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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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    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>Correspondence Study of Three-Point Bending Strength Test and Semicircular Bending Strength Test Based on Crack Initiation Equivalent Strain Rate</title>
      <link>https://trid.trb.org/View/2709350</link>
      <description><![CDATA[To elucidate the correlation between crack initiation strengths obtained from different testing protocols, this study conducted three-point bending (TPB) and semicircular bending (SCB) tests on AC-13 modified asphalt mixtures under varying displacement rates. Digital image correlation technology was employed to monitor the real-time evolution of displacement and strain fields. Results indicate that the standard vertical displacement rate applied at the specimen top fails to align the two methods. Instead, the proposed “equivalent strain rate at the crack initiation point”—which integrates the time-dependent evolution of the internal stress-strain state—serves as a superior index for characterizing the relationship between TPB and SCB tests. Specifically, when this equivalent strain rate exceeds 0.006, the strength metrics derived from both testing methods demonstrate high consistency. Consequently, the SCB test shows significant potential as a reliable alternative to the traditional TPB method for evaluating the fracture performance of asphalt mixtures.]]></description>
      <pubDate>Wed, 26 Aug 2026 10:13:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/2709350</guid>
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    <item>
      <title>Investigating the Effect of Aging on the Fatigue Cracking Mechanisms of Modified Asphalt Concretes Based on Surface Free Energy Theory and Mechanical Tests</title>
      <link>https://trid.trb.org/View/2676388</link>
      <description><![CDATA[Fatigue cracking is a major distress in asphalt concrete, with aging identified as a key factor. This study investigated the effects of aging on bitumen–aggregate combinations by evaluating surface free energy (SFE) components of bitumen and aggregates, and calculating adhesion and cohesion energies. Also, the direct Pull-Off tensile test (in cohesive and adhesive failure modes) and indirect tensile fatigue (ITF) test were performed to assess the influence of aging and additives. To mitigate aging effects, ceramic fibers (CF) and granular hydroxy functionalized ultra-high-molecular-weight Polyethylene (FUHMWPE) were incorporated at 1.5% and 3% dosages. Results from SFE analysis were compared with Pull-Off and ITF outcomes to establish a clear relationship between adhesion/cohesion properties and fatigue life of mixtures. The SFE results indicated that aged bitumens, due to their lower non-polar component, form weaker non-polar (covalent) bonds with aggregates, which reduces the bitumen–aggregate adhesion free energy. Consistent with these findings, the pull-off test also showed that the mechanical adhesive strength of aged bitumens with aggregates is lower. The weakened bitumen–aggregate adhesion under aging conditions allowed micro-cracks caused by fatigue in the asphalt concretes to propagate along the bitumen–aggregate interface, thereby reducing the mixture's fatigue life. Furthermore, a decrease in ambient temperature within the intermediate service temperature range of pavements, combined with aging conditions, exacerbates the loss of mixture resistance against fatigue cracks occurring at the bitumen–aggregate interface. In contrast, CF significantly increased the cohesive and adhesive strength of the bitumen–aggregate system under aging conditions, improving the fatigue life of the asphalt concretes by an average of 22%. Similarly, the significant effect of FUHMWPE on enhancing bitumen–aggregate adhesion and cohesion led to an average 27% improvement in fatigue life. This indicates that FUHMWPE has a greater effect than CF on improving the intermediate-temperature properties of the asphalt concrete, owing to the polar functional groups in its polymer structure, possesses higher SFE. This promotes stronger polar interactions with aggregates, resulting in increased adhesive interfacial energy at the bitumen–aggregate boundary and, consequently, greater resistance to fatigue cracks. Statistical analysis results also confirm that both additives at a dosage of 1.5% significantly improve adhesion/cohesion-related properties and fatigue performance.]]></description>
      <pubDate>Tue, 24 Mar 2026 16:23:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2676388</guid>
    </item>
    <item>
      <title>Investigation of the Expansion Deformation Characteristic of Compacted Predisintegrated Shale</title>
      <link>https://trid.trb.org/View/2554159</link>
      <description><![CDATA[To investigate the expansion deformation of predisintegrated shale as subgrade soil and develop a calculation model to describe its expansion characteristic, the nonloaded and loaded expansion tests as well as expansion force tests were conducted on the typical predisintegrated shale under varying conditions. The results show that the expansion rate of compacted predisintegrated shale is greatly affected by initial water content, dry density, and overburden load, and that its expansion characteristics can be divided into three stages. After compaction, the expansion force of predisintegrated shale has a strong correlation with the initial dry density and initial water content, and 1.45 g·cm⁻³ can be used as threshold density for the rate of expansion force growth. Moreover, a comprehensive calculation model for the expansion rate and expansion force considering the coupling effects of various factors was proposed. This study proposes an alternative subgrade material using shale, which can efficiently save land resources and reduce engineering costs.]]></description>
      <pubDate>Fri, 20 Jun 2025 17:03:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2554159</guid>
    </item>
    <item>
      <title>Thermoplastic Rebar Durability Study</title>
      <link>https://trid.trb.org/View/2556688</link>
      <description><![CDATA[There is a need for non-corroding reinforcement of concrete. A significant shortcoming of commercially available thermoset pultruded rebar is that it cannot be field bent after initial fabrication, and common configurations such as hooked bars, stirrups and spirals must be created during the primary manufacturing process. This limits adaptability during construction and increases cost. A new thermoplastic composite pultrusion process has been implemented at the University of Maine (UMaine) Advanced Structures and Composites Center using a Continuous Forming Machine (CFM). The CFM has been fitted with dies to manufacture thermoplastic composite rebar with continuous fiber reinforcement for internal reinforcing of concrete. This thermoplastic composite rebar is also amenable to the creation of surface deformations using stamp forming and can be bent after manufacture. Surface modifications to the thermoplastic rebar can develop shear transfer capability through interfacial adhesion and interlocking with concrete comparable to steel rebar. A requirement for the adoption of the thermoplastic composite rebar is to have a database of material properties including strength and elastic modulus retention factors based on accelerated durability tests for simulated environmental conditions.]]></description>
      <pubDate>Wed, 02 Jul 2025 09:09:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/2556688</guid>
    </item>
    <item>
      <title>Evaluation of Rapid Mix Design for Lime Treated Materials</title>
      <link>https://trid.trb.org/View/2437690</link>
      <description><![CDATA[There is a need to develop guidelines for a rapid mix design with small samples for lime-treated materials for Texas Department of Transportation (TxDOT). Thus, the objectives of this project are to: (1) conduct a literature review and summarize state-of-the practice and key findings; (2) review and summarize mix design methods currently in use for lime treated materials; (3.) conduct a comprehensive lab program comparing existing procedures with small sample methods; (4) develop a lab mix design method for lime treatment that is similar in methodology, with accelerated methods of mix design currently in use or under development for asphalt-based and cement-based treatments; (5) demonstrate the procedures for upcoming construction projects; (6) develop recommended test procedures and updates to specifications. To achieve these objectives, the research team will conduct comprehensive testing and analysis program for a set of carefully selected soils and base course, with a range of plasticity index and clay minerals, and will develop a mix design procedure that will result in a significant reduction in turnaround time and amount of materials required for mix design. The research team will evaluate and compare physical, chemical, and mechanical test properties of the samples designed according to the current method and the selected potential methods, to recommend the most optimum curing, moisture conditioning and testing methods. The research team will provide conclusions and recommendations in the form of specification updates for effective implementation.]]></description>
      <pubDate>Thu, 03 Oct 2024 10:34:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/2437690</guid>
    </item>
    <item>
      <title>Full-scale model testing of a graded crushed stone sandwich structure within the ballastless track subgrade</title>
      <link>https://trid.trb.org/View/2404071</link>
      <description><![CDATA[This paper aims to analyse the static and dynamic characteristics of the sandwich structure consisted of an upper ballastless track structure layer, middle graded crushed stone interlayer, and lower foamed concrete subgrade layer, and clarifies its long-term dynamic stability. A full-scale test model of the sandwich structure being optimized was established, and then the static and dynamic loading tests were carried out. The results show that the use of foamed concrete as the subgrade filler can make the sandwich structure subgrade have better static stress and vibration diffusion effect compared with the traditional ballastless track subgrade. Under the loading conditions of this model test, the sandwich structure does not produce a resonance phenomenon when the loading frequency increases from 1 Hz to 10 Hz. And the sandwich structure has good vibration characteristics and long-term dynamic stability under cyclic loading. All these indicate that the graded crushed stone sandwich structure of the ballastless track foamed concrete subgrade can provide a smooth and long-term stable foundation for the line.]]></description>
      <pubDate>Thu, 22 Aug 2024 15:09:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/2404071</guid>
    </item>
    <item>
      <title>Mechanical performance of asphalt base layers with high RAP content and recycling agents</title>
      <link>https://trid.trb.org/View/2387199</link>
      <description><![CDATA[With circularity in mind, adding reclaimed asphalt in new asphalt mixtures is a common practice. While aiming for higher recycling rates, the need for better control of the mixture performance increases. Recycling agents are often proposed to restore the properties of aged binders. This study investigates the mechanical performance of plant-produced hot mix asphalt for base layers with high reclaimed asphalt content and recycling agents. Two field test tracks, each containing a section with and without a recycling agent, were constructed to allow for long-term performance evaluation. Plant-produced asphalt mixture from all sections was sampled and compacted in the laboratory and subjected to various mechanical tests, including rutting, stiffness, fatigue, cracking and water sensitivity. Besides a lower indirect tensile strength, the overall results indicate a limited influence of the used recycling agents on the mechanical performance of the mixtures, particularly in terms of resistance to rutting and fatigue cracking.]]></description>
      <pubDate>Tue, 18 Jun 2024 09:36:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2387199</guid>
    </item>
    <item>
      <title>Measurement and Evaluation Method for Power Plant Transfer Functions to Enhance Engine Sound Quality</title>
      <link>https://trid.trb.org/View/2359091</link>
      <description><![CDATA[The authors previously developed an intermediate evaluation index for transfer characteristics of the structural system of the completed vehicle to enhance the sound quality of combustion noise. Based on the results, a method was developed to obtain an index for the power unit similar to the above intermediate evaluation index by a shaker test on a stationary power plant. It was found that this shaker test and transfer characteristics evaluation method can approximately estimate the frequency band in which the structural system amplifies half-order components of the combustion noise related to sound-quality deterioration without conducting an actual engine operation test.]]></description>
      <pubDate>Tue, 30 Apr 2024 09:23:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2359091</guid>
    </item>
    <item>
      <title>Vertical Sediment of a Ballastless Track</title>
      <link>https://trid.trb.org/View/1972842</link>
      <description><![CDATA[At the Experimental ring of JSC “VNIIZHT” at Shcherbinka station, the comparative tests of four types of ballastless structures of the LVT track (Russian Railways, Russia), FFB (MaxBögl, Germany), NBT (Alstom. France), EBS (Tines, Poland) had been completed. The tonnage passed through the experimental section of four structures amounted to 600 million tons gross. The tests allowed confirming the operability of the ballastless track for the conditions of the Russian Railways, identifying the features of the current content of each of the structures and giving recommendations for their improvement. The paper analyzes the intensity of ballastless subsidence under the train load. Tests have shown that ballastless track can be used not only for a speed and a high-speed traffic, but also for combined and cargo traffic. Significant risks are that the ballastless track is more demanding for adhering to the construction technology, the composition of concrete mixtures and the quality of the preparation of the foundation.]]></description>
      <pubDate>Wed, 22 Nov 2023 12:47:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/1972842</guid>
    </item>
    <item>
      <title>Experimental Testing to Characterize Plastic Deformation, Dynamic Response, and Ductile Fracture of Inconel 718 Under Various Loading Conditions</title>
      <link>https://trid.trb.org/View/2255811</link>
      <description><![CDATA[A team consisting of Federal Aviation Administration (FAA) Propulsion Research Program, The Ohio State University (OSU), George Mason University (GMU), and the National Aeronautics and Space Administration Glenn Research Center (NASA-GRC) collaborated to develop a new material model in LS-DYNA for impact applications of Inconel 718, a nickel based superalloy used widely for turbine engine hot section blades, disks, cases, and other components. This report details mechanical testing of the plastic deformation and rupture of precipitate hardened Inconel 718. Specimens were tested in tension, compression, and shear under a wide range of strain rates from 10⁻⁴ s⁻¹ to 5000 s⁻¹ and temperatures from 23 °C to 800 °C. Experiments were conducted on five different plate stocks of thickness 1.27 mm, 2.03 mm, 3.17 mm, 6.35 mm, and 12.7 mm. Specimens were cut in different orientations to examine the directional dependence of the material. Dynamic tests were conducted using split Hopkinson bars. Full field strain measurements were made using digital image correlation (DIC) techniques. Ductile fracture was also examined for different stress states induced by subjecting various specimen geometries to different loading conditions. Fracture tests included tension experiments on notched plane stress, plane strain, and axisymmetric specimens as well as combined loading tension-torsion and compression-torsion experiments of tubular specimens and punch tests on flat specimens. The material test plan, experimental setups and procedures, specimen designs, and results are presented and discussed in detail. The Inconel 718 tested exhibits significant strain hardening and strain rate sensitivity as well as a general decrease in strength with increasing temperature.]]></description>
      <pubDate>Fri, 06 Oct 2023 13:40:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2255811</guid>
    </item>
    <item>
      <title>A mechanical equivalence similitude method for dynamic responses of high-speed train middle vehicles in a collision</title>
      <link>https://trid.trb.org/View/2213807</link>
      <description><![CDATA[Predicting the dynamic behavior of train collisions using similitude theory is a valuable design tool. However, several limitations and difficulties persist when designing a similar train model. This study proposes a mechanical equivalence similitude method when a train crashes into a rigid obstacle longitudinally, which can be used to establish similitude laws and predict the dynamic responses of a full-scale high-speed train middle vehicle. This method includes impact force equivalence (IFE) and finite-element stiffness equivalence (FESE). The aim is to overcome the insufficient accuracy of establishing a similar train model using traditional similitude methods. First, the similitude laws of the end energy absorber and the vehicle body were deduced. Subsequently, the 1/8th equivalent similar middle vehicle model of the high-speed train was established. The IFE method was employed to design a 1/8th equivalent similar model of the end energy absorber. Based on the FESE method, a 1/8th equivalent similar model of the middle vehicle body was built. Finally, the accuracy and effectiveness of a similar train model were validated through numerical simulations and tests. Comparing the results of the prototype, the errors of the dynamic responses were less than 4%, indicating that the mechanical response equivalence similitude method is effective for constructing a similar train model.]]></description>
      <pubDate>Mon, 25 Sep 2023 14:46:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2213807</guid>
    </item>
    <item>
      <title>SPR-4822:  Implementation Study for In-Place Testing of Asphalt-Treated Cold Recycled Pavements</title>
      <link>https://trid.trb.org/View/2253882</link>
      <description><![CDATA[This research will evaluate existing in-place mechanical test methods and provide guidance on the methods for use with cold recycled asphalt mixtures, specifically, FDR, CIR, and CCPR. The results of the selected test, or tests can then be used to make time critical decisions regarding final surface placement and traffic resumption on the recycled pavements. Additionally, the research will determine PEMD design inputs for FDR, CIR, and CCPR recycled pavements for use in designing such pavements.]]></description>
      <pubDate>Fri, 22 Sep 2023 10:20:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2253882</guid>
    </item>
    <item>
      <title>Comparative Evaluation of Surface Science Approach with Indirect Tensile Strength and Binder Bond Strength Tests to Determine Aggregate-Bitumen Bond</title>
      <link>https://trid.trb.org/View/2129349</link>
      <description><![CDATA[The present study investigated the efficacy of moisture sensitivity parameters obtained from the surface free energy (SFE) approach, namely the energy ratio (ER) and physiochemical parameters, by comparing the tensile strength ratio (TSR) and bond strength ratio (BSR) parameters, obtained from indirect tensile strength and binder bond strength tests, respectively. The bond strength against the moisture damage of basalt aggregates collected from two different sources with three different binder types, namely, unmodified (VG30), crumb rubber–modified (CRMB60), and polymer-modified (PMB40) binders, was evaluated. Results showed that both the ER parameter, which evaluates stripping potential of bitumen, and physiochemical parameters, which relate the compatibility of water with aggregate and bitumen, evaluated different rankings of an aggregate-bitumen system against moisture damage. However, the comparative study showed that physiochemical parameters evaluated similar rankings of aggregate and bitumen as obtained using TSR and BSR parameters in determining the aggregate-bitumen bond. Thus, it indicates that stripping of a binder may not always be the primary reason for moisture damage in bituminous mixes. It was observed that B2-CRMB60 with the highest ER of 0.71 was the least favorable combination in terms of resistance to moisture damage because of its lowest value of standard TSR and BSR parameters (i.e., 0.72 and 0.74, respectively) compared with five other combinations of aggregate-bitumen systems. Therefore, it is advised to carefully select the bond strength parameters to identify compatible aggregate-bitumen combinations while using the SFE approach. Further, it was found that the SFE approach is capable of addressing the complex moisture damage mechanisms in bituminous mixes; hence, it can be used for forensic investigations related to moisture damage in the field.]]></description>
      <pubDate>Tue, 25 Apr 2023 14:51:40 GMT</pubDate>
      <guid>https://trid.trb.org/View/2129349</guid>
    </item>
    <item>
      <title>Effects of Loading Rate and Temperature on Cracking Resistance Characteristics of Asphalt Mixtures Using Nonnotched Semicircular Bending Tests</title>
      <link>https://trid.trb.org/View/2127746</link>
      <description><![CDATA[In this study, the effects of loading rate and temperature on the cracking resistance of asphalt mixtures under static loading were examined by a nonnotched, semicircle bending test. Twenty-four test conditions combined by eight loading rates (0.1, 0.75, 3, 7.5, 15, 30, 50, and 80 mm/min) and three temperatures (−10°C, 0°C, and 15°C) were selected to be conducted using one stone matrix asphalt mixture. Five cracking parameters, namely, peak force (Fₘₐₓ), peak displacement (Dₚ), work of before-cracking (Wc), cracking failure displacement (Dcf), and work of cracking failure (Wcf), were proposed in order to evaluate the cracking resistance of asphalt mixtures. According to the results of this study, the cracking failure mode of asphalt mixtures can be divided into three conditions: brittle cracking, flexible damage, and fall in between. For the test condition of a higher loading rate and lower temperature, the cracking failure mode would be closer to brittle cracking. Both loading rate and temperature influence the test results of all cracking parameters in different ways. According to the statistical analysis, peak force is sensitive to loading rate, and the displacement and energy parameters are sensitive to temperature variation.]]></description>
      <pubDate>Mon, 24 Apr 2023 16:19:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2127746</guid>
    </item>
    <item>
      <title>Mechanical Characterization of Fine-Grained Lateritic Soils for Mechanistic-Empirical Flexible Pavement Design</title>
      <link>https://trid.trb.org/View/2127723</link>
      <description><![CDATA[Fine-grained lateritic soils, which are typically found in tropical regions and have been used successfully in low-cost pavements, are often considered inadequate for the base and subbase pavement layers when the material selection is based on the California bearing ratio (CBR). When analyzed in repeated load triaxial (RLT) test equipment, which is the most frequently used device to analyze the mechanical behavior of unbound pavement materials, fine-grained lateritic soils exhibit low levels of plastic deformation. Thus, to allow more appropriate analyses of the mechanical behavior of such soils compared to traditional CBR-based analyses, resilient modulus and permanent deformation tests using RLT test equipment were performed. Then, multifactorial regression analysis of the experimental results was performed to identify the parameters of the material models that are implemented in the Brazilian mechanistic-empirical pavement design software program, MEDINA. The experimental program included material characterization in accordance with the so-called miniature, compacted, tropical (MCT) methodology that is tailored specifically to classify tropical soils. For one of the lateritic soils, two key parameters, i.e., the stress level and compaction moisture content, were varied in the RLT permanent deformation tests. An additional numerical analysis using MEDINA was conducted to evaluate the structural characteristics of flexible pavements composed of the four lateritic soils analyzed in this study. In general, the results obtained from this study indicate that lateritic soils can potentially be used as base and subbase layers in flexible pavement structures.]]></description>
      <pubDate>Mon, 24 Apr 2023 16:19:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2127723</guid>
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