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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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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
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    <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>Internal Curing with Fine Light Weight Aggregates (FLWA) Created from Unsuitable Coal Combustion Ash (CCA)</title>
      <link>https://trid.trb.org/View/2672100</link>
      <description><![CDATA[This work studies the potential use of fine lightweight aggregates (FLWA) created from ‘as received’ landfill condition coal combustion ash (CCA), referred to as CCA-FLWA, for concrete internal curing applications. The innovative CCA-FLWA is manufactured using high-temperature sintering like available industrial kilns. To manufacture CCA-FLWA with desired properties for internal curing, this work first optimizes the manufacturing process and assesses CCA-FLWA properties for concrete applications. Second, concrete samples with CCA-FLWA are prepared and their internal curing performance is assessed in comparison to available FLWA in the market. Finally, a cost analysis and feasibility of implementation for future industrial application of manufactured CCA-FLWA are performed. This work demonstrates that FLWA with desired internal curing properties can be manufactured using CCA waste streams for concrete applications. Not only does CCA-FLWA meet ASTM requirements for FLWA, but also concrete made using CCA-FLWA shows promising fresh and hardened properties for internal curing applications. The industrial manufacturing of CCA-FLWA is also found feasible when compared to commercial FLWA to transfer the technology to the concrete industry.]]></description>
      <pubDate>Wed, 25 Feb 2026 16:28:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/2672100</guid>
    </item>
    <item>
      <title>Evaluation of Performance of Coal Ash in Florida Structural Concrete</title>
      <link>https://trid.trb.org/View/2663281</link>
      <description><![CDATA[Recent coal-fired power plant closures resulted in limited availability of fresh fly ash in some regions of the United States of America. This combined with stricter environmental regulations has led to national specifications being modified to allow the use of coal bottom ash in addition to coal fly ash as a supplementary cementitious material in making concrete. Coal bottom ash is different from coal fly ash in its chemical, physical and mineralogical composition. The literature review conducted in this study identified variability in performance of coal ash that can be related to variability in the available sources of the collected coal ash; namely, landfills, lagoons or freshly collected bottom ash. The findings indicate that the work is needed to ensure consistent performance of coal ash collected from variable sources. It is recommended that a study on coal ash performance be initiated to ensure adequate and consistent performance and durability of structural concrete elements in the state of Florida using coal ash as a supplementary material.]]></description>
      <pubDate>Fri, 20 Feb 2026 08:49:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/2663281</guid>
    </item>
    <item>
      <title>Preparation and performance study of coal gangue aggregate permeable concrete bricks (CGAPCBs)</title>
      <link>https://trid.trb.org/View/2618013</link>
      <description><![CDATA[This paper proposes using spontaneous combustion coal gangue aggregate (SCGA) and rock roadway excavation gangue aggregate (REGA) to replace natural aggregate (NA) in producing permeable concrete (SCGAPC/REGAPC) and bricks (SCGAPCBs/REGAPCBs). Optimal mix proportion of SCGAPC was obtained by orthogonal test, Compressive strength and permeability coefficient were 25.1 MPa, 2.67 mm·s⁻¹ respectively when aggregate-cement ratio (A/C), water-cement ratio (W/C) and reinforcing agent content (RAC) were 3.2, 0.23 and 6.0%, meeting the requirements for non-vehicular pavement. SCGAPC without slurry leakage or bottom sealing was prepared when slurry yield stress, fluidity were 22.6 25.0 Pa, 210 220 mm. By single factor test, compressive strength, flexural strength, splitting strength and permeability coefficient of SCGAPCBs were 41.1 MPa, 4.1 MPa, 3.3 MPa and 1.5 mm·s⁻¹ when proportion of coarse and fine aggregates, forming pressure and pressure-holding time were 4:6, 4 MPa and 35 s, meeting the requirements for vehicular pavement. Flexural strength over 5 MPa, grade of freeze-thaw resistance and permeability up to D50 and B, grinding pit depth below 5mm of CGAPCBs were prepared, meeting the requirements for parking lot pavement.]]></description>
      <pubDate>Mon, 09 Feb 2026 13:55:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2618013</guid>
    </item>
    <item>
      <title>Transportation Infrastructure Needs in the Central Appalachian Basin to Support CORE-CM</title>
      <link>https://trid.trb.org/View/2641776</link>
      <description><![CDATA[With demand for coal from the Central Appalachian Basin waning, coalitions and organizations throughout the region have sought to diversify the region’s economy. However, the potential exists to use coal and coal-based resources to produce new and innovative products and kick start economic growth in the basin. This includes carbon ore, rare earth and critical minerals (CORE-CM), other minerals, and waste streams. If the region is to take advantage of these economic growth opportunities, transportation infrastructure must be developed and maintained in a sound condition. Reliable roads, highways, and bridges provide rural areas with access to capital, labor, and markets for goods. This study looks at lessons learned from local and state government experiences with energy exploration and extraction and identifies how current infrastructure could support CORE-CM activities. The Central Appalachian Basin’s transportation networks can support increased freight movement, but governments must implement strategies that balance maintenance of existing infrastructure with investments in new facilities. Data-driven decision making can lead to the adoption of policies that support region-wide economic development. Recommendations are advanced related to freight planning, statewide multimodal transportation planning, virtual weigh station technology, and funding strategies.]]></description>
      <pubDate>Mon, 05 Jan 2026 09:52:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/2641776</guid>
    </item>
    <item>
      <title>Investigation of the effect of coal char on cement-treated bentonite-sand mixtures for pavement applications</title>
      <link>https://trid.trb.org/View/2608529</link>
      <description><![CDATA[Coal-derived char, a byproduct of coal pyrolysis, is a porous, carbon-rich material with potential to enhance cement-treated soils. This study examined its effect on problematic soils containing expansive clay (sodium bentonite), focusing on mixtures for subgrade (25% bentonite, 75% sand, 1% cement denoted as 25–75 mix) and sub-base/base (50% bentonite, 50% sand, 5% cement denoted as 50–50 mix) applications. Char was added at 0, 10, 20, and 40% by cement weight. Tests included Atterberg limits, optimum water content (OWC), unconfined compressive strength (UCS), triaxial compression, unsoaked California bearing ratio (CBR), consolidation, and freeze–thaw. UCS increased with curing time, cement, and char content. Consolidation and freeze–thaw parameters, like compression coefficient and weight loss, respectively, improved with cement and char addition. With cement treatment, CBR values rose by 2.5 times for the 25–75 mix, exceeding the “excellent subgrade” range, and 3.5 to 4 times for the 50–50 mix, surpassing “high-quality base” standards. However, char addition did not further increase CBR, likely due to its porous nature, making samples more penetrable. Nevertheless, all CBR values exceeded AASHTO recommendations. Overall, coal char shows promise for improving cement-treated soils in environmentally friendly pavement applications.]]></description>
      <pubDate>Tue, 02 Dec 2025 09:56:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2608529</guid>
    </item>
    <item>
      <title>Investigation of early vehicle-bridge coupling vibration on the properties and microstructure of lightweight UHPC incorporating coal gangue ceramsite</title>
      <link>https://trid.trb.org/View/2590828</link>
      <description><![CDATA[This study investigates the effects of various vibration parameters (amplitude, frequency, and duration) on the mechanical properties, volume stability, and durability of lightweight UHPC incorporating coal gangue ceramsite (CGC). Additionally, it provides a systematic analysis of the nano-mechanical properties and microstructural evolution of the interfacial transition zone (ITZ). Results indicate that low-energy and medium-energy vibration applied before initial setting reduces ITZ and matrix porosity, promotes matrix hydration and the internal curing water release from CGC, leading to the formation of high-density C-S-H gels. Consequently, this significantly improves compressive strength, reduces drying shrinkage (up to 10.61 %) and increases durability (up to 53.87 % reduction in electrical flux). Conversely, high-energy (HE) vibration before initial setting results in deteriorated fiber orientation and distribution, increased porosity in the ITZ and matrix, and reduced density of C-S-H gels. This markedly diminishes flexural and bond strengths by 10.91 % and 8.05 %, respectively. The initial to final setting (IF) stage affects the macroscopic properties the most significantly of all stages. During the IF period, increasing vibration energy has a minimal impact on fiber and aggregate distribution. However, it transforms the ITZ from a porous framework to a micro-cracked structure, increasing the proportion of low-density C-S-H gels. Furthermore, vibration during the IF stage causes uneven water release from CGC, disrupting the formation of the spherical “arched-shell” structure, which impairs mechanical properties (especially HE-vibration reduces the flexural strength by around 17 %), shrinkage and durability. This study provides a theoretical foundation for applying CGC-UHPC in bridge repair projects without traffic interruption.]]></description>
      <pubDate>Thu, 16 Oct 2025 17:02:35 GMT</pubDate>
      <guid>https://trid.trb.org/View/2590828</guid>
    </item>
    <item>
      <title>Performance of high-volume coal combustion residual-based concrete pavement: an experimental evaluation of engineering properties, durability, microstructure, cost, and environmental impacts</title>
      <link>https://trid.trb.org/View/2590810</link>
      <description><![CDATA[In line with the critical need to increase construction sector sustainability, this study conducts a pioneering exploration of the practical potential of using high-volume coal-combustion-residue-based concrete in pavement applications. The novel mixtures examined in this research incorporate fly ash (FA) and bottom ash (BA) as respective replacements for Portland cement (at 50 % by weight, T50X0 mix) and natural sand (at 50 % and 100 % by volume, T50X50 and T50X100 mixes) in concrete. The results show the modified mixtures, while achieving lower strengths at the earliest curing age, significantly improve in strength at later ages, with T50X50 and T50X100 respectively achieving 6.7 % and 2.1 % higher compressive strength values and 31.5 % and 11.1 % higher flexural strength values than the control (traditional concrete) at 56 days of curing age. Moreover, durability test results show reduced drying shrinkage in the modified mixtures, with T50X100 showing 44.6 % less shrinkage than the control at 56 days; UPV test results show a denser concrete matrix in the modified mixtures, with T50X50 exceeding the control by 5.3 % at 56 days; and RCPT results show substantial improvements in chloride ion resistance in the modified mixtures, with T50X100 earning RCPT values of 57.4 % and 72.6 % below the control at 28 and 56 days, respectively. In addition, microstructural analyses confirm the microstructures of the modified mixtures as more refined and homogeneous than the control. Finally, economic and environmental assessments highlight significant reductions in material costs, CO2-eq emissions, and embodied energy consumption (EC) for the modified mixtures, with T50X100 achieving 36.5 % lower material costs, 60.5 % lower CO2-eq emissions, and 45.7 % lower EC than the control. The multi-criteria assessment identifies T50X50 as the most suitable mixture for use in the construction of level-4 rural area concrete pavement due to its meeting all technical requirements under Vietnamese national standards. The findings of this study underscore the transformative potential of FA and BA in enhancing concrete sustainability, offering a groundbreaking approach to future construction projects.]]></description>
      <pubDate>Fri, 26 Sep 2025 09:07:40 GMT</pubDate>
      <guid>https://trid.trb.org/View/2590810</guid>
    </item>
    <item>
      <title>Evaluation the properties and runoff pollutants removal efficiency by biochar-coal gangue permeable brick</title>
      <link>https://trid.trb.org/View/2578696</link>
      <description><![CDATA[In order to investigate the physical properties and runoff pollutants removal efficiency by different porosities and materials of permeable bricks, traditional permeable bricks (TB), coal gangue permeable bricks (GB) and biochar-coal gangue permeable brick (CGB) were prepared. These permeable bricks, prepared by processes such as mixing, pressing and curing, are expected to be used in road paving, square construction and other fields to enhance permeability. The results showed that the physical properties of permeable bricks were mainly affected by porosity, which permeable bricks with 10 % porosity showed higher compressive strength and water retention. With the biochar content of 1–3 %, the compressive strength and water retention of permeable brick was higher than that of GB, but the strength would be compromised with the content exceeds furthermore. On the other way, the removal efficiency of runoff pollutants was mainly determined by the brick materials, while CGB showed the highest removal efficiency for chemical oxygen demand (COD), ammonia nitrogen (NH₄+-N), total nitrogen (TN) and total phosphorus (TP). Furthermore, the correlation coefficients indicated that the removal efficiency of COD by permeable brick was also affected by permeability coefficient greatly. The negative correlation between COD and permeability coefficient was confirmed with R²= 0.92. The removal efficiency of TN by permeable brick was least affected by permeability coefficient, which was mainly adsorbed by brick materials. In overall, CGB with the porosity of 10 % and the biochar content of 3 % had the best performance for both physical properties and runoff pollutants removal efficiency. This research promotes the development of green building materials and provides new design ideas for permeable brick.]]></description>
      <pubDate>Mon, 08 Sep 2025 14:54:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/2578696</guid>
    </item>
    <item>
      <title>Enhancement of the Aging Resistance Performance of Asphalt Binder Using Activated Coal Gangue Waste and Determination of the Influence Mechanism Based on Interfacial Interaction Ability</title>
      <link>https://trid.trb.org/View/2563625</link>
      <description><![CDATA[This study conducted thermal activation approach to modify coal gangue (CG) waste from 450°C to 900°C and applied it to enhance aging resistance performance of asphalt binder. The surface morphology, mineral components, and size distribution of original and activated CG were analyzed. After 10, 20, and 40 h in a pressure aging vessel (PAV), rheological and chemical aging behaviors of various CG asphalt mastics (CGAMs) were characterized. Meanwhile, the K-B-G* parameter was calculated to measure interfacial interaction ability between asphalt and different CG fillers, aiming to establish correlation with aging indexes. The multiscale results showed that the thermal activation process on CG waste results in particle size decreasing, surface roughness increasing, and crystal lattice transferring. These variances contribute to increasing the interaction area of CG particles with asphalt binder. There is a high relation between K-B-G* and the aging indexes, demonstrating that the stronger the asphalt–filler interaction ability, the better the aging resistance property of asphalt mastic. Thermal activation on CG waste has a positive influence on enhancing the aging resistance property of corresponding asphalt mastic, and the suggested calcination temperature is 750°C.]]></description>
      <pubDate>Wed, 30 Jul 2025 09:56:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/2563625</guid>
    </item>
    <item>
      <title>Experimental assessment of freeze–thaw characteristics and microscopic mechanisms of coal-based solid waste improved loess filler</title>
      <link>https://trid.trb.org/View/2564784</link>
      <description><![CDATA[To tackle freeze–thaw damage in loess layers by seasonal freeze–thaw cycles (FTC) and the growing coal-based solid waste crisis in Northwest China, the authors propose using coal-based solid waste to enhance loess for more stable, sustainable infrastructure. This paper investigates the freeze–thaw behaviors and microscopic mechanisms of loess modified with 6%, 15% coal gasification slag (CGS) and 30%, 50% coal gangue (CGA), using FTC tests, SEM analysis, and CT scans. Key aspects were analyzed include frost heave, thaw settlement, temperature, moisture distribution, and microstructural changes. The results show that adding 15% CGS reduces average frost heave and thaw settlement by 72.6% and 70.8% during the first 2 FTC, while 50% CGA cuts frost heave by 62.5% over 5 FTC, demonstrating strong potential for freeze–thaw resistance. The addition of CGS and CGA can also reduce temperature fluctuation and thermal conductivity of loess, enhancing the internal temperature stability. Moreover, adding 50% CGA could help regulate water content distribution after FTC and densify the structure of improved loess, while adding CGS leads to aggregates formation within modified loess particles.]]></description>
      <pubDate>Thu, 24 Jul 2025 11:29:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2564784</guid>
    </item>
    <item>
      <title>Enhancing rheological properties and self-healing performance of asphalt mastic using coal gasification slag</title>
      <link>https://trid.trb.org/View/2556156</link>
      <description><![CDATA[This study examines the possibility of employing coal gasification slag as filler to improve rheological behavior and self-healing efficiency of asphalt mastic. Coarse slag (CS) and fine slag (FS), two slag variants, were evaluated as alternatives to limestone filler (LF) at replacement ratios of 10 %, 20 %, 30 %, 40 %, and 50 % with particle size smaller than 0.075 mm. A comprehensive analysis was conducted using various methods: X-ray diffraction (XRD) to characterize mineral compositions, dynamic shear rheometer (DSR) to analyze the high-temperature performance, bending beam rheometer (BBR) to assess low-temperature behavior, and vector network analyzer system (VNA) to examine electromagnetic parameters. Furthermore, the initial temperature of self-healing and its healing capability were assessed. The outcomes revealed that both CS and FS effectively enhanced the capability to resist high-temperature permanent deformation of asphalt mastic while having a minor negative impact on low-temperature behavior. CS and FS substantially affected the flow behavior of asphalt and increased the initial healing temperature. Moreover, coal gasification slag significantly improved the crack-healing ability of the asphalt mastic, although excessive FS content could reduce these advantages. Optimal self-healing properties were achieved with asphalt mastic containing 50 % CS or 40 % FS. Electromagnetic testing revealed that CS and FS exhibited higher electromagnetic impedance compared to LF, enabling more efficient conversion of microwave radiation energy into thermal energy. Cost analysis results demonstrated significant financial benefits from the implementation of this utilization process. In general, this study highlights a promising approach to improving asphalt mastic performance while providing an innovative and sustainable method for recycling coal gasification slag, contributing to efficient waste utilization.]]></description>
      <pubDate>Fri, 20 Jun 2025 11:58:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2556156</guid>
    </item>
    <item>
      <title>Effective Utilization of Coal Gangue for Stabilizing Black Cotton Soil: Geotechnical Performance and Microstructural Insights</title>
      <link>https://trid.trb.org/View/2516441</link>
      <description><![CDATA[Coal gangue (CG) is a waste generated during coal mining, accounting for 10–25% of the coal extracted. Black cotton soil (BCS) detrimentally affects superstructures due to its volume changes and hence is a persisting challenge. To suppress this, there is an utmost need to enhance the strength of BCS. In this study, the synergetic effects of CG and lime as stabilizers for BCS are examined. The experimental investigation includes evaluating critical geotechnical properties of BCS, specifically unconfined compressive strength (UCS) and durability to understand the extent of blended stabilization. The experimental design incorporates CG dosages of 10%, 20%, and 30% of the dry weight of BCS along with lime dosages of 4%, 6%, and 8%. Findings reveal a notable improvement in the UCS and durability of BCS when incorporating 20% CG with 6% lime. Also, the California bearing ratio (CBR) test was performed on the optimum mixture for applicability as subgrade and subbase material. Mineralogical and microstructural analysis, carried out using X-ray diffraction (XRD) and Scanning electron microscope (SEM), respectively, substantiates the strength enhancement is due to the formation of cementitious compounds. Thus demonstrating the potential of CG blended lime as an effective solution for soil stabilisation. This study offers a promising avenue for construction in challenging geotechnical environments.]]></description>
      <pubDate>Tue, 27 May 2025 09:33:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2516441</guid>
    </item>
    <item>
      <title>Laboratory study of the effect of coal waste filler on short- and long-term fracture properties of warm mix asphalt (WMA): Towards the production of sustainable pavements</title>
      <link>https://trid.trb.org/View/2545074</link>
      <description><![CDATA[Transverse cracks (with tensile origin) and oblique cracks (with tensile + tear and tear origins) on flexible asphalt pavement (FAP) develop and propagate under time-dependent environmental conditions and long-term repeated loading. These cracks, divided into low-temperature top-down cracks (LTTDC) and intermediate-temperature top-down cracks (ITTDC), cause a decrease in the course surface quality over time. The present study aimed to introduce sustainable warm mix asphalt (WMA) mixes using an environmentally friendly additive named Fresh Jig Coal Solid Waste (FJCSW). Three mixtures containing 0% FJCSW (WF0), 50% FJCSW (WF50), and 100% FJCSW (WF100) were prepared and tested using the three-point edge notched disc bend (ENDB) test. This evaluation focused on three types of cracks: transverse cracks with a tensile origin (mode I), oblique cracks with tensile+tear origins (mode I+III), and oblique cracks with a tear origin (mode III). The mixes were subjected to 0 and 1 freeze-thaw (F-T) damage. Finally, an economic and environmental analysis was conducted on the asphalt pavement thickness reduction, utilizing the resilient modulus (Mr) test. The results showed that the WF50 had better short- and long-term behavior against transverse cracks with tensile origin (mode I), oblique cracks with tensile+tear origin (mode I+III), and oblique cracks with tear origin (mode III). Also, the decline in thickness owing to the boost in the Mr led to economic benefits and reduced pollutants emissions such as carbon dioxide (CO₂), nitrogen oxides (NOₓ), methane gas (CH₄), volatile organic compounds (VOCs), sulfur dioxide (SO₂), and particulate matter (PM10) in the various construction stages.]]></description>
      <pubDate>Wed, 21 May 2025 16:54:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/2545074</guid>
    </item>
    <item>
      <title>Study of the fracture properties of asphalt mixtures using Fresh Jig Coal Waste (FJCW) as a filler replacement under short-term and long-term conditions</title>
      <link>https://trid.trb.org/View/2510741</link>
      <description><![CDATA[Pavement maintenance is a repair operation on a damaged asphalt pavement, defined to increase the life of the road. One of the ways to reduce maintenance costs is to improve the quality of the pavement by increasing the quality of the course surface. Increasing the quality of pavement can be achieved through the addition of environmentally friendly additives to improve the quality of the surface and prevent the wastage of natural resources. For this purpose, in this study, Fresh Jig Coal Waste (FJCW) was replaced with stone material filler in proportions of 0 %, 50 %, and 100 %. A consistent numerical-laboratory program was defined in which the short-term and long-term fracture behavior of three types of hot mix asphalt (HMA) were investigated using semicircular-bending (SCB) under mode II (contains 0-degree crack), mode I/II (contains 15-degree crack), and mode I (contains 35-degree crack) at low and intermediate temperatures. The finite element method was used for the numerical modeling of the sample under mixed mode I/II. Finally, the SCB samples were conditioned under a freeze-thaw (F-T) cycle to estimate the behavior of the HMA mixture during maintenance. The results of the fracture tests revealed that the mix with an equal replacement ratio of filler and coal waste had the best performance during operation and maintenance, indicating an increase in the quality of the course surface and a reduction in pavement maintenance costs. From the perspective of loading mode, the findings showed that samples under mode I/II showed the lowest fracture resistance, indicating the importance of the impact of crack deviation (relative to the vertical plane) in the design of asphalt mixtures. From the viewpoint of fracture indices, the results of this research give a deep insight into the scientific community regarding the production of environmentally friendly asphalt mixtures that can contribute to the socio-economics of pavements. Although the fracture resistance and fracture stiffness of the specimens were improved in different conditions, the decrease in the flexibility of the samples with the increase of FJCW dosage aggravated the brittle fracture potential. Therefore, a mixture with a replacement ratio of 50 % FJCW was selected for design purposes. From the point of view of loading mode, the findings showed that different mixtures had the lowest fracture resistance, fracture stiffness, and fracture flexibility under mode I, indicating the importance of the impact of angled cracks (relative to the vertical plane) in the design of asphalt mixtures. Also, the results indicated the destructive effect of F-T in reducing various indicators; however, the damage reduction caused by the presence of FJCW under different modes was confirmed by the damage factor (DF) index. From the point of view of fracture indices, choosing an HMA mixture with a 50 % replacement ratio of FJCW in the construction of flexible pavements can reduce the overall maintenance costs at the beginning of operation until the end of the fourth year after operation, in addition to contributing to the sustainable development of transportation infrastructure.]]></description>
      <pubDate>Thu, 10 Apr 2025 09:21:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2510741</guid>
    </item>
    <item>
      <title>Effect of organic coal gangue powder with terminal active isocyanate groups on the performance of asphalt and its mixture</title>
      <link>https://trid.trb.org/View/2503062</link>
      <description><![CDATA[To enhance both the utilization efficiency of solid waste coal gangue and the overall performance of asphalt materials, hexamethylene diisocyanate (HDI) was employed to organically modify coal gangue powder (CGP) so as to prepare organic coal gangue powder with terminal active isocyanate groups (HDI-CGP). The structure, particle size and micro morphology of HDI-CGP were characterized and tested. The influence of HDI-CGP on the physical properties, rheological properties, aging properties, and road performance of asphalt materials was investigated. Comparative analysis was made using octadecyl isocyanates (ODI, a monoisocyanate) modified CGP (ODI-CGP). The results confirmed successful preparation of HDI-CGP and ODI-CGP without damaging the crystal structure of coal gangue. HDI-CGP and ODI-CGP exhibited reduced agglomeration and particle size compared to unmodified CGP. The compatibility and stability of both HDI-CGP and ODI-CGP with asphalt were superior to that of CGP. HDI-CGP, specifically, interacted with active groups in asphalt, generating liked cross-linked structures. HDI-CGP was more efficacious in bolstering the high-temperature stability of asphalt (evidenced by higher softening point, complex modulus at 30–80°C, and rutting resistance), while minimally affecting low-temperature properties, such as low-temperature ductility and bending creep performance. HDI-CGP also enhanced aging resistance of asphalt binder and optimized rutting, cracking, and moisture damage resistance of asphalt mixture compared to CGP and ODI-CGP.]]></description>
      <pubDate>Thu, 13 Mar 2025 09:24:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/2503062</guid>
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