ra and Rq have the highest correlation with anti-skid performance, and the relationship between them is obtained by fitting. Scanning electron microscopy (SEM) shows that the fine particles in sandstone are easy to fall off, which is conducive to the regeneration of texture, and is also the internal reason for its best anti-skid durability.]]></description>
      <pubDate>Tue, 10 Sep 2024 17:03:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2418510</guid>
    </item>
    <item>
      <title>Establishing Polishing Values of Aggregates for Use in Surface Asphalt Mixtures – Laboratory Evaluation</title>
      <link>https://trid.trb.org/View/2387402</link>
      <description><![CDATA[Ensuring the safety and functionality of Virginia's road and bridge infrastructure is a paramount responsibility of the Virginia Department of Transportation (VDOT). VDOT's specifications place significant emphasis on utilizing non-polishing aggregates in surface asphalt layers to ensure acceptable levels of friction (skid resistance) for the safety of the traveling public. Section 200.04 of VDOT’s Road and Bridge Specifications defines non-polishing aggregate as material capable of delivering acceptable skid resistance when exposed in roadway or bridge deck wearing surfaces. However, it is important to note that the department retains the authority to evaluate and decide whether proposed aggregates meet the standards for polishing characteristics. This indicates a potential gap in the existing guidelines or specifications regarding non-polishing requirements, as the specifications do not provide clear criteria in this regard.

A specific concern arises from the classification of carbonate aggregates, such as limestone and dolomite, as "polishing" based on their mineralogical composition. This categorization imposes restrictions on the use of these aggregates in most asphalt pavement surfaces, particularly in the western region of Virginia where carbonate rocks are the predominant source materials. Consequently, the transportation of non-polishing aggregates over considerable distances becomes necessary, leading to a substantial increase in construction costs and subsequent maintenance and rehabilitation expenditures, and associated environmental burdens.

The objective of this research study is to develop a criterion for evaluating the polishing characteristics of aggregates used in surface asphalt mixtures within a laboratory setting. 
]]></description>
      <pubDate>Thu, 06 Jun 2024 08:48:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/2387402</guid>
    </item>
    <item>
      <title>Influence of Aggregate Mineral Grain Size and Size Distribution on Pavement Surface Microtexture Deterioration</title>
      <link>https://trid.trb.org/View/2359144</link>
      <description><![CDATA[The objective of this paper is to assess the impact of mineral grain size and grain size distribution of aggregates on the deterioration of pavement surface microtexture. For the study, aggregates were collected from nine different sources to cover a wide variation in mineralogical type. The grain size parameters were obtained by detecting mineral grain boundaries using scanning electron microscope electron back scattered diffraction (SEM EBSD) analysis on thin sections prepared from the aggregates. Scanning electron microscope (SEM) analysis was also carried out on thin sections of all aggregate types to determine their mineralogical composition. Microtexture deterioration was measured by collecting the British pendulum number (BPN) of the aggregate after every hour of polishing for six hours using an accelerated polishing machine. From the mineral composition analysis, it was observed that the aggregates in the study belonged to three rock types: granite, amphibolite, and basalt (three sources of each type). The BPN values of the polished stones indicated that aggregates with finer grains offer more resistance to polishing. Statistical analysis of the test results also suggests that a wide variation in grain sizes in aggregates positively contributes to resistance against polishing. The study confirmed that, for a given rock type, coarse aggregates with finer grains and greater variation in grain size can better withstand microtexture deterioration caused by mechanical polishing from vehicular loads when used in the surface course of pavements.]]></description>
      <pubDate>Fri, 10 May 2024 16:50:59 GMT</pubDate>
      <guid>https://trid.trb.org/View/2359144</guid>
    </item>
    <item>
      <title>Multiscale analyse of the relation between skid resistance and pavements surfaces texture evolution with polishing</title>
      <link>https://trid.trb.org/View/2321760</link>
      <description><![CDATA[It is known from the literature that skid resistance is closely related to road surface roughness. This paper aims to develop a multiscale texture decomposition method able to identify the relevant scales that affect pavement surfaces’ skid resistance variation during polishing. This method is based on continuous wavelets decomposition and. It is applied on seven pavement surfaces before and after polishing. The polishing is done in the laboratory using the Wehner & Schulze apparatus, which also serves for skid esistance measurements. At each step of polishing, 3D topographical maps of the test surface are realised with an optical sensor. On these maps, multiscale texture parameters are calculated after the multiscale decomposition. Analysis of these parameters shows their ability to represent the increase and the rate of increase in skid resistance in early age (increase in multiscale parameters for scale range 300–3000 µm) of pavement surfaces and the long-time skid resistance decrease (decrease in multiscale parameters for scale range 0–1000 µm.]]></description>
      <pubDate>Tue, 30 Jan 2024 09:25:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2321760</guid>
    </item>
    <item>
      <title>Directional skid resistance assessment of horizontal-curve pavements</title>
      <link>https://trid.trb.org/View/2167170</link>
      <description><![CDATA[This research demonstrated through a field study that directional polishing effects of cornering traffic produced significant differential directional skid resistance. The pattern of differential directional skid resistance varied along a horizontal curve. In the front straight segment, the most severe polishing occurred in the traffic direction, while in the rear straight segment the most severe polishing was in the backward against-traffic direction. In the curve segment, the centrifugal forces generated from the cornering movements of vehicles caused the most significant polishing in the radial outward direction. Combined polishing effects in both the lateral and longitudinal directions were found in the front and rear transition segments. The test results showed that the current pavement design practice of considering skid resistance in the forward direction is unsatisfactory as it would over-estimate pavement resistance to skidding in the radial direction.]]></description>
      <pubDate>Mon, 16 Oct 2023 17:09:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/2167170</guid>
    </item>
    <item>
      <title>Effect of Blending Steel Slag Aggregates on the Polishing Resistance of Asphalt Pavement Surface</title>
      <link>https://trid.trb.org/View/2125982</link>
      <description><![CDATA[The objective of the work presented in this paper is to investigate the effect of blending steel slag aggregates (SSAs) with natural aggregates (NAs) on the polishing resistance of the asphalt pavement surface. The investigation involved polishing five sources of NA (granite [3] and amphibolite [2]), one source of SSA, and three SSA blends (mass proportions: 20/80, 50/50 and 80/20). The polishing trends were captured by measuring the British Pendulum Number (BPN) at hourly intervals for 9 h. The laboratory polishing trends suggested that the SSA blending resulted in improved polishing resistance. Based on the polishing trends observed in the laboratory, a suitable mathematical form was selected to model the aggregate polishing. The transfer functions (or shift factors) for the field model were derived by comparing the laboratory polishing with the field polishing trends. The field polishing trend was captured by BPN collected over 3 years at selected locations on two pavements with stone matrix asphalt (SMA) surfaces course mix that were produced with the same aggregates tested in the laboratory. The prediction results from the field BPN deterioration models showed good consistency between field observations and model response values. Using the derived shift factors and laboratory BPN deterioration model parameters, field models for BPN deterioration were developed based on which life prediction of pavement with SMA surface can be made. Field BPN deterioration models suggest that blending of SSA prolongs the residual life up to 10 % depending on the blend proportion and threshold BPN criteria.]]></description>
      <pubDate>Mon, 24 Apr 2023 16:19:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/2125982</guid>
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