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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" />
    <description></description>
    <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>
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      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Unveiling the role of size characteristics of recycled rubber-polyethylene elastomers on polymer-asphalt interaction and asphalt rheology</title>
      <link>https://trid.trb.org/View/2721197</link>
      <description><![CDATA[Upcycling waste tires and recycled polyethylene (rPE) into asphalt offers a sustainable solution. However, poor compatibility between crumb rubber (CR), rPE and asphalt limits practical application. Accordingly, the size characteristics of modifiers is critical to polymer-asphalt interaction and the resulting rheological behavior, yet remains insufficiently understood in rubber-polyethylene elastomers. In this study, CR and rPE were extruded and cryogenically pulverized to obtain the thermo-mechanical rubber-polyethylene elastomers (TRPE) and micronized elastomers (mRPE). The microphase interaction, phase separation, and rheological behavior of modified asphalt were evaluated. The results indicate that TRPE already establishes a relatively well-dispersed polymeric phase in asphalt, while further micronization improves microstructural uniformity and reduces the softening point difference to 0.8 ℃. Rheological analysis reveals a progressive enhancement in polymer-asphalt interaction of TRPE modified asphalt (TRPEA) and mRPE modified asphalt (mRPEA), as evidenced by a reduction in rheological interaction index (h value) from 0.87 to 0.14. The results show that the Cole-Cole plots are insufficient to distinguish the compatibility of TRPEA and mRPEA under the specific test conditions. Due to the dissolution of large elastic particles, TRPEA and mRPEA exhibit a pronounced shift toward viscous behavior. Moreover, mRPEA shows improved deformation resistance at high temperature and highest fatigue life with 5.66×106 at 2.5% strain. Overall, this work provides valuable insights in optimizing waste-derived modifiers for sustainable pavement materials.]]></description>
      <pubDate>Thu, 09 Jul 2026 13:32:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2721197</guid>
    </item>
    <item>
      <title>Macro–Meso fracture behavior of high-RAP asphalt mixtures: Coupling fracture mechanics and crack path characteristics</title>
      <link>https://trid.trb.org/View/2720817</link>
      <description><![CDATA[Reclaimed asphalt pavement (RAP) is widely incorporated into recycled asphalt mixtures to improve resource utilization and reduce environmental impacts. However, the aged binder introduced at high RAP contents significantly compromises cracking resistance. This study investigates the macro–meso fracture behavior of high-RAP asphalt mixtures by coupling fracture mechanics parameters with crack-path characterization. Semi-circular bending (SCB) tests were conducted on AC-13, AC-16, and SMA-13 mixtures containing 30%, 40%, and 50% RAP at temperatures of −15℃, 0℃, and 25℃. Fracture energy, fracture toughness, cracking resistance index, and flexibility index were evaluated. An image segmentation approach was employed to identify crack propagation paths and quantify crack tortuosity and fractal dimension. The results indicate that increasing RAP content from 30% to 50% reduced fracture energy by up to 42% at −15℃ and caused a pronounced decline in crack tortuosity and fractal dimension. Temperature significantly influenced fracture behavior, with mixtures exhibiting brittle fracture at −15℃ and ductile fracture at 25℃. Among all gradation types, SMA-13 demonstrated the highest cracking resistance, maintaining a flexibility index of 6.92 at 50% RAP, which remained comparable to that of AC-16 mixtures at 30% RAP. Furthermore, crack tortuosity and fractal dimension decreased by approximately 12–15% and 6–9%, respectively, indicating progressively simplified crack propagation paths and reduced energy dissipation capacity. The results reveal a strong consistency between macroscopic fracture performance and mesoscale crack-path characteristics. Aggregate skeleton interlock promotes crack deflection and energy dissipation, thereby alleviating RAP-induced embrittlement and improving the fracture resistance of recycled asphalt mixtures.]]></description>
      <pubDate>Thu, 09 Jul 2026 13:32:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2720817</guid>
    </item>
    <item>
      <title>Life cycle assessment of asphalt rehabilitation for a private on-road circuit according to ISO 14040/44: A case study</title>
      <link>https://trid.trb.org/View/2704130</link>
      <description><![CDATA[The road construction industry is among the most resource and energy intensive sectors, exerting a significant environmental impact through the extensive use of raw materials, the generation of solid waste, and the emission of greenhouse gases. In recent years, increasing attention has been devoted to integrating Circular Economy (CE) principles into pavement engineering through the use of recycled materials and the reduction of energy consumption during production and construction processes. A comprehensive Life Cycle Assessment (LCA) and Life Cycle Cost (LCC) analysis is conducted for the asphalt rehabilitation and maintenance process carried out at a private on-road circuit. The present work presents a real-world implementation of a combined strategy involving Reclaimed Asphalt Pavement (RAP), Warm Mix Asphalt (WMA), and improved management practices. The strategy was applied in a high-performance on-road race environment. WMA containing 30% RAP was examined under two distinct management scenarios. The first scenario represents current industry practice, while the second incorporates targeted improvements in production site allocation, optimization of energy and fuel consumption, distribution of layers among regional plants, and transport logistics. The results show that, when assessed separately, management practices, the use of 30% RAP, and the adoption of WMA reduced Global Warming Potential (GWP) by 5–16%, 6–13%, and 2.5–13.4%, respectively. When combined, these strategies achieved up to a 25.3% reduction in GWP compared to the worst-case scenario. The results also showed that management measures alone, without additional investment or new technologies, not only provided environmental benefits and an approximate 5% decrease in asphalt production cost per ton but also created more favorable operational conditions for efficient recycling, leading to additional unforeseen environmental gains. These findings emphasize the importance of continued efforts to promote sustainability in asphalt pavements. Carefully integrated environmental strategies can achieve significant reductions in environmental impacts while enhancing economic performance. Such integrated strategies are effective and provide insights for sustainable road construction.]]></description>
      <pubDate>Tue, 30 Jun 2026 08:55:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/2704130</guid>
    </item>
    <item>
      <title>Advanced viscoelastic characterization of modified bitumen at low temperatures using 4-mm DSR testing</title>
      <link>https://trid.trb.org/View/2715549</link>
      <description><![CDATA[In this study, we combine low-temperature 4-mm DSR sweeps with (LVE) modeling to investigate broadening of the glass-transition region in multicomponent asphalt binders modified with crumb rubber (CR), SBS, and a (HV) additive. Two PG 64–22 base binders were tested as neat binders and as modified formulations containing CR (8 %), SBS (2 %), and HV (8 %) in different combinations after TFOT and PAV aging. Increasing modification level produced a progressively smoother and more gradual liquid-to-glassy transition, clearly expressed as broadening of the long-time relaxation spectrum. A central contribution of this work is extending the broadened power-law (BPL) relaxation spectrum approach to CR/SBS/HV-modified binders and demonstrating that the stretching parameter β serves as a quantitative indicator of long-time relaxation broadening. β increased from 0.16 (unmodified) to 0.56 (CR+SBS+HV), indicating the broadest and most gradual long-time tail of the relaxation spectrum in the most modified formulation. Time–temperature superposition was used to construct G* and δ master curves; among the evaluated models, the generalized sigmoidal form provided the most consistent description of both G* and δ. To build a consistent low-temperature assessment framework, β was interpreted alongside independent LVE descriptors near the glass transition, including smoother Booij–Palmen trends, progressively broader reduced G′ and G″ transitions, and wider δ(T) isochrone spans (ΔTδ). Apparent molecular-weight distributions derived from the δ-method further supported the activation of additional relaxation processes in modified binders. Overall, the integrated rheological framework provides screening metrics to identify binders with improved stress-relaxation capacity during cooling, thus critical for low-temperature durability.]]></description>
      <pubDate>Tue, 30 Jun 2026 08:55:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/2715549</guid>
    </item>
    <item>
      <title>Equivalent cohesive zone modeling of the bonding performance of slab track interface with bubble defects: Theory, validation, and application</title>
      <link>https://trid.trb.org/View/2715481</link>
      <description><![CDATA[Interfacial bonding performance is critical to the long-term service of CRTS III slab tracks. However, interlayer bubble defects will deteriorate interfacial bonding performance. To estimate the effects of the interlayer bubble defects on the track structure, an axial tensile finite element model (FEM) incorporating interlayer bubble defects is established. Via the use of this model, the effects of bubble defects on the interface are analyzed. A sensitivity analysis is subsequently conducted, and a mapping relationship is developed to determine the interfacial bonding parameters. Finally, a slab track FEM is developed to analyze the effects of bubble defects on the interface within the track structure, thereby simultaneously verifying the accuracy of the mapping relationship. The results reveal that interlayer bubble defects decrease the local bonding performance, with larger bubble defects posing a higher risk of interfacial damage than smaller ones do. Additionally, the overall bonding performance is approximately linearly negatively correlated with the interfacial porosity, whereas the effect of the individual bubble area is relatively limited. Furthermore, individual bubble area intervals are restructured according to the results of sensitivity analysis, and the equivalent FEM based on the mapping relationship is verified to be efficient and accurate. Additionally, while interlayer bubble defects alone do not alter the overall damage distribution under temperature gradient loading, they increase the risk of damage initiation. These findings provide theoretical guidance for engineering evaluations of interfacial performance.]]></description>
      <pubDate>Tue, 30 Jun 2026 08:55:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/2715481</guid>
    </item>
    <item>
      <title>Feasibility of using stabilized grouting wastes as a road foundation material</title>
      <link>https://trid.trb.org/View/2719050</link>
      <description><![CDATA[Cement-stabilized sand is widely used in road base construction, but its application is increasingly constrained by the shortage of natural sand. This study investigates the feasibility of reusing grouting waste (GW) as an alternative material in cement-stabilized road base mixtures. Seven GW samples collected from different sites in Belgium were characterized in terms of particle density, sand equivalent, methylene blue value, plasticity index, compaction behavior, mineralogical composition, and their 28-day unconfined compressive strength (UCS) was evaluated with cement contents of 4–12%. The results showed that the GW samples exhibited clear source-dependent variability, with lower particle density and sand equivalent, but higher methylene blue value and plasticity index than natural sand. Their optimum water contents ranged from 11.35% to 23.91%, indicating the need for source-specific moisture control. At 8% cement, the porosity of most cement-stabilized GW mixtures (29.9–36.9%, except GW F at 41.5%) was comparable to or lower than that of the cement-stabilized sand mixture (37.0%). The 28-day UCS of GW mixtures increased from 2.24 to 3.97 MPa at 4% cement to 5.01–9.33 MPa at 12% cement. With suitable cement dosage, all cement-stabilized GW mixtures satisfied the 28-day strength requirements of 4 MPa for road base materials in the Belgian specification, and some GW mixtures even developed higher UCS than the cement-stabilized natural-sand benchmark. The better-performing sources were associated with lower clay activity, favorable porosity, and possible residual cement-related contribution. A preliminary modified empirical framework was further proposed to describe the strength variation of cement-stabilized GW from different sources, increasing the overall correlation from R² = 0.6435 to R²= 0.8995. Overall, selected GW sources show preliminary laboratory-scale mechanical feasibility for road foundation applications, although durability, environmental compliance, and field validation remain necessary.]]></description>
      <pubDate>Tue, 30 Jun 2026 08:55:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/2719050</guid>
    </item>
    <item>
      <title>A Review of Interfacial Interaction Mechanisms of Steel Slag in Asphalt Concrete: Multi-Scale Characterization and Performance Implications</title>
      <link>https://trid.trb.org/View/2715688</link>
      <description><![CDATA[Steel slag, as a high-strength, alkaline, and rough-textured industrial solid waste, has been increasingly considered a sustainable alternative to natural aggregates in asphalt concrete. However, the hydration expansion risks induced by free calcium oxide and free magnesium oxide impose critical constraints on interfacial compatibility and long-term durability. This review systematically examines the interfacial interaction mechanisms between steel slag and asphalt from a multi-scale perspective. The physicochemical basis of compatibility is first analyzed based on the physical, chemical, and mineralogical characteristics of steel slag and the compositional and rheological properties of asphalt binders. Key interfacial mechanisms are then discussed, including physical adsorption, chemical bonding, formation and evolution of the interfacial transition zone, selective migration and redistribution of asphalt components, and the initiation and propagation of pores and microcracks. The capabilities and limitations of major characterization and simulation methods, such as SEM, AFM, X-CT, FT-IR, XPS, molecular dynamics, and discrete element modeling, are critically reviewed. Furthermore, the influence of interfacial bond strength, micromechanical heterogeneity, and structural stability on mechanical performance, moisture resistance, aging resistance, fatigue behavior, and durability is elucidated. Finally, existing research gaps are identified, particularly regarding long-term performance evaluation, in-situ characterization of interfacial evolution, multi-scale model coupling, and the lack of systematic life-cycle assessment and environmental benefit analysis. This review aims to provide a structured theoretical basis and practical reference for the interfacial design, performance optimization, and engineering application of steel slag asphalt concrete.]]></description>
      <pubDate>Tue, 30 Jun 2026 08:55:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/2715688</guid>
    </item>
    <item>
      <title>Performance assessment of sustainable cold asphalt mixtures with RAP and modified bitumen emulsion: a laboratory investigation of mechanical properties and moisture sensitivity</title>
      <link>https://trid.trb.org/View/2715667</link>
      <description><![CDATA[Recycled cold asphalt offers a sustainable and cost-efficient solution by incorporating reclaimed materials, reducing energy consumption, and minimizing environmental impacts. This study investigates the effectiveness of styrene-butadiene rubber (SBR) latex modification and varying reclaimed asphalt pavement (RAP) contents in enhancing the performance of cold recycled asphalt mixtures. The Modified Marshall method was used to prepare specimens with RAP contents (0, 25, 50, 75, and 100%) using both unmodified bitumen (UMB) and SBR-modified bitumen (SBRMB). Bitumen properties were evaluated through penetration, softening point, penetration index (PI), Fourier Transform Infrared Spectroscopy (FTIR), and surface free energy (SFE) tests. Mixture performance was assessed using Marshall stability (MS), indirect tensile strength (ITS), tensile strength ratio (TSR), resilient modulus (MR), resilient modulus ratio (RMR), and flow number (FN) tests. FTIR analysis revealed significant chemical changes in SBR-modified bitumen, including the formation of new polar bonds and enhanced intermolecular forces. The addition of SBR latex improved thermal stability by 18.5% and increased the PI from 0.41 to 2.28. SFE measurements showed a 16.2% increase in cohesion energy for polymer-modified mastics. Although increasing RAP content reduced MS by 24.2% at 100% RAP, SBR modification partially mitigated this decrease. ITS values improved by 15.2% with RAP addition, and moisture resistance indices (TSR and RMR) improved with both RAP and SBR incorporation. However, FN decreased significantly with increasing RAP content, with the highest RAP levels exhibiting a substantial reduction compared to the control sample. Statistical analysis using ANOVA demonstrated that mixture type was the most influential factor in determining performance, while the SBR modification effects were significant but less pronounced. The findings highlight the potential of combining SBR polymer and RAP to produce sustainable cold recycled asphalt mixtures.]]></description>
      <pubDate>Tue, 30 Jun 2026 08:55:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/2715667</guid>
    </item>
    <item>
      <title>Automated road surface condition monitoring–evaluation of pilot study</title>
      <link>https://trid.trb.org/View/2715341</link>
      <description><![CDATA[This paper evaluates the detection quality of an automated road surface condition monitoring system tested in a fully automated pilot study. The system integrates multiple image-processing modules, including a road damage detection model based on YOLOv8 and a road surface segmentation model using DeeplabV3. The system was deployed in an automated pilot study setup, from March 2024 to Sept 2024. To assess the system’s performance, a subjective evaluation of the model’s performance during pilot study was conducted with the help of road maintenance professionals using a five-point qualitative scale with categories "very poor", “poor”, “satisfactory”, “good” and "excellent". The results showed that 65% of the analysed images were rated as satisfactory or better for detection quality. In contrast, an F1-score of 0.45 was achieved by the YOLOv8 model during finetuning. The study also identifies key errors and limitations in the system’s automated detection, with a primary detection error identified as confusion between visually similar objects.]]></description>
      <pubDate>Tue, 30 Jun 2026 08:55:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/2715341</guid>
    </item>
    <item>
      <title>Constitutive modelling of recycled PET-modified asphalt concrete using CBM–PBM within a discrete element framework</title>
      <link>https://trid.trb.org/View/2715331</link>
      <description><![CDATA[Incorporating recycled polyethylene terephthalate (PET) into asphalt mixtures offers a sustainable approach to enhance pavement performance while reducing plastic waste. However, the mesoscale mechanisms governing the influence of PET on stiffness, deformation resistance, and fracture behavior remain unclear. In this study, a three-dimensional Discrete Element Method (DEM) framework was developed to investigate the constitutive response of PET-modified asphalt concrete through the explicit representation of aggregates, asphalt mortar, PET inclusions, and air voids. Two bonding schemes, the Contact Bond Model (CBM) and Parallel Bond Model (PBM), were implemented and compared in terms of stiffness, tensile strength, damage evolution, and crack propagation. The experimental dynamic modulus (|E*|), indirect tensile strength (ITS), resilient modulus (Mr), rutting, and moisture susceptibility tests were conducted for mixtures containing 0–10% PET by volume. The DEM microparameters were calibrated using |E*| and ITS data, whereas Mr, rut depth, and tensile strength ratio (TSR) were used for independent validation. The results show that PET incorporation increases the mixture stiffness, with the dynamic modulus rising from 3500 to 5159 MPa and improves the resilient response under repeated loading. ITS increased from 0.44 MPa for the control mixture to a peak value of 1.15 MPa at 6% PET before decreasing to 0.89 MPa at 10% PET due to interfacial weakening. The rut depth decreased consistently with increasing PET content, indicating enhanced resistance to permanent deformation, whereas the TSR values confirmed acceptable moisture durability. Mesoscale analyses revealed that PET modified the force-chain distribution and promoted interface-controlled damage at the PET–mortar contacts. Compared with CBM, PBM more accurately reproduces progressive stiffness degradation and distributed cracking. An optimum PET content of approximately 6% was identified, providing the best balance between stiffness enhancement, tensile resistance and durability. These findings provide mechanistic insights into PET-modified asphalt mixtures and support the development of performance-based sustainable pavement materials.]]></description>
      <pubDate>Tue, 30 Jun 2026 08:55:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/2715331</guid>
    </item>
    <item>
      <title>Thermo-mechanical interaction and time-dependent cracking risk assessment of early-age fly ash high-performance concrete</title>
      <link>https://trid.trb.org/View/2712891</link>
      <description><![CDATA[Fly ash (FA) is widely used in high-performance concrete (HPC) to mitigate hydration heat in massive bridge structures; however, its influence on early-age thermal cracking risk remains governed by the interaction between thermal stress and strength development rather than temperature reduction alone. This study investigates the effect of FA replacement on early-age thermo-mechanical behavior through adiabatic temperature rise (ATR) tests, strength development experiments, and numerical simulation of a representative 2.0 m × 3.0 m bridge pier cross section. Increasing FA replacement reduced the maximum adiabatic temperature rise from 58.1 °C to 47.9 °C, while delaying early-age tensile strength development. The ultimate hydration degree increased approximately linearly with FA content, indicating the need to adjust hydration models for HPC with high binder content. Thermo-mechanical analysis showed that mixtures with 0–20% FA maintained η < 1.0 during the first 7 days, whereas 30% FA exhibited a distinct cracking risk window between 39–68 h. Notably, the maximum cracking potential did not coincide with peak core temperature but occurred within a critical thermo-mechanical period of 42–65 h. The results demonstrate that early-age cracking risk is governed by the time-dependent stress-to-strength ratio rather than temperature magnitude alone. For the investigated structural dimensions and boundary conditions, FA replacement levels of 10–20% provide the most favorable balance between hydration heat reduction and mechanical performance.]]></description>
      <pubDate>Mon, 29 Jun 2026 09:20:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2712891</guid>
    </item>
    <item>
      <title>Sustainable resin-based fog seal materials replacing asphalt: Design of high penetrability, bond strength and aging resistance toward cleaner pavement maintenance</title>
      <link>https://trid.trb.org/View/2711248</link>
      <description><![CDATA[To promote the cleaner production and sustainable development of asphalt pavement maintenance, a resin-based fog seal material with high penetrability, bond strength and aging resistance was prepared in this study. The base resin was modified with a reactive diluent and three types of polysiloxane resins to reduce viscosity and optimize performance simultaneously. Through evaluations of penetrability, mechanical properties, and bonding performance, the suitable dosages of the monofunctional reactive diluent butyl glycidyl ether (BGE) and polysiloxane modifiers (MGS, PGS, and MPGS) were determined. The curing agent was modified by compounding a modified aliphatic amine with a polyether amine to further optimize workability. Nano carbon black was used as a light stabilizer to specifically enhance the material's aging resistance. The results indicated that a BGE dosage of 20% combined with 10% MPGS yielded a penetration depth exceeding 10 mm, demonstrating high penetrability. The optimal curing agent consisted of a 7:3 blend of modified aliphatic amine and polyether amine. Under this formula, the tack-free time was 2.25 h, the hard-dry time was 2.92 h, and the tensile fracture energy was 543 J/m³ . Furthermore, based on aging resistance tests and spectroscopic analysis, the optimal dosage of nano carbon black was determined to be 0.5%.]]></description>
      <pubDate>Mon, 29 Jun 2026 09:20:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2711248</guid>
    </item>
    <item>
      <title>Performance evaluation of asphalt mixtures and mastics containing precipitated calcium carbonate filler: Fatigue resistance at intermediate temperatures</title>
      <link>https://trid.trb.org/View/2710252</link>
      <description><![CDATA[Fatigue cracking remains a primary structural distress in asphalt pavements, necessitating the exploration of high-performance modifiers to enhance durability. This study investigates the multi-scale fatigue behavior of asphalt mixtures and mastics modified with Precipitated Calcium Carbonate (PCC) filler. A comprehensive experimental program was conducted, employing Indirect Tensile Fatigue (ITF) tests for mixtures and Linear Amplitude Sweep (LAS) tests for mastics at various PCC replacement levels (0%, 35%, 70%, and 100%) and temperatures (10 °C and 20 °C). To explore the potential underlying mechanisms, cohesive and adhesive bond strength tests were performed. Results indicate that the incorporation of PCC can extend the fatigue life of both asphalt mastics and mixtures while reducing their stress sensitivity. Phenomenological modeling suggests that increasing PCC content tends to optimize fatigue parameters at both scales; for instance, the fatigue slope (K2) of the mixtures shifted toward zero (e.g., from −1.252 to −1.014 at 10 °C), reflecting a trend toward enhanced structural robustness. Simultaneously, LAS test results revealed an improvement in mastic fatigue endurance across the replacement levels, with statistical validation via t-tests supporting the significance of these performance gains (p-value < 0.001). Mechanistically, strong second-order polynomial correlations (R2 > 0.96) were observed between cohesive/adhesive bond strengths and the fatigue endurance of both mastics and mixtures. The high specific surface area of PCC particles is thought to promote physicochemical interactions with the bitumen, potentially pinning micro-cracks and increasing the energy threshold for crack propagation. Notably, a strong correlation (R2 = 0.9572) was identified between mastic and mixture fatigue lives, suggesting that mastic-scale testing may serve as a valuable preliminary screening indicator for evaluating bulk mixture fatigue trends. This research suggests that PCC holds promise as a effective and sustainable modifier for potentially extending the service life of pavement structures.]]></description>
      <pubDate>Mon, 29 Jun 2026 09:20:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2710252</guid>
    </item>
    <item>
      <title>Laboratory and field performance of polymer-modified asphalt mixes with high RAP content in a pilot project</title>
      <link>https://trid.trb.org/View/2710250</link>
      <description><![CDATA[The interaction among polymers, aged binder from reclaimed asphalt pavement (RAP), and recycling agents (RA) is still a concern for the asphalt industry. Therefore, laboratory and field performance of six plant-produced polymer-modified (PM) mixes containing up to 40% RAP and RA included in a pilot project were evaluated in this study. The base binder performance grade (PG) specified for the control mix with no RAP/RA for this study was PG64–28M. A softer base binder (PG58–34M) was used for all other RAP mixes to reduce the need for RA dosage. In this study, the RA dosages for the RAP mixes were selected during the job mix formula (JMF) by restoring the high PG of the extracted binders containing RAP compared to the control mix. The extracted binder test results obtained during construction indicated that a softer binder might have been used for the control mix with no RAP instead of the specified PG64–28M binder. The laboratory AC mix results indicated a somewhat similar performance for the RAP mixes. The stiffer RAP mixes showed greater strain sensitivity in the flexural fatigue test than the softer mixes. The mainline mix with 23% RAP and no RA exhibited slightly lower fracture cracking resistance than other mixes. The mixes with RAP also showed higher rutting resistance in the laboratory than the control mix with no RAP. The comparison between the extracted binder and mix frequency sweep results indicated that both had similar rankings and trends, indicating good diffusion of the RAP and virgin binders, except for the mix with 40% RAP and RA. The field survey conducted after 34 months (2.8 years) of service indicated that all test sections (with and without RAP/RA) are in very good condition.]]></description>
      <pubDate>Mon, 29 Jun 2026 09:20:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2710250</guid>
    </item>
    <item>
      <title>Behavior of Transverse Cracks in Continuously Reinforced Concrete Pavement under Environmental Loadings</title>
      <link>https://trid.trb.org/View/2706530</link>
      <description><![CDATA[Continuously reinforced concrete pavement (CRCP) uses longitudinal steel to control transverse cracks, which form naturally to relieve tensile stresses induced by environmental loadings. Previous studies have suggested that such stress relief is highly localized, typically diminishing within approximately 300mm of a newly formed crack. This study investigates the strain interaction between adjacent cracks using a fully instrumented CRCP section on IH-20 in Sweetwater, Texas. Field measurements demonstrate that the formation of a new transverse crack significantly reduces longitudinal strain in both the steel and the surrounding concrete. Formation of a new crack reduced steel stresses around 24.8MPa at an existing crack 2.13m away. This finding provides direct evidence that stress redistribution can extend well beyond the traditionally assumed 300mm influence zone. Observations also indicate that cracks penetrating the full depth near the pavement edge may transition to partial-depth cracks toward the slab interior and remain stable over time. Adjacent transverse cracking significantly relieves vertical concrete stress at steel depth near an existing crack by approximately 0.67MPa. This represents roughly 20% of the concrete tensile strength, reducing the potential for horizontal delamination. Monitoring into the second winter season showed a mean crack width increase of about 0.1mm under comparable thermal conditions (t = 26.99, p < 0.001). This behavior contrasts with the commonly held assumption that stress diminishes progressively over time. Overall, these findings provide a refined understanding of transverse crack behavior in CRCP and support the advancement of mechanistic–empirical pavement performance models.]]></description>
      <pubDate>Mon, 29 Jun 2026 09:20:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2706530</guid>
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