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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>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Mechanical Properties and Energy Evolution of Frozen Sodium Carbonate Clay under Uniaxial Compression Conditions</title>
      <link>https://trid.trb.org/View/2694595</link>
      <description><![CDATA[To investigate the mechanical properties and energy evolution of frozen sodium carbonate saline clay under different salt content and temperature, this study employed uniaxial compression tests combined with digital image correlation (DIC) technology. The results show that the uniaxial compressive strength (UCS) of frozen carbonate clay increases significantly with decreasing temperature, but exhibits nonlinear changes influenced by salt content. The failure modes of the soil samples are strongly influenced by salt content. At low salt contents, the failure is characterized by the development of cross-shaped shear bands, which can be attributed to the hardening behavior of the stress–strain curve and the enhanced ductility of the specimen. By contrast, at high salt contents, the failure is dominated by a single shear band, primarily associated with the softening response of the stress–strain curve and the increased brittleness of the specimen. The energy evolution analysis indicates that, as temperature decreases, both the total strain energy and dissipated energy of frozen sodium carbonate saline clay increase, reflecting the enhanced strength of frozen soil at lower temperatures. In contrast, both energies decrease with increasing salt content, showing a slight deviation from the trend of strength because strain energy depends on the combined effects of strength and stiffness. Based on dissipated energy evolution, an energy-based damage factor is introduced to characterize the progressive damage process, which exhibits a clear three-stage evolution comprising a quasi-undamaged stage, a slow damage accumulation stage, and a rapid damage development stage. The evolution of the damage factor shows good consistency with energy dissipation characteristics and DIC-observed strain localization. This provides a theoretical basis for assessing the mechanical properties of carbonate saline soils in cold regions.]]></description>
      <pubDate>Thu, 30 Jul 2026 10:07:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/2694595</guid>
    </item>
    <item>
      <title>Analysis of Temperature Field and Influence Factors in the Short Term of Filling of Heat Pipe–Thermal Insulation Berm Subgrade in Permafrost Area</title>
      <link>https://trid.trb.org/View/2701145</link>
      <description><![CDATA[To investigate the short-term variation patterns and influencing factors of the temperature field for composite roadbeds in permafrost regions, four finite-element models of roadbeds were established using COMSOL Multiphysics software, and numerical simulations and analyses were conducted, with the following results. The subgrade is filled in July and, in the first year of filling, the thermal effect causes the four kinds of subgrade freezing front to move down. The center of the heat-pipe subgrade has the highest soil temperature. The thawing process is significantly pronounced, showing an obvious shady–sunny slope effect, and the negative effect of the heat pipe is more obvious. Raising the height of the protection path has little effect on the temperature field in the center of the roadbed but it will cause the soil temperature of the sunny slope to rise, exacerbating the degree of thawing and making thermal thaw slumping more likely to occur. The higher the temperature of the subgrade filling, the higher will be the average temperature and the temperature peak of the underlying frozen soil in the subgrade; the temperature change at the center of the subgrade is more significant than that at the foot of the sunny slope. Therefore, in cold-region construction projects, the height of the insulation shield and the initial temperature of the filling material should be reasonably controlled to prevent more significant thawing of the underlying frozen soil in the short term.]]></description>
      <pubDate>Mon, 11 May 2026 12:24:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2701145</guid>
    </item>
    <item>
      <title>Macro-meso mechanical response of ice-bearing glaciofluvial deposits under thaw–freeze–thaw cycles</title>
      <link>https://trid.trb.org/View/2659888</link>
      <description><![CDATA[Glaciofluvial deposits are widespread in the southeastern Xizang Plateau, and their stability has been increasingly threatened by climate warming and tunnel construction, leading to frequent landslides and debris flows. To overcome the challenge of quantifying the highly variable mechanical behavior of ice-bearing glaciofluvial deposits under coupled effects of initial ice content, confining pressure, and thaw–freeze–thaw (TFT) cycling, this study conducted low-temperature triaxial tests and X-ray CT scanning on remolded specimens. The experimental dataset was used to analyze stage-dependent stress–strain responses and the evolution patterns of shear strength and strength parameters, and to elucidate the governing mesostructural degradation mechanism. The results indicate that the initial deposits exhibit strain-softening behavior that becomes more pronounced with increasing initial ice content and confining pressure; during TFT cycling, thawed specimens consistently show strain softening, whereas frozen specimens exhibit strain hardening. Peak strength shows a nonlinear dependence on initial ice content: it decreases monotonically with initial ice content in the thawed state but reaches a maximum at ∼10% initial ice content in the frozen state; correspondingly, the internal friction angle decreases and cohesion increases with initial ice content in the thawed state, while the frozen state displays a higher friction angle and markedly greater cohesion than the initial state. Both friction angle and cohesion deteriorate with increasing TFT cycles in thawed and frozen states and tend to stabilize after about six cycles. CT results reveal a periodic mesostructural evolution characterized by cementation fracture and structural recementation, which governs the observed mechanical transitions. Based on the experimental data, a quantitative modulus–shear strength relationship and a nonlinear coupled model incorporating initial ice content and TFT cycles were developed. Across all datasets, all fits exceeded R2 of 0.90 and kept NRMSE under 9% with a 6.42% mean, supporting engineering-oriented prediction of key mechanical parameters.]]></description>
      <pubDate>Wed, 29 Apr 2026 09:10:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2659888</guid>
    </item>
    <item>
      <title>Study on the influence of temperature field during thawing and sinking process of tropical undersea tunnel based on pipe curtain freezing method</title>
      <link>https://trid.trb.org/View/2652386</link>
      <description><![CDATA[With the rapid economic development of tropical coastal cities, undersea tunnels have become a crucial component of urban three-dimensional transport infrastructure. However, in addition to traditional construction challenges, tropical undersea tunnels also encounter significant risks related to freezing, thawing, and subsidence. The pipe curtain freezing method is the primary technique employed to address the issues of thawing and sinking of soft strata during the construction of tropical undersea tunnels. Inaccurate understanding of the variations in the thawing temperature field can result in rapid settlement during the thawing process, making the study of the thawing temperature field a critical issue. This study, set against the backdrop of the Sanya estuary channel project, employs both physical similarity tests and numerical simulations to validate findings mutually. It systematically elucidates the evolution of the forced thawing temperature field and the thawing behavior of permafrost using the pipe curtain freezing method. The results indicate that forced thawing significantly reduces the thawing cycle of the soil mass. Specifically, the temperature rise rate at monitoring points is faster the closer they are to the freezing tubes, followed by a brief phase change latent heat period; conversely, the further the distance from the tubes, the longer the phase change duration. The trends in temperature changes observed through both research methods during the thawing process are largely consistent, with temperature differences ranging from 1.5 °C to 2 °C, confirming the reliability of the numerical model. Furthermore, the thawing duration of the soil mass markedly decreases as the temperature of the circulating hot water increases. However, this effect becomes negligible when the circulating hot water temperature reaches 50 °Cor higher, indicating a threshold state between the thawing duration and water temperature increase, wherein thawing does not decrease linearly with temperature. The study establishes that there is an optimal thawing temperature for the pipe curtain freezing construction in tropical underwater tunnels, highlighting the importance of selecting an appropriate thawing temperature during actual construction processes.]]></description>
      <pubDate>Thu, 02 Apr 2026 16:58:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2652386</guid>
    </item>
    <item>
      <title>A DEM creep contact model with damage evolution for frozen soil</title>
      <link>https://trid.trb.org/View/2640872</link>
      <description><![CDATA[Frozen soil creep is a key factor in the settlement of cold region subgrades. Clarifying its macro and micromechanical deformation and damage mechanisms is essential for mitigating subgrade distress. To overcome the limitations of the existing creep contact model in PFC for accurately simulating the non-attenuating creep behavior of frozen soil, this study proposes a new discrete element creep contact model that incorporates damage evolution. By introducing a variable-stiffness damage element, the model effectively captures the third-stage creep behavior of frozen soil. Using the central difference method, the study derives the mechanical response equations for each stage of the contact model and compiles a dynamic link library (DLL) in C++ for direct use within the PFC3D software. A comprehensive description of the model development process is provided, and the contact model is validated using a double-sphere model, reproducing the non-attenuating creep curve and revealing the influence of new parameters on creep behavior. As a representative case, a series of triaxial creep tests on frozen subgrade soil under varying temperatures, confining pressures, and deviatoric stresses are conducted, leading to the establishment and calibration of a corresponding discrete element method (DEM) model. The results demonstrate that the model can accurately reproduce the creep mechanical properties of frozen soil across all stages under complex conditions. Furthermore, microscopic analysis of frozen soil reveals the evolution of particle displacement, damage development, internal structure, and pore distribution during different creep stages. The findings extend the application of DEM in studying the mechanical properties of frozen soil and provide a more precise contact model for DEM simulations of creep in frozen soil. It can be further applied to engineering-scale DEM studies of creep in cold region subgrades.]]></description>
      <pubDate>Tue, 17 Feb 2026 13:12:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/2640872</guid>
    </item>
    <item>
      <title>Thermo-Hydro-Gaseous-Chemical-Mechanical (T-H-G-C-M) coupled modeling on seasonally unsaturated frozen saline soil (SUFSS) as railway subgrade</title>
      <link>https://trid.trb.org/View/2636586</link>
      <description><![CDATA[The condensation and sublimation of vapor in seasonally unsaturated frozen saline soil (SUFSS) influence the water and salt distributions, thereby influencing the ice crystal growth, salt crystallization, and soil deformation. A Thermo-Hydro-Gaseous-Chemical-Mechanical (T-H-G-C-M) coupled model was derived in this paper to investigate the effect of condensation and sublimation of vapor in the freezing process of SUFSS. The discretization method was used to solve unknowns. The governing equations are discretized using COMSOL Multiphysics software. The presented model was applied to predict three laboratory model tests and a field monitoring data in literature. The well agreements between these results approved the accuracy of the proposed coupled model. The proposed coupled model could effectively consider the effects of condensation and sublimation of vapor in the pores, as well as the dissolution of dry air and salts in the liquid phase, on frost heave and salt expansion generated deformation of SUFSS.]]></description>
      <pubDate>Thu, 05 Feb 2026 09:16:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/2636586</guid>
    </item>
    <item>
      <title>Dynamic and Resilient Modulus of Frozen Soils</title>
      <link>https://trid.trb.org/View/2562009</link>
      <description><![CDATA[The dynamic and resilient modulus of frozen soils are pivotal parameters for assessing their mechanical properties under various loading conditions. This study characterizes the material properties of frozen soils, essential for transportation infrastructure, using modified AASHTO T 342 and 307 procedures. The dynamic modulus measures the soil’s ability to deform elastically under cyclic loading, while the resilient modulus reflects its capacity to recover from deformation. Influences such as freeze-thaw cycles, moisture content, and temperature play significant roles in these properties, with ice bonds in frozen soils breaking at different frequencies and temperatures, thus affecting mechanical behavior. This research modifies the Dynamic Modulus test procedure to determine the specific properties and behaviors of soil under low-temperature loads. Adjustments include utilizing different test equipment, sample preparation methods, and modifying test conditions (frequency, amplitude, and temperature) to replicate field conditions accurately. Comparative analyses were conducted using two moisture contents of sandy silt (ML), lean clay (CL), and fat clay (CH) to characterize the behavior of frost-susceptible subgrade soils. Understanding these moduli is crucial for designing and maintaining infrastructure in cold regions, ensuring the durability and safety of transportation networks. This knowledge enables better predictions of how frozen soils will respond under traffic loads, which is vital for engineering projects in challenging environments.]]></description>
      <pubDate>Tue, 27 Jan 2026 16:16:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2562009</guid>
    </item>
    <item>
      <title>Experimental investigation on the shakedown behaviors of embankment fill in cold regions</title>
      <link>https://trid.trb.org/View/2622319</link>
      <description><![CDATA[The shakedown behavior of embankment fill is key indicator for the stability evaluation of embankment. To investigate the shakedown behavior of embankment fill in cold regions, a series of cyclic triaxial tests were conducted by considering the effects of dynamic stress amplitude, confining pressure, cyclic stress path, temperature, and water content. The results show that the axial cumulative strain is mainly influenced by the dynamic stress amplitude and water content, while the resilient modulus is insignificantly sensitive to dynamic stress amplitude, confining pressure and cyclic stress path. The development characteristics of resilient modulus are distinctly dominated by temperature and water content. Subsequently, empirical models were proposed to predict axial cumulative strain and resilient modulus of frozen soil. Furthermore, three shakedown criteria were selected to assess cumulative deformation characteristics of embankment fill under various conditions of dynamic stress amplitude, confining pressure, cyclic stress path, temperature and water content. The classification for shakedown range is mainly affected by dynamic stress amplitude and water content. Finally, the applicability of each criterion was evaluated. The study can provide references for predicting long-term stability of embankment in cold regions.]]></description>
      <pubDate>Tue, 06 Jan 2026 09:17:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2622319</guid>
    </item>
    <item>
      <title>A stacking-based machine learning framework for predicting the unconfined compressive strength of frozen soil with missing data imputation</title>
      <link>https://trid.trb.org/View/2601815</link>
      <description><![CDATA[In cold-region engineering and artificial ground freezing applications, the unconfined compressive strength (UCS, σm) and failure strain (εf) of frozen soil are critical mechanical parameters for design and analysis. However, precisely predicting frozen soil mechanical behavior under complex conditions remains a significant challenge. This study compiled a dataset of 1,346 unconfined compression test records for frozen soils and addressed missing data via multivariate imputation by chained equations (MICE) utilizing a Random Forest (RF) algorithm. Leveraging Bayesian optimization (BO) and 10‐fold cross‐validation, we developed a stacked machine learning model combining three eXtreme Gradient Boosting (XGBoost) predictors for integrated classification and regression tasks. Compared to conventional empirical formulations, the proposed model demonstrates significant improvements in predictive accuracy for stress–strain curve types, σm, and εf. To enhance the model’s interpretability, we employed the SHAP (Shapley Additive Explanations) method to explain the impact of each feature on predictions. Furthermore, for scenarios with constrained data availability, two stacking models requiring fewer input features were constructed. Collectively, the stacking ensemble framework provides a robust and interpretable methodology for the accurate prediction of frozen soil mechanical properties under diverse and complex conditions.]]></description>
      <pubDate>Tue, 11 Nov 2025 09:23:09 GMT</pubDate>
      <guid>https://trid.trb.org/View/2601815</guid>
    </item>
    <item>
      <title>Determination of dynamic shear stress and strain thresholds in frozen coarse-grained materials: experimental and M-K statistical analysis</title>
      <link>https://trid.trb.org/View/2596768</link>
      <description><![CDATA[The dynamic features of frozen coarse-grained materials (FCGMs) are crucial for geotechnical engineering in cold regions. This study investigated the dynamic responses of FCGMs through stress-controlled triaxial cyclic tests. An improved Hardin model was proposed to describe stress–strain relationships. The variations in backbone curves, dynamic shear modulus, and damping ratio with various confining pressures, temperatures, and frequencies were investigated. Mathematical expressions were developed to describe the attenuation of dynamic shear modulus and the growth of damping ratio, considering the effects of temperature and loading frequency. The results indicated that both the dynamic shear stress and the maximum dynamic shear modulus increased significantly with decreasing temperature and increasing confining pressure. The Mann-Kendall (M-K) method was employed to identify the threshold dynamic shear stress and strain. It was found that the threshold dynamic shear stress increased with higher confining pressure and loading frequency, but decreased with rising temperature. When the shear modulus changes abruptly, the corresponding threshold dynamic shear strain of FCGMs is about 0.25%, where the dynamic shear modulus Gd is about 88% of the maximum dynamic shear modulus Gdmax. This study provides a new approach to determine the threshold dynamic shear stress and strain, reducing observation errors. Besides, this paper offers valuable insights into the dynamic characteristics of frozen soils in cold regions.]]></description>
      <pubDate>Tue, 28 Oct 2025 09:49:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2596768</guid>
    </item>
    <item>
      <title>Research on the mechanical behavior and modeling of artificially frozen clay under different unloading conditions</title>
      <link>https://trid.trb.org/View/2592339</link>
      <description><![CDATA[For the artificial ground freezing (AGF) method applied in urban underground engineering, the unloading effect is a crucial issue to be considered in the project design and construction. As the two typical unloading paths during tunnel excavation using AGF method, it is necessary to investigate the effects of the constant maximum principal stress (σ1) unloading path and constant mean stress (p) unloading path on the artificially frozen soil’s mechanical properties. This research aims to conduct experimental and theoretical investigations into the deformation and strength properties of artificially frozen clay. By setting different unloading methods, unloading ratios, and confining pressure variables, the deformation and strength development patterns of artificially frozen clay were explored. Experimental results indicate that the deformation resistance of artificially frozen clay increases with the decreasing unloading ratio. Furthermore, the deformation resistance of artificially frozen clay along the constant σ1 unloading path is generally superior to that along the constant p unloading path, with this difference being more pronounced under higher confining pressure conditions. During the unloading process, the constant p unloading path induces greater damage to the artificially frozen clay, disrupting the ice-cementation effect of the frozen sample, then leading to a lower shear strength compared to the constant σ1 unloading path. Besides, the energy dissipation of the artificially frozen samples observed in the experiments was analyzed, and correction factors for the two different unloading paths were proposed. Based on these correction factors, a stress–strain model considering unloading ratio and confining pressure was developed. The performance of the model was verified by predicting the stress–strain response of artificially frozen clay. The comparison results demonstrate that the experimental curves are in good agreement with the simulated responses of the proposed prediction model.]]></description>
      <pubDate>Thu, 16 Oct 2025 17:02:34 GMT</pubDate>
      <guid>https://trid.trb.org/View/2592339</guid>
    </item>
    <item>
      <title>Identification of joint probability distribution for thermal parameters of warm frozen clay with incomplete probability information</title>
      <link>https://trid.trb.org/View/2564438</link>
      <description><![CDATA[The thermal properties of warm frozen clay are easily affected by temperature factors, and the number of field measured data is limited. The thermal parameter distribution model constructed by ignoring the influence of temperature factors and small sample characteristic factors is not applicable to all situations. Therefore, this study studies the measured data of thermal parameters of warm frozen clay under different temperature conditions. Firstly, a binary frozen soil thermal parameter correlation structure characterization method is proposed based on Copula theory. Based on the measured data, the Bootstrap method is used to simulate the variability of small samples to determine the best fitting edge distribution and Copula function under different temperature conditions. Secondly, a joint probability distribution model is constructed based on the best fitting function. Finally, the fitting degree of the model is evaluated by the goodness of fit test. The results show that the distribution characteristics of thermal parameters of warm frozen clay under different temperatures are not consistent. The bivariate joint distribution model identified by the Bootstrap method can better characterize the correlation structure of thermal parameters]]></description>
      <pubDate>Wed, 16 Jul 2025 09:51:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2564438</guid>
    </item>
    <item>
      <title>Unified hardening (UH) model for saturated frozen soil incorporating creep behaviour</title>
      <link>https://trid.trb.org/View/2570054</link>
      <description><![CDATA[In this study, an elasto-viscoplastic constitutive model is proprosed to capture the creep behaviour of saturated frozen soil. The instantaneous normal compression line INCL and ageing time are employed to establish the relationship between the time-dependent effects of frozen soil and the change of over-consolidation state. By introducing a state parameter to integrate viscous and mechanical deformations, the isotropic elasto-viscoplastic constitutive model is established for saturated frozen soil. The solid-phase stress and time are adopted as the fundamental variables, and a time-dependent loading yield surface is derived to characterise the relationship between yield stress and time. The proposed model is extended into the 3D space of mean stress, deviatoric stress, and time variable. Two numerical studies are conducted to validate the proposed model in describing time-dependent behaviours, e.g the creep, relaxation, and the effects of loading rate under different over-consolidation states. The comparisons with experimental data from the literature demonstrate that the proposed model can reasonably describe the creep characteristics of saturated frozen soil.]]></description>
      <pubDate>Tue, 08 Jul 2025 09:56:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2570054</guid>
    </item>
    <item>
      <title>Dynamic mechanical characteristics and anti-thaw measures of warm frozen soil</title>
      <link>https://trid.trb.org/View/2558510</link>
      <description><![CDATA[Permafrost is widely distributed across the Qinghai-Tibet Plateau, and under the influence of climate warming, low-temperature frozen soil is gradually degrading into warm frozen soil. The ratio of ice to unfrozen water in warm frozen soil is highly sensitive to temperature changes, resulting in significant instability in its mechanical properties. To ensure the long-term stability of structures overlying permafrost foundations, conducting research on the mechanical characteristics of warm frozen soil and proposing effective measures to mitigate thaw settlement are crucial. This paper presents the research progress of the authors' team in the field of warm frozen soil dynamics. Using a dynamic triaxial apparatus for frozen soil and a self-developed dynamic direct shear apparatus, we investigated the behavior of warm frozen soil under different temperatures, revealing the influence of temperature on its dynamic stress-strain relationship and dynamic parameters. The development of frozen soil creep theory is reviewed, and advancements in frozen soil dynamics research are summarized and discussed. This paper proposes the use of solar refrigeration technology to protect permafrost, introducing a solar-powered compression refrigeration device and its working principles. The active cooling performance of the device was tested through model experiments and field trials. Additionally, the design and construction techniques of all-season cooling embankments are discussed, providing theoretical and technical support for the stability control of subgrade engineering in permafrost regions.]]></description>
      <pubDate>Fri, 20 Jun 2025 11:58:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/2558510</guid>
    </item>
    <item>
      <title>A multi-field coupled model contained volumetric strain for unsaturated frozen soil and thermal-hydro-mechanical evolution characteristics of permafrost tunnel</title>
      <link>https://trid.trb.org/View/2534410</link>
      <description><![CDATA[The entrance section of permafrost tunnels in cold regions is particularly vulnerable to frost damage caused by complex thermal-hydro-mechanical (THM) interactions in unsaturated frozen soils. The effects of temperature-dependent volumetric strain variations across different stratum materials on heat and moisture transport are often neglected in existing THM coupling models. In this study, a novel THM coupled model for unsaturated frozen soil integrating volumetric strain correction is proposed, which addresses bidirectional interactions between thermal-hydraulic processes and mechanical responses. The model was validated through laboratory experiments and subsequently applied to the analysis of the Yuximolegai Tunnel. The results indicate that distinct “layered” ice-water distribution patterns are formed in shallow permafrost under freeze-thaw cycles, driven by bidirectional freezing and water migration. Critical mechanical responses were observed, including a shift in maximum principal stress from the invert (1.40 MPa, frozen state) to the crown (5.76 MPa, thawed state), and periodic lining displacements (crown > invert > sidewalls). Frost damage risks are further quantified by the spatial-temporal zoning of ice-water content-sensitive regions. These findings advance unsaturated frozen soil modeling and provide theoretical guidance for frost-resistant tunnel design in cold regions.]]></description>
      <pubDate>Tue, 06 May 2025 09:11:49 GMT</pubDate>
      <guid>https://trid.trb.org/View/2534410</guid>
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