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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>
    <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>Research on automatic detection and analysis of concrete cracks based on deep convolutional neural network architecture</title>
      <link>https://trid.trb.org/View/2681421</link>
      <description><![CDATA[As the aging of concrete structures becomes increasingly severe, crack detection has become a crucial aspect of maintaining their sustainable use. This paper investigates an automatic detection and analysis method for concrete cracks based on deep convolutional neural network architecture. The study utilized drones equipped with high-definition cameras to capture images of concrete structures such as bridges and roads, collecting over 10,000 original images containing cracks. Using Labelme software for point-by-point image annotation and applying data augmentation techniques like rotation and scaling, the dataset was expanded to 30,000 images to meet the requirements of deep learning model training. An improved AlexNet model was developed, replacing the fully connected layer with global average pooling to enhance robustness and reduce overfitting. The model achieved an average accuracy of 95.42% on the test set, outperforming traditional methods by 15%. The model also proved effective in noisy environments. Additionally, a semantic segmentation model based on Fully Convolutional Network (FCN) was introduced, incorporating atrous convolution and spatial pyramid pooling, achieving a pixel-level accuracy of 97.6%, surpassing benchmark models such as FCN and U-Net. The model accurately estimated crack width, with an error rate within ±2% compared to field measurements. This method improves detection efficiency and accuracy while reducing manual intervention, providing strong support for the maintenance of concrete structures.]]></description>
      <pubDate>Mon, 13 Apr 2026 16:48:09 GMT</pubDate>
      <guid>https://trid.trb.org/View/2681421</guid>
    </item>
    <item>
      <title>Anchorage Design and Detailing for Fabric-Reinforced Cementitious Matrix Retrofits of Transportation Concrete Structures</title>
      <link>https://trid.trb.org/View/2691724</link>
      <description><![CDATA[The repair and rehabilitation of transportation structures is urgently needed to restore structural capacity, slow deterioration caused by aging, overloading, and environmental stressors, and minimize disruptions associated with large-scale replacement projects. State DOTs and the Federal Highway Administration (FHWA) have implemented several advanced rehabilitation techniques, including fiber-reinforced polymer (FRP) composites, ultra-high-performance concrete, and fiber-reinforced cementitious matrix (FRCM) systems. FRCM consists of an open-grid textile made of FRP or steel strands embedded within an inorganic cementitious matrix. The system offers multiple advantages over traditional FRP, including mechanical compatibility with concrete and masonry substrates, improved fire and elevated-temperature performance, vapor permeability, durability in moist or cold environments, and ease of application in field conditions.

As an externally bonded strengthening system, the performance of FRCM is governed by the ability of the FRCM–substrate interface to maintain composite action and to transfer forces effectively. Premature interfacial slip, end debonding, or localized interface damage are commonly reported for unanchored FRCM systems. These brittle failure modes often occur at loads far below the tensile capacity of the textile, limiting the effectiveness of the strengthening system to 30–60% of its potential and undermining both safety and return on investment. Introducing anchorage mechanisms into FRCM systems provides an engineered means to restrain interfacial slip, delay debonding, promote more favorable failure modes, and enable the textile to mobilize higher tensile strains. However, the existing literature on FRCM anchorage is sparse, fragmented, and lacking in unified, design-oriented guidance. Quantitative provisions addressing anchor geometry, capacity, and interaction with the primary FRCM reinforcement remain absent from current codes and standards.

The primary objective of this research is to advance the understanding, design, and implementation of anchorage systems for FRCM-strengthened concrete members, with the goal of mitigating premature debonding and achieving ductile, and efficient strengthening outcomes. Specifically, the project aims to: (a) synthesize and critically evaluate the current state of knowledge on FRCM anchorage; (b) develop and experimentally validate practical anchorage systems including transverse wraps, mechanical anchors, and spike anchors; and (c) produce a design-oriented framework for selecting, proportioning, and detailing anchorage systems.

Two coordinated experimental programs are proposed: (1) bond-level tests to characterize the effects of anchorage presence and type on joint force transfer, slip response, and failure mechanisms; and (2) flexural tests on reinforced concrete beams strengthened with anchored and unanchored FRCM reinforcement, to evaluate the translation of bond-level behavior to member-level performance and to verify design expressions under combined shear and normal stresses. The proposed research will equip state DOTs with validated anchorage solutions, support cost-effective preservation strategies, and accelerate the adoption of durable composite materials for extending the service life of transportation infrastructure.]]></description>
      <pubDate>Sun, 12 Apr 2026 23:52:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/2691724</guid>
    </item>
    <item>
      <title>Submergence of Floating Concrete Docks at Crescent City Harbor during the 2025 Kamchatka Tsunami</title>
      <link>https://trid.trb.org/View/2652062</link>
      <description><![CDATA[On July 29, 2025, an MW 8.8 Kamchatka earthquake generated a Pacific-wide teletsunami that produced energetic, long-period surges in Crescent City, California, with dominant harbor oscillations at periods of approximately 20, 25, and 40 min. Although water levels were moderate relative to previous tsunamis, currents in the inner boat basin were sufficiently strong to test the post-2011 marina rebuild. This paper documents a rare failure mode observed in situ: temporary submergence of large concrete floating dock modules at H Dock without structural breakup. We present tide-gage records, bathymetry, as-built information, and time-lapse video collected during the tsunami. During a flood surge, visually estimated current speeds of approximately 3.0–4.3 m/s (10–14 ft/s) impinged on H Dock, after which the deck lost freeboard and sank uniformly beneath the water surface. Frame-tracked kinematics indicated an approximately steady descent rate of 2.2 cm/s (0.85 in./s) following a brief approximately 1.3 cm/s2 (0.5 in./s2) acceleration; given the dock mass per unit length, the onset of submergence was consistent with a net downward force of roughly 44 N/m length of dock (3 lb/ft), implying that the flow just exceeded a critical threshold for submergence. The dock remained submerged for approximately 2 min and reemerged with sections misaligned. A mechanism consistent with observations was a negative lift induced by accelerated, constricted underdeck flow (i.e., the Venturi effect) that reduced pressure beneath the float and overcame the residual buoyancy of the float.]]></description>
      <pubDate>Thu, 02 Apr 2026 16:58:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2652062</guid>
    </item>
    <item>
      <title>Dynamic Response Analysis of Concrete Box Subgrade under Double-Line Heavy-Haul Railway</title>
      <link>https://trid.trb.org/View/2672665</link>
      <description><![CDATA[The concrete box subgrade, a novel structural form constructed from reinforced concrete to replace conventional fill subgrades, effectively addresses challenges associated with land scarcity and material shortages. A three-dimensional finite element model of the track-subgrade-foundation system was established via numerical simulation to assess the feasibility of the concrete box subgrade. Subsequently, a comparative analysis of dynamic stress, displacement, and acceleration were analysed under three operating conditions: bidirectional operation, unidirectional full load operation, and unidirectional empty load operation. The results reveal that, under moving train loads, dynamic stress is primarily concentrated within the active track zone. Along the vertical webs, dynamic stress initially increases before decreasing, peaking at 1.25 m (one-quarter of the vertical web depth) below the subgrade surface. At a depth of 3.0 m, the dynamic stress attenuation rate of the concrete box subgrade is 1.4 times that of the conventional subgrade, effectively mitigating stress transmission to the foundation. Under bidirectional operation, the maximum dynamic displacement of the concrete box subgrade is 0.203 mm, representing a 92.41% reduction compared to the conventional subgrade, demonstrating enhanced structural integrity and lateral deformation control. The maximum acceleration reaches 0.137 m.s-2, which is 78.86% lower than that of the conventional subgrade, indicating superior vibration mitigation. Copyright: © 2026 Liu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.]]></description>
      <pubDate>Mon, 23 Mar 2026 15:25:40 GMT</pubDate>
      <guid>https://trid.trb.org/View/2672665</guid>
    </item>
    <item>
      <title>Chloride transport in estuarine ship-lock concrete structure exposed to a unique seawater corrosive environment with low chlorine-salt concentrations and high-frequency drying‒wetting cycles: Experimental study and computational model</title>
      <link>https://trid.trb.org/View/2652441</link>
      <description><![CDATA[Estuarine ship-locks are the navigational structures closest to the sea, which can form a unique seawater corrosive environment characterized by low chlorine-salt concentrations and high-frequency drying‒wetting cycles. Such an environment is caused by the downstream saltwater tides infiltrating into the ship-lock chamber and coupled with the filling and drainage water processes during the ship-lock operation. This unique seawater corrosive environment can seriously threaten the durability of estuarine ship-locks concrete structures. Currently, the chloride transport mechanisms in concrete for estuarine ship-locks under such a unique seawater corrosive environment remain elusive. Particularly, the transport characteristics of chloride invasion into estuarine ship-lock concrete structures, driven by drying-wetting cycle environmental factors, necessitate further study. This paper investigates the effects of drying‒wetting cycle environmental factors of the unique seawater corrosive environment, including the environmental chloride salt concentration, the drying‒wetting frequency, and the drying‒wetting ratio, on the chloride transport in estuarine ship-lock concrete structure by carrying out a physical experimental study. Results indicated an "M"-shaped trend in chloride concentration, surface chloride concentration, and chloride diffusion coefficient of concrete with an increasing drying-wetting ratio. Additionally, the aforementioned chloride transport parameters exhibited a positive correlation with the increase of drying-wetting frequency and environmental chlorine-salt concentration. Notably, the environmental chlorine-salt concentration had the greatest influence on chloride transport, whereas the high-frequency drying-wetting cycles can diminish the promotion degree of environmental chlorine-salt concentration on chloride transport behaviors in concrete. Furthermore, the time-varying patterns of surface chloride concentration and apparent chloride diffusion coefficient in the estuarine ship-lock concrete structures, subjected to different drying-wetting ratios under low chlorine-salt concentrations and high-frequency drying‒wetting cycles, were quantified, and the mathematical relationship between the drying-wetting ratios and ship-lock structural elevation was derived. On the basis of Fick's second law, a computational model of chloride transport in estuarine ship-lock concrete structure was developed, incorporating the influence of structural elevation, i.e., drying-wetting ratios.]]></description>
      <pubDate>Mon, 02 Mar 2026 08:55:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/2652441</guid>
    </item>
    <item>
      <title>Smart Healing in Additively Manufactured Engineered Cementitious Composites Beams for Durable Transportation Infrastructure </title>
      <link>https://trid.trb.org/View/2665667</link>
      <description><![CDATA[This project investigates the self-healing capabilities of 3D-printed Engineered Cementitious Composites (ECC) for transportation infrastructure applications, focusing on enhancing the durability and longevity of 3D-printed concrete structures. In particular, the research will examine how factors such as material composition, fiber reinforcement, and curing mechanisms influence the self-healing behavior of 3D-printed ECC beams. This self-healing capability has significant potential benefits as the layer-by-layer deposition process used in 3D printing can introduce "cold joints" or interlayer weaknesses, which may negatively impact long-term durability. The project will explore whether ECC’s intrinsic self-healing ability can mitigate these effects and enhance the durability of printed infrastructure, such as pavements, bridges, and retaining walls, which are subjected to harsh environmental conditions. The specific objectives of the project are to: evaluate the influence of supplementary cementitious materials like fly ash and blast furnace slag on the self-healing properties of 3D-printed ECC; assess the effect of different fiber lengths (6 mm and 10 mm) on crack control and healing kinetics; investigate the impact of various curing regimes (e.g., water immersion, relative humidity conditions) on the healing process; and conduct mechanical testing, microstructural analysis, and data modeling to develop predictive models for self-healing behaviors. 

The research will produce implementable results in the form of optimized ECC formulations with enhanced self-healing properties for 3D-printed infrastructure. It will also generate valuable data, including mechanical performance metrics, microstructural insights, and predictive models that could shape future design practices and standards for 3D-printed construction. ]]></description>
      <pubDate>Wed, 04 Feb 2026 15:30:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/2665667</guid>
    </item>
    <item>
      <title>MDMCS: A Benchmark Data Set for Multidamage Monitoring of Concrete Structures</title>
      <link>https://trid.trb.org/View/2640248</link>
      <description><![CDATA[Concrete structures deteriorate over time due to environmental exposure and mechanical stress, leading to various types of damage such as cracking, spalling, corrosion, and exposed rebar. Automated detection using deep learning-based computer vision techniques is limited by the lack of high-quality, annotated data sets. To address this challenge, this paper presents multi-damage monitoring of concrete structures (MDMCS), a data set of 1,200 images with precise pixelwise annotations involving four types of damage (cracking, spalling, corrosion, and exposed rebar) and diverse lighting conditions and material textures. The data set was evaluated using six state-of-the-art segmentation models, validating the efficacy of the data set and providing benchmarks for damage detection models. MDMCS will facilitate advances in artificial intelligence-powered structural monitoring and robot-assisted automatic inspection for improving the operation and maintenance of concrete structures.]]></description>
      <pubDate>Thu, 29 Jan 2026 17:02:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2640248</guid>
    </item>
    <item>
      <title>Optimizing SEAHIVE® solutions to mitigate bridge scour (TXST)</title>
      <link>https://trid.trb.org/View/2662984</link>
      <description><![CDATA[Bridge scour remains the top cause for bridge failure in the United States. When scour is observed during bridge inspections, a plan of action must be established to ensure the safety of the traveling public. Bridge failure is obviously costly; scour mitigation and monitoring are additional costs for the life cycle of the structure. Scour is additionally challenging to predict and unforeseen changes in the hydraulic load (both in direction and in magnitude from extreme events) can further exacerbate bridge scour. This research is the next phase of Texas State University (TXST)'s effort to implement SEAHIVE® elements for scour mitigation. SEAHIVE® is an engineered protection system composed of concrete hexagonal prisms. Perforations on the side faces of the elements provide passage for water flow, dissipating the energy within the system while also adding structural complexity to improve its potential for habitat creation. SEAHIVE® is under research and development at the University of Miami (UM) for wave energy dissipation. TXST conducted experimental and computational studies on a horizontally stacked three-unit SEAHIVE® system. A three-unit system placed three pile diameters in front of a monopile reduced the scour magnitude by 70.2% and volume by 94.1%. The configuration also reduced tangential velocity by one-third and vertical velocity by 80%, effectively weakening vortex strength and minimizing local scour. A limitation of the first phase is the SEAHIVE® system was continuous in that it extended edge-to-edge across the TXST flume and in the computational model.
OBJECTIVE: The objective of this research is to expand the analysis to more realistically simulate field-scale challenges and to establish baseline design parameters towards testing a prototype system in the O.H. Hinsdale Wave Research Laboratory at Oregon State University (OSU). The calibrated coupled hydrodynamic-morphodynamic model in Open FOAM will be used for further analysis to include studying the effects of: soil density, flow height, velocity, and  SEAHIVE® length to pier diameter ratios. Additionally, in this phase we will analyze vertical SEAHIVE® systems, including a SEAHIVE® skirt around the monopile and a SEAHIVE® wall. Such data are needed more fully understand the practical boundaries of SEAHIVE®  as an effective green-gray scour counter measure and design the prototype scale experiments in the OSU flume.
]]></description>
      <pubDate>Thu, 29 Jan 2026 15:52:49 GMT</pubDate>
      <guid>https://trid.trb.org/View/2662984</guid>
    </item>
    <item>
      <title>Risk-Averse Seismic Rehabilitation Decision-Making for a Concrete Road Network</title>
      <link>https://trid.trb.org/View/2562083</link>
      <description><![CDATA[Seismic events can cause destructive effects on concrete road networks. Transportation agencies aim to mitigate the adverse effects of seismic events, focusing on enhancing resilience within resource constraints. However, existing seismic rehabilitation decision-making models do not consider decision-maker’s attitudes toward risk. This research focuses on developing a risk-averse rehabilitation decision-making model for identifying critical components of concrete infrastructure systems, considering deep uncertainties and decision-makers’ risk preferences, and designing an efficient optimization algorithm to solve the formulated problem. The methodology involves four steps: (1) calculate the probability of damage of each asset subject to seismic events; (2) Monte Carlo runs to model the stochastic nature of seismic damage; (3) traffic simulation to determine changes in network functionality; and (4) stochastic combinatorial optimization algorithm to determine the most critical concrete road network assets. Value at risk (VaR), a concept borrowed from quantitative finance, is employed to control the level of risk. The probability of damage for each concrete asset is calculated using empirical fragility curves. A multi-physics-based model was used to simulate the traffic model and seismic susceptibility of the concrete road network (CRN). The optimization problem is solved using a risk-averse simulated annealing approach to minimize the expected serviceability loss (ESL) within a controllable risk level. The model is applied to a typical road network in California. This developed research provides a foundational tool for infrastructure managers to optimize rehabilitation strategies, balancing the objective of maximizing network functionality within a controllable risk in seismically prone areas.]]></description>
      <pubDate>Tue, 27 Jan 2026 16:16:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/2562083</guid>
    </item>
    <item>
      <title>Life-Cycle Analysis of Proposed Performance-Based Specifications for Structural Concrete and Portland Cement Concrete Pavement in Georgia</title>
      <link>https://trid.trb.org/View/2622002</link>
      <description><![CDATA[Increasing adoption of performance-based specifications (PBS) rather than conventional prescriptive specifications for concrete mixes is a paradigm shift that is expected to increase the use of more innovative and durable materials. The adoption of PBS could result in meaningful changes to mix designs and qualification processes for concrete by state agencies [e.g., Departments of Transportation (DOTs)] and other owners, including allowing higher proportions of cement replacement, additional performance benchmarks, and shifting to site-specific designs. The shift in specifications could affect outcomes outside the performance specification, such as emissions and maintenance costs, over the life cycle of concrete-based infrastructure projects. These outcomes can be quantitatively evaluated to inform owners and producers during this transition. This paper examines proposed durability-focused PBS for concrete pavement and structural elements with a range of potential concrete mix designs for the Georgia Department of Transportation, using environmental life-cycle analysis and life-cycle cost analysis. Specifically, this analysis evaluates cradle-to-gate and cradle-to-grave environmental and cost impacts for both prescriptive and performance-based specifications over 30- and 40-year lifespans for concrete pavement and structural concrete applications. Concrete designed under the proposed PBS has projected lower lifetime climate impact relative to the existing prescriptive specifications, with a reduction in greenhouse gas emissions ranging from 11% to 13% (pavements) and 9% to 10% (columns). PBS adoption carries a modeled benefit–cost ratio of 1.3–1.7 (pavements) and 5.7–8.3 (columns). This analysis supports a recommendation that DOTs adopt such PBS for concrete mix design, largely due to expected reduced maintenance needs due to higher durability.]]></description>
      <pubDate>Mon, 26 Jan 2026 14:44:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/2622002</guid>
    </item>
    <item>
      <title>Bridging the gap between research and practice: the case of distributed fiber optic sensors for SHM of concrete structures</title>
      <link>https://trid.trb.org/View/2640594</link>
      <description><![CDATA[This paper shows the path followed by a research team at UPC-BarcelonaTech in order to implement the technology of distributed strain sensing using fiber optical sensors to structural concrete. To reach this objective it was necessary to bridge the existing huge gap between a monitoring technology developed in other fields to the specific case of civil engineering concrete structures. Therefore, bridging this gap was mandatory for a successful implementation of the new technology. This was achieved by a ‘3-span bridge’. How the 3 spans are defined, founded and built up is explained through the chapters of the paper by showing several laboratory and full-scale applications carried out in the last 15 years where thin-coated distributed fiber optical sensors (DFOS) and Rayleigh backscattering were the selected options for the distributed sensing. The process shown in the paper may have similar applications to other techniques born in other disciplines different from civil engineering, but that present clear potential applicability. After some adaptation developments because of the characteristics of the materials used in civil engineering structures, the research and testing at the laboratory level finally derives in a full developed methodology that is finally tested on some real-world prototypes.]]></description>
      <pubDate>Thu, 22 Jan 2026 09:10:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/2640594</guid>
    </item>
    <item>
      <title>A novel mechanical model for frost heave failure of concrete canal lining: Considering elastic boundaries</title>
      <link>https://trid.trb.org/View/2611657</link>
      <description><![CDATA[Frost heave failure of concrete canal linings in cold regions poses a significant threat to the safe operation of water conveyance systems. This study proposes a novel mechanical model for frost heave failure based on dual-parameter elastic foundation beam theory, incorporating the non-uniform deformation behavior commonly observed in engineering practice. The interaction between foundation soil frost heave and the lining is represented by a system of springs, with the lining boundaries modeled as elastic supports. Model accuracy is validated through comparison with field measurements and prior studies. Results show that the elastic boundary more accurately captures the deformation behavior near the top and foot of the lining. Compared with elastic boundaries, simply supported conditions result in 28.05 % greater peak displacement, 29.75 % higher peak bending moment, and 49.13 % lower shear force at the top of the lining. When elastic boundaries are included, negative bending moments emerge near the lining ends. As the vertical spring stiffness increases, the peak frost heave displacement initially decreases and then rises, while the extent of the negative bending moment regime contracts. A similar non-monotonic trend is observed for peak bending moment with increasing torsional spring stiffness, accompanied by expansion of the negative moment regions at the top and foot. When the torsional stiffness becomes excessively large, the absolute value of the negative moment exceeds that of the positive moment at the boundary, leading to a shift in the critical failure location. Increasing the lining thickness from 6 cm to 14 cm results in a 48.12 % reduction in peak frost heave displacement, with the location of maximum displacement shifting 15 cm toward the center of the lining.]]></description>
      <pubDate>Wed, 21 Jan 2026 15:36:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/2611657</guid>
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    <item>
      <title>Comparative Evaluation of Flexural Strengthening and Bond Performance of Reinforced-Concrete Beams Strengthened with Near-Surface-Mounted Titanium-Alloy Straight Bars</title>
      <link>https://trid.trb.org/View/2646168</link>
      <description><![CDATA[Strengthening reinforced-concrete (RC) members using near-surface-mounted (NSM) titanium-alloy bars (TiABs) has become an emerging method to extend the service life of RC structures. Current design and construction guidance for strengthening existing RC structures with this method is limited to the usage of TiAB with hooked ends, which can be challenging for structures where accommodating hooks is impractical. To evaluate an alternative mounting method, experimental work was performed in this study to investigate the flexural behavior of RC beams strengthened with NSM straight TiAB (without end hooks) and determine their bond strength for development length calculations. Five RC beams strengthened with NSM TiAB having TiAB bonded lengths were tested and compared against an unstrengthened control specimen. The test results indicate that beams strengthened with straight TiABs can achieve increased load capacity, provided that sufficient bond length is provided. Specimens with sufficient bond length demonstrated performance comparable to those strengthened with hooked TiABs, achieving yielding in both the steel reinforcement and the TiAB. An average bond strength of 0.5?ksi for straight TiABs is recommended when performing development length calculations. Additionally, this study presents guidelines and construction procedures for the practical application of NSM straight TiABs.]]></description>
      <pubDate>Tue, 30 Dec 2025 08:56:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2646168</guid>
    </item>
    <item>
      <title>Characterization of multi-waste concrete incorporating recycled aggregate, asphalt, fly ash, and rubber waste: Structural and environmental assessment</title>
      <link>https://trid.trb.org/View/2641873</link>
      <description><![CDATA[This study investigates sustainable concrete formulations incorporating recycled concrete aggregate (RCA), reclaimed asphalt pavement (RAP), crumb rubber (RR), and fly ash (FA), aiming to reduce environmental impact while maintaining structural performance. Nine mixes were experimentally evaluated for key physical (density, water absorption, sorptivity, porosity, ultrasonic pulse velocity) and mechanical properties (compressive and flexural strength, elastic modulus, Poisson’s ratio). Based on these results, two reinforced concrete buildings (3- and 8-story) were modeled and analyzed using nonlinear static (pushover) analysis. Life cycle impact assessments were carried out with SimaPro and Ecoinvent to quantify the environmental footprint of each case. Due to varying mechanical behavior, structural sections were resized accordingly, leading to different material demands and environmental outcomes. While all modified concretes showed reduced compressive strength (up to −56% vs. control), some achieved flexural strength increases (+27%) and improved ductility. A mix with 50% RCA, 25% RAP, and 20% FA required only a 2% increase in section size but yielded an average 20% reduction across environmental categories. In contrast, concretes with 50% RCA, 50% RAP, and 10% RR demanded between 5 and 10% larger sections and resulted in a 10% increase in environmental impact. This integrative, multiscale approach (i.e. experimental material testing, structural performance modeling, and environmental assessment) offers a robust and novel framework for developing low-impact concretes suitable for seismic design. However, further full-scale validation and long-term durability studies are necessary to confirm these findings and facilitate real-world implementation.]]></description>
      <pubDate>Mon, 29 Dec 2025 09:37:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2641873</guid>
    </item>
    <item>
      <title>Assessment of the Frost Damage Susceptibility of Highway Tunnels in Plateau Transition Regions: Example Taken from Gansu Province in Northwest China</title>
      <link>https://trid.trb.org/View/2601599</link>
      <description><![CDATA[Highway tunnels in cold regions are susceptible to frost damage. Assessment of the frost damage susceptibility of cold region tunnels (CRTs) is important for the planning, construction, and maintenance of tunnel projects. As a plateau transition region in northwest China and impacted by mountain permafrost and seasonally frozen ground, Gansu Province plays a vital role in the highway transportation network of China. In this study, firstly, the damage data of 116 highway tunnels were collected in Gansu Province based on an annual survey conducted in 2023. The statistical result shows that more than 82.8% and 66.4% of the surveyed tunnels have experienced cracks in the concrete lining and severe water leakage, respectively. The occurrence frequencies of icing on the concrete lining and pavement icing in the surveyed tunnels were 12.9% and 5.2%, respectively. Besides, 14 environmental factors of thermal environment, geotechnical characteristics, and hydrogeological conditions were selected to establish an assessment model on the frost damage susceptibility of CRTs. Based on the model, a frost damage susceptibility map of highway tunnels in the study region was created. The results show that the extreme low air temperatures contribute most to frost damage in mountain permafrost areas and some seasonally frozen ground areas with high mineralization of groundwater and freezing–thawing sensitivity of the surrounding rock. The model estimated that 14.4% and 62.2% of the study region had a high and medium frost damage susceptibility of tunnels. In regions with a low frost damage susceptibility of tunnels, the occurrence frequencies of icing on the concrete lining and pavement icing were 3.8% and 2.5%, respectively. As the frost damage susceptibility of tunnels increased, the occurrence frequencies of two types of damage increased to 33.3% and 22.2%. The damage investigation and assessment results will provide a reference for optimizing insulation design and frost damage prevention of CRTs.]]></description>
      <pubDate>Mon, 22 Dec 2025 16:07:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2601599</guid>
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