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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <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>
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      <title>Transport Research International Documentation (TRID)</title>
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      <title>Thermally Conductive Pre-cast Concrete Pavement for Urban Heat Island Mitigation</title>
      <link>https://trid.trb.org/View/2673590</link>
      <description><![CDATA[Urban areas experience elevated pavement temperatures due to the urban heat island (UHI) effect, which increases cooling energy demand and associated carbon emissions. In this project, the work focused on three main components: (1) a comprehensive mechanical study of precast concrete mixes containing microencapsulated organic phase change material (PCM), (2) three-dimensional transient thermal finite element (FE) simulations, and (3) full-scale sidewalk testing evaluated using a Monthly Cooling Benefit Index (MCBI). The mechanical program quantified the influence of PCM dosage on workability and compressive strength and showed a clear trend of decreasing strength with increasing PCM content. However, mixes with moderate PCM dosages retained adequate strength for sidewalk applications, while still providing measurable cooling potential. The calibrated 3D FE model captured the main experimental trends by representing PCM as an increase in effective heat capacity and a reduction in thermal diffusivity. Simulation results confirmed that PCM integration consistently reduced peak surface temperatures relative to the control slab, with mid-range PCM contents offering the best balance between thermal moderation and mechanical performance. A full-scale pilot sidewalk with multiple precast segments—combining PCM with different surface finishes such as sandblasting and diamond grinding—was constructed on the University of Texas at San Antonio campus and monitored over continuous three months. Field measurements showed that segments with moderate PCM content (e.g., around 2.5%) coupled with reflective/high-albedo surface treatments achieved the most persistent reductions in surface temperature compared with the conventional control and PCM-only panels. When quantified using the MCBI, the sandblasted and diamond-ground PCM segments ranked highest, indicating that the combined strategy of moderate PCM dosage and optimized surface finishing provides the most effective and practical cooling benefit for UHI mitigation in urban sidewalks.]]></description>
      <pubDate>Tue, 10 Mar 2026 09:54:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/2673590</guid>
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      <title>Thermally Conductive Pre-cast Concrete Pavement for Urban Heat Island Mitigation [supporting dataset]</title>
      <link>https://trid.trb.org/View/2673607</link>
      <description><![CDATA[Abstract of the final report is stated below for reference: Urban areas experience elevated pavement temperatures due to the urban heat island (UHI) effect, which increases cooling energy demand and associated carbon emissions. In this project, the work focused on three main components: (1) a comprehensive mechanical study of precast concrete mixes containing microencapsulated organic phase change material (PCM), (2) three-dimensional transient thermal finite element (FE) simulations, and (3) full-scale sidewalk testing evaluated using a Monthly Cooling Benefit Index (MCBI). The mechanical program quantified the influence of PCM dosage on workability and compressive strength and showed a clear trend of decreasing strength with increasing PCM content. However, mixes with moderate PCM dosages retained adequate strength for sidewalk applications, while still providing measurable cooling potential. The calibrated 3D FE model captured the main experimental trends by representing PCM as an increase in effective heat capacity and a reduction in thermal diffusivity. Simulation results confirmed that PCM integration consistently reduced peak surface temperatures relative to the control slab, with mid-range PCM contents offering the best balance between thermal moderation and mechanical performance. A full-scale pilot sidewalk with multiple precast segments—combining PCM with different surface finishes such as sandblasting and diamond grinding—was constructed on the University of Texas at San Antonio campus and monitored over continuous three months. Field measurements showed that segments with moderate PCM content (e.g., around 2.5%) coupled with reflective/high-albedo surface treatments achieved the most persistent reductions in surface temperature compared with the conventional control and PCM-only panels. When quantified using the MCBI, the sandblasted and diamond-ground PCM segments ranked highest, indicating that the combined strategy of moderate PCM dosage and optimized surface finishing provides the most effective and practical cooling benefit for UHI mitigation in urban sidewalks.]]></description>
      <pubDate>Tue, 10 Mar 2026 09:54:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/2673607</guid>
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    <item>
      <title>Evaluation and Correlation of the Dynamic Friction Tester on Iowa Pavement Surfaces</title>
      <link>https://trid.trb.org/View/2636168</link>
      <description><![CDATA[Frictional properties of pavement surface materials on roadway shoulders and highway ramps are of concern to state and county pavement engineers. Currently, the frictional properties of pavement surfaces are obtained via testing with a locked‐wheel skid trailer. Operational limitations prohibit the use of a locked‐wheel skid trailer on roadway shoulders and highway ramps. A Dynamic Friction Tester (DFT) can be used in these areas to test for frictional quality and characteristics of the pavement surface.]]></description>
      <pubDate>Mon, 02 Mar 2026 16:12:38 GMT</pubDate>
      <guid>https://trid.trb.org/View/2636168</guid>
    </item>
    <item>
      <title>Updated Methods for Identification of Road Surface Type Using Machine Learning-Enabled Remote Sensing</title>
      <link>https://trid.trb.org/View/2663611</link>
      <description><![CDATA[This article discusses how addressing and documenting challenges with the available State of Michigan aerial imagery enabled development of a machine-learning-based imagery analysis methodology that was able to assign road surface type to a statewide road network using a large set of high-resolution imagery. The methods were most accurate for the asphalt class, and for a general paved category when combining asphalt and concrete roads. Unpaved roads, and especially concrete, had lower accuracy, although the length-weighted F1 score of 89.9 percent means that roads are generally accurately identified with road surface type. The authors used the XGBoost model, training data, independent ground truth, a “roadness” concept, analysis of brightness values, supplementary data, and a review of detailed accuracy scores as the main methodology to accomplish the road surface identification for Michigan’s 83 counties. They anticipate that their methods are readily portable to other locations where similar imagery is available and training data can be obtained.]]></description>
      <pubDate>Wed, 25 Feb 2026 14:28:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/2663611</guid>
    </item>
    <item>
      <title>Assessment of Factors Influencing the Number and Consequences of Electric Scooter Accidents</title>
      <link>https://trid.trb.org/View/2643354</link>
      <description><![CDATA[Micromobility is gaining momentum in many countries, helping reduce congestion and pollution in the streets of major cities. The use of e-scooters has increased rapidly over the past three years, posing additional risks to road safety. Therefore, it is necessary to identify the key factors influencing the number of accidents and their consequences. The current article assesses eight e-scooter safety importance criteria, applying various methods and consulting highly qualified experts. It is noteworthy that the maximum weights of criteria determined by the ARTIW-L, ARTIW-N (Average Rank Transformation into Weight Linear and Non-Linear), and AHP (Analytic Hierarchy Process) methods are consistent. Evaluating the opinions of 15 experts using the ARTIW-L, ARTIW-N, DPW (Direct Percentage Weight), and AHP methods allowed for the determination of average criterion weights and the ranking of their priorities. Averaging the criteria weights calculated by the four expert evaluation methods yields the following overall priority order: Type and quality of road surface≻Road or street element≻Maximum power≻Speed limits≻Mandatory helmet use≻Seasonality≻Age of the road user≻Educational activities. The findings highlight that the type and quality of the road surface, as well as road or street design, have the greatest impact on e-scooter safety. These insights can guide urban planners and policymakers in prioritizing infrastructure improvements and developing evidence-based safety regulations for micromobility users.]]></description>
      <pubDate>Wed, 25 Feb 2026 09:05:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2643354</guid>
    </item>
    <item>
      <title>Research on Road Surface Feature Extraction Method Based on Mobile Phone Image</title>
      <link>https://trid.trb.org/View/2613043</link>
      <description><![CDATA[In this paper, a close-range photogrammetry method based on smart phone imaging platform is used to verify the applicability of smart phone photography in road texture modeling. Firstly, the image of asphalt pavement is collected by smart phone, and the proportion of the interest area of pavement texture features to the whole image is calculated by Adobe Photoshop and then grouped. Secondly, based on the principle of photogrammetry and a 3D model, based on the relevant functions of Reality Capture, the captured images are modeled for road texture, and the density of each group of point clouds is calculated. Finally, the effect of the shooting method on the point cloud density is discussed, and the average distance between the point clouds is calculated to verify the feasibility of the method. The results show that under the same test board, the larger the proportion of the texture feature interest region in the middle of the image, the larger and smaller the point cloud density; point cloud density is related to the spacing between point clouds. The higher the point cloud density, the smaller the average distance between the point clouds. The feasibility of the road texture modeling method based on the smart phone imaging platform is verified.]]></description>
      <pubDate>Fri, 20 Feb 2026 15:28:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/2613043</guid>
    </item>
    <item>
      <title>Pavement Surface Properties Consortium Phase IV - Improving Safety and Saving Lives through Pavement Surface Optimization</title>
      <link>https://trid.trb.org/View/2672598</link>
      <description><![CDATA[Functional pavement considerations are fundamental to the performance and management of pavements. In addition to structural and durability requirements, an optimum pavement wearing surface should provide a combination of a good riding quality, adequate safety, and a low noise level. All these responses are highly influenced by the various components of the pavement surface texture. Previous phases of the program demonstrated that a collaborative research program can provide an accessible and efficient way for highway agencies and other organizations to conduct research on pavement surface properties. The collaboration helped the participating agencies explore new technologies, verify the operation and accuracy of the equipment currently used for evaluating pavement surface properties, and enhance the methodologies for developing and implementing proactive friction management programs.
OBJECTIVE: The mission of the Surface Properties Consortium has been to conduct applied research focused on enhancing the level of service provided by the roadway transportation system by optimizing pavement surface characteristics.]]></description>
      <pubDate>Thu, 19 Feb 2026 18:59:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2672598</guid>
    </item>
    <item>
      <title>Improve pavement surface distress and transverse profile data collection and analysis, Phase III</title>
      <link>https://trid.trb.org/View/2666773</link>
      <description><![CDATA[The technical capabilities of systems to collect and analyze pavement surface distress and transverse profile (PSDATP) have increased dramatically in the last 5-10 years. Many state highway agencies (SHAs) are in the process of assessing the procurement of equipment/systems or procuring vendor services for network and project level pavement condition assessments. The collection of quality PSDATP is critical for pavement management and design. The current national and State efforts to develop and refine pavement performance measures highlight the high value provided by quality PSDATP. The implementation of new project delivery methods with medium- to long-term maintenance agreements (Design Build Maintain, Design Build Operate, etc.) justifies the need for high-quality PSDATP data. Accurate and repeatable measures are essential for proper planning and the allocation of funding. The implementation of the Mechanistic Empirical Pavement Design Guide (MEPDG) highlights the need for quality PSDATP to maximize the potential of the MEPDG and all other pavement design models. The emphasis on preventive pavement maintenance activities provides the opportunity for additional value from greater resolution of pavement surface distress quantification. TPF-5(299) and TPF-5(399) comes to end in 2026, and this pooled fund study will continue the work of that pooled fund study. The 24 State Highway Agencies of TPF-5(399) support starting this new pooled fund study. The activities of the pooled-fund study will be communicated with other appropriate committees and groups in the pavement community, such as, the Road Profiler User Group, the Federal Highway Administration (FHWA), the American Association of State Highway and Transportation Officials (AASHTO) Committee on Materials and Pavements (COMP), National Cooperative Research Program (NCHRP) and the Transportation Research Board (TRB). The AASHTO COMP currently manages several standards related to pavement surface characteristics measurement. Many of these standards continue to need refinement and updating. This pooled-fund study is being established to provide direction and funding to unify the strategies, support implementation efforts, and promote best practices that improve the accuracy and repeatability of the data collection and analysis systems, as well as advance the understanding of PSDATP measurements. It is expected that this study will be completed within 5 years.

OBJECTIVES: Improve the Quality of Pavement Surface Distress and Transverse Profile Data Collection and Analysis by assembling SHAs, the FHWA, and industry representatives to: Identify data collection integrity and quality issues; Identify data analysis needs; Suggest approaches to addressing identified issues and needs. Based on this information, the SHAs and the FHWA will: Initiate and monitor projects intended to address identified issues and needs; Disseminate results; Assist in solution deployment 
]]></description>
      <pubDate>Mon, 09 Feb 2026 19:52:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/2666773</guid>
    </item>
    <item>
      <title>Trial of laser-based requirements for ride quality and texture depth of newly laid asphalt surfaces</title>
      <link>https://trid.trb.org/View/2635350</link>
      <description><![CDATA[National Highways engaged TRL Limited to explore ways of constructing smoother pavements on England’s Strategic Road Network (SRN). Improved standards were to be developed for cost-effective changes in pavement construction and maintenance. The research team developed a compliance method for the smoothness of pavement surfaces, that utilizes methods for non-contact measurements. The compliance process's aptness was tested and the trial results are presented.]]></description>
      <pubDate>Fri, 06 Feb 2026 13:54:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2635350</guid>
    </item>
    <item>
      <title>Research on multi-scale damage behavior and structural evolution of hardened cement paste by high-power nanosecond pulsed laser: Based on laser flux range in airport pavement engineering</title>
      <link>https://trid.trb.org/View/2635592</link>
      <description><![CDATA[As a key component of the airport runway surface, the cement paste is considered the primary sensitive area under high-power laser cleaning due to its relatively low thermal stability compared with coarse and fine aggregates. This study is aimed at gaining a fundamental understanding of the interaction between a 1064 nm nanosecond pulsed laser and cement paste, and to deeply explore the correlation between the laser energy density range based on the cleaning function of airport pavement engineering and the composition evolution of cement paste, as well as multi-scale structural damage and mechanical properties (macro-meso-micro). When the laser injection volume is 0–8 J/cm2, no apparent macroscopic morphological damage or reduction in overall mechanical properties is observed, but microscopic morphological changes are induced. Water vapor and carbon dioxide are released from the micrometer-affected zone of the upper surface layer. The dehydration of C-S-H and the decomposition of calcium hydroxide result in the formation of a reticular, woven structure and the collapse of large gel pores (LGP). The local mechanical properties of the cement paste are reduced (nanoindentation modulus/hardness), with a decrease in the proportion of 0–50 nm pore size and an increase in the proportion of 50–100 nm pore size. Obviously, morphological damage can be observed when the energy density is above 8 J/cm2. The surface of the cement paste gradually changes from gray to a reddish-brown color. Under low light spot overlap rate, the reddish-brown substance is directly crushed into powder (destructive evolution). In contrast, it transforms into a smooth film under a high light spot overlap rate (non-destructive evolution). At 16 J/cm2, the reddish-brown substance reaches its maximum. The uneven thermal shrinkage of the unhydrated cement particles and C-S-H leads to a columnar structure on the surface. The deep brown substances were identified as α-FeOOH and CaFe5O7 through XRD and Raman spectroscopy characteristics. The research results can provide important references for promoting the application of laser cleaning technology in airport runways and broader road engineering.]]></description>
      <pubDate>Wed, 04 Feb 2026 16:28:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/2635592</guid>
    </item>
    <item>
      <title>Silane Coupling Agent-treated Steel Slag for Sustainable Asphalt Pavements: Performance Optimization and Feasibility Assessment</title>
      <link>https://trid.trb.org/View/2635584</link>
      <description><![CDATA[The rapid growth of the steel industry has led to increased steel slag (SS) production in China. However, its low utilization rate has resulted in large-scale stockpiling and exerted pressure on the environment. To achieve the efficient resource utilization of SS in pavement engineering, this study employed a silane coupling agent (SCA) to treat SS and explored its application in asphalt mixtures. Microscopic tests were conducted to investigate the interfacial modification mechanism of SCA-treated SS (SSS). SSS was used to replace 40, 50, 60, and 70% of basalt coarse aggregate by volume. A series of tests was performed to systematically analyze the effect of SSS content on mixture performance and assess its feasibility in asphalt mixtures. The results showed that SCA formed a polymer film on the SS surface, effectively preventing moisture intrusion. The volumetric swelling rate of SSS asphalt mixtures (SSSAM) was reduced by more than 65%, significantly improving the volumetric stability and moisture resistance of the mixture. SSS content was a key factor in mixture performance. When the SSS content reached 50%, the comprehensive pavement performance achieved an optimum level. The dynamic stability, dynamic modulus (20°C, 10Hz), and fatigue life (at 0.2 strain level) were 2.20, 1.29, and 1.43 times those of the basalt asphalt mixture, while low-temperature cracking resistance met the specification requirements. Comprehensive analysis demonstrated that SSSAM significantly reduces stockpiling and environmental management costs while maintaining the leaching of harmful substances within acceptable limits. Although initial construction costs and carbon emissions exceed those of conventional mixtures, the superior performance of SSSAM could reduce long-term pavement maintenance frequency. This supports large-scale application of SSSAM in pavement surface layers, advancing resource conservation and sustainable infrastructure development.]]></description>
      <pubDate>Wed, 04 Feb 2026 16:28:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/2635584</guid>
    </item>
    <item>
      <title>Pavement skid resistance evaluation incorporating tire size effect</title>
      <link>https://trid.trb.org/View/2643665</link>
      <description><![CDATA[Pavement skid resistance is a critical parameter for road safety, influencing vehicle handling and reducing accident risks, particularly under wet weather conditions. This study examines the need for considering the effect of tire size in pavement skid resistance evaluation. The impact of tire size on skid resistance is investigated using finite element modeling of three standard smooth tread test tires: ASTM E524, ASTM E1551, and ASTM E1844. The results show that, under identical testing conditions, including consistent water film thickness, vehicle speed, tire inflation pressure, and tire loading, tire-pavement skid resistance decreases as tire size increases. Among the tires tested, the smallest-size ASTM E1844 tire consistently demonstrated the highest skid resistance, followed by the ASTM E1551 tire and the ASTM E524 tire. This study offers valuable insights into the role of tire size in pavement skid resistance assessment. The findings highlight that different test tire sizes produce varying skid resistance results even under the same conditions, emphasizing the importance of tire-size effect in pavement skid resistance evaluations.]]></description>
      <pubDate>Thu, 29 Jan 2026 17:02:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2643665</guid>
    </item>
    <item>
      <title>Back-calculating structural internal damage of semi-rigid asphalt pavements using RIOH test track surface deflection measurements</title>
      <link>https://trid.trb.org/View/2643649</link>
      <description><![CDATA[Accurately assessing internal structural damage in asphalt pavements is critical for optimizing maintenance strategies and extending service life. Falling Weight Deflectometer (FWD) results are commonly used to quantify reductions in structural bearing capacity and to back-calculate degraded layer moduli. However, these reductions may also result from environmental and aging effects, complicating interpretation. This study integrates the finite element method, artificial neural networks, and genetic algorithms to estimate damage density from FWD results and directly evaluate structural degradation. The method is applied to six pavement sections from the RIOH test track subjected to 78 million equivalent single axle loads (ESALs). A dual-parameter model describes the evolution of back-calculated damage density, with surface crack density used for independent validation. Results show that damage evolution strongly correlates with surface cracking, particularly within the first 40 million ESALs. Thinner asphalt layers and recycled mixtures accelerate damage accumulation, while permeable asphalt layers produce a stepwise damage progression consistent with surface crack development.]]></description>
      <pubDate>Thu, 29 Jan 2026 17:02:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2643649</guid>
    </item>
    <item>
      <title>Energy-Efficient Tunnel Paving Materials Based on Road Surface Luminance</title>
      <link>https://trid.trb.org/View/2613621</link>
      <description><![CDATA[To address the issue of excessive energy consumption in tunnel lighting, this study investigates the use of energy-efficient tunnel paving materials based on road surface luminance observed by drivers, which is applied by the reflection characteristics of the road surface. Using scaled model experiments and DIAlux lighting simulations, the luminance performance of nine types of pavement materials and three types of sidewall materials was systematically evaluated. The results show that sidewall materials primarily enhance lateral visual comfort and contribute minimally to improving pavement luminance. Even with high reflectance sidewalls at a reflectance level of 0.8, the luminance observed on the pavement increased by only 7.8 percent. In contrast, pavement materials with diffuse reflection can significantly improve both luminance and uniformity. Light-colored stones pavements demonstrated the highest energy-saving performance, achieving a reduction of up to 28 percent in energy consumption per kilometer when the embedding amount reached 6  kg/m². Additionally, poured semiflexible (PSF) pavement material also improves luminance and uniformity of tunnel pavement, yielding energy savings of up to 18%.]]></description>
      <pubDate>Mon, 26 Jan 2026 14:44:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/2613621</guid>
    </item>
    <item>
      <title>A study of the efficiency of photocatalytic asphalts in reducing NOx pollution: from laboratory to semi-real scale</title>
      <link>https://trid.trb.org/View/2643743</link>
      <description><![CDATA[This study evaluates the efficiency of three photocatalytic materials for urban pavements on a semi-real scale. The realistic approach allows the material to be assessed against vehicle loads and runs over the service lifetime of the pavement, giving an idea of its durability of the performance under traffic passage. In practice, a series of functional and durability tests were carried out both in the laboratory and through an Accelerated Pavement Testing (APT) facility. On the one hand, the laboratory work made it possible to evaluate the photocatalytic efficiency (according to RhB degradation and ISO 22197-1) as a function of the incorporation mode of the material. On the other hand, the APT measurements allowed the efficiency and durability of the photocatalytic material to be monitored over the equivalent of up to 20 years of heavy-duty traffic. The material does not impact significantly the skid resistance of the pavement and does not compromise road safety. The data demonstrated that the most efficient photocatalytic material is the one sprayed on the pavement surface, with an average NOx removal of 18 ± 4%, but the efficiency would degrade due to the passage of heavy-duty vehicles in the first quarter of its life.]]></description>
      <pubDate>Mon, 26 Jan 2026 08:41:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2643743</guid>
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