<rss version="2.0" xmlns:atom="https://www.w3.org/2005/Atom">
  <channel>
    <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>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
    </image>
    <item>
      <title>Geo-Extreme 2025: Geotechnical Earthquake Engineering</title>
      <link>https://trid.trb.org/View/2694503</link>
      <description><![CDATA[This Geotechnical Special Publication contains 33 peer-reviewed papers on geotechnical earthquake engineering.  Topics include: soil dynamics and liquefaction; case studies; numerical modeling; ground motions and site response; and soil-structure interaction.  GSP 370 will be of interest to geotechnical engineers, climate scientists, insurance professionals, emergency managers, and policy makers working to address a wide variety of extreme events.]]></description>
      <pubDate>Wed, 22 Apr 2026 09:55:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2694503</guid>
    </item>
    <item>
      <title>Lessons Learned from Seismic Collapse Assessment of Buildings for Evaluation of Bridge Structures</title>
      <link>https://trid.trb.org/View/2263901</link>
      <description><![CDATA[Due to recent advancements in performance-based earthquake engineering methods, in modeling of complex nonlinear structural behavior, and in characterization of earthquake ground motions, it is becoming possible to directly simulate earthquake-induced structural collapse. These simulations can be used to develop probabilistic descriptions of structures' seismic collapse risk. This paper first summarizes recent developments in assessment of seismic collapse risks for building structures, which apply nonlinear time-history analyses to predict when structural collapse occurs. In the second part, the discussion focuses on how the lessons learned from these building collapse risk assessments can be applied to predicting the seismic collapse risk of bridge structures. The paper proposes extending current assessments of bridge seismic performance (which typically focus on prediction of structural damage prior to collapse) to include robust assessments seismic collapse safety. Key issues for structural collapse assessment relate to ground motion scaling and spectral shape, creation of nonlinear structural simulation models (differing in certain critical characteristics from models used to predict pre-collapse response), and incorporating uncertainties in ground motions and structural modeling.]]></description>
      <pubDate>Mon, 09 Feb 2026 08:39:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/2263901</guid>
    </item>
    <item>
      <title>Retrofitting the Bay Area Rapid Transit District Infrastructure for Earthquakes</title>
      <link>https://trid.trb.org/View/2263886</link>
      <description><![CDATA[It took more than 10 years for the San Francisco Bay Area to fully recover from the 1989 Loma Prieta earthquake, and many retrofit programs have been underway since then to seismically upgrade or replace critical infrastructure. The Bay Area Rapid Transit (BART) District is currently undertaking a major seismic retrofit program of its system and has several projects already under construction. In 2002, BART began seismic re-evaluations of its infrastructure. Using updated seismic criteria since the original design of the late 1960s / early 1970s, BART found that parts of its system were not as reliable as desired and developed a range of possible seismic upgrade options. Using a benefit-cost model, BART adopted a $1.3 billion seismic upgrade program. The cost of this program was approved by a two-thirds majority of voters in 2005 in a bond issue.]]></description>
      <pubDate>Mon, 09 Feb 2026 08:39:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/2263886</guid>
    </item>
    <item>
      <title>Upgrading a Lifeline for Seismic Safety through Performance-Based Earthquake Engineering—A Case Study at Anchorage International Airport</title>
      <link>https://trid.trb.org/View/2263884</link>
      <description><![CDATA[Anchorage International Airport is a critical component of Alaska's transportation system and its economy. Annually, over 4.5 million people use the Anchorage International Airport for air travel to other parts of Alaska, North America, and international destinations. Because of the distance between Alaska and the rest of the United States, and the sheer size of the state, air travel is one of the most popular and important means of transportation—a lifeline for Alaskans not living in close proximity to the Anchorage area. The importance of this facility, coupled with the region's high seismicity, makes seismic vulnerability an important factor of this lifeline's dependability. In 2002, Alaska's Department of Transportation (ADOT) commissioned a multi-disciplinary design team to evaluate the airport's 384,000 square-foot South Terminal, which supports domestic flights, for seismic vulnerability. The purpose of the seismic evaluation was to gain an overall understanding of the seismic deficiencies and to assess the risks associated with the facility, thereby allowing ADOT and the design team to collaboratively formulate a seismic risk reduction strategy. A major component of this risk reduction strategy was the implementation of a seismic upgrades project utilizing Performance-Based Earthquake Engineering (PBEE). This paper presents a PBEE case study of the Anchorage International Airport Seismic and Security Improvements Project, including evaluation findings, and rehabilitation design parameters and strategies for the South Terminal buildings that make up this important lifeline facility.]]></description>
      <pubDate>Mon, 09 Feb 2026 08:39:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/2263884</guid>
    </item>
    <item>
      <title>Seattle's Bridge Seismic Retrofit Program: Philosophy, Policies, and Criteria</title>
      <link>https://trid.trb.org/View/2263590</link>
      <description><![CDATA[This paper provides an overview of the Philosophy, Policies, and Criteria (PPC) along with how The Seattle Department of Transportation (SDOT) developed its seismic retrofit philosophy and established its policies upon which the criteria are based. The application of the PPC to one of the seven bridges, the Fauntleroy Expressway, will be demonstrated in this paper. The precast prestressed concrete "I" girder Fauntleroy Expressway was built in 1963 and consists of 25 spans ranging from 26 meters to 39 meters.]]></description>
      <pubDate>Mon, 02 Feb 2026 14:13:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2263590</guid>
    </item>
    <item>
      <title>TCLEE 2009: Lifeline Earthquake Engineering in a Multihazard Environment</title>
      <link>https://trid.trb.org/View/2663096</link>
      <description><![CDATA[This collection contains 141 peer-reviewed papers addressing topics related to the performance of lifeline systems during seismic events. Topics include: performance of specific lifeline facilities and systems, such as electric power, water and wastewater, land and air transportation, seaports, and gas and liquid fuel; analysis and engineering issues that apply across lifelines, such as seismic risk analysis, geotechnical earthquake engineering, lifeline interdependence, sustainable lifelines, and performance of various lifeline facilities subjected to blast, fire, volcano, tsunami and geohazards; lifeline risk management project and program planning, such as project funding issues and asset integrity management; special lifeline research programs, including those at the Pacific Earthquake Engineering Research Center (PEER) and the MCEER-Earthquake Engineering to Extreme Events (formerly Multidisciplinary Center for Earthquake Engineering Research); and performance of lifelines during major natural hazard events, such as Hurricane Katrina, Hayward Fault earthquake, and Wenchuan, China, earthquake.]]></description>
      <pubDate>Fri, 30 Jan 2026 09:03:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/2663096</guid>
    </item>
    <item>
      <title>Estimation of Liquefaction Induced Hazards in Küçükçekmece-Avcılar D100 Highway</title>
      <link>https://trid.trb.org/View/2563674</link>
      <description><![CDATA[The Küçükçekmece–Avcılar corridor of the D100 highway constitutes a critical component of Istanbul’s transportation infrastructure. Given its strategic importance, ensuring its operational continuity following the anticipated major Istanbul earthquake is imperative. The aim of this study was to investigate the liquefaction-induced geotechnical risks threatening the Küçükçekmece–Avcılar segment of the D100 highway. Initially, the study area’s liquefaction susceptibility was assessed through Liquefaction Potential Index mapping. Subsequently, post-liquefaction ground displacements were quantified using semi-empirical methodologies and advanced numerical analyses focused on representative critical sections. Numerical simulations incorporated various constitutive models for liquefiable soils, enabling a comparative assessment against semi-empirical estimations. The results revealed that semi-empirical approaches systematically overestimated the lateral displacements relative to numerical predictions. Moreover, the analyses highlighted the sensitivity of model outcomes to the selection of constitutive parameters, underscoring the necessity for careful calibration in modeling liquefiable layers. Despite considering the most conservative displacement values from numerical analyses, findings indicated that the D100 highway is likely to experience substantial damage, potentially leading to extended service disruptions following the projected seismic event.]]></description>
      <pubDate>Fri, 21 Nov 2025 08:44:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/2563674</guid>
    </item>
    <item>
      <title>Seismic Performance of Precast Steel-UHPC Composite Joints in High-Speed Railway Frame Piers</title>
      <link>https://trid.trb.org/View/2616156</link>
      <description><![CDATA[This study proposes a novel precast steel-ultrahigh-performance concrete (UHPC) composite joint for high-speed railway frame piers. Cyclic lateral loading tests were conducted on three 1:4.5 scaled specimens, each comprising a precast pier, a precast foundation, and a postcast joint. The influence of joint materials and the anchorage length of connecting rebars on seismic performance was investigated. All specimens exhibited flexural failure, characterized by concrete crushing in the pier and yielding of longitudinal rebars, while UHPC joints remained intact. Experimental results demonstrated that UHPC joints significantly improved ductility and energy dissipation while reducing residual deformation compared to normal-strength concrete (NSC) joints. The strain distribution of connecting rebars was analyzed, revealing a reduction in equivalent anchorage length from 17Dcr to 23Dcr in NSC joints to 8Dcr to 10Dcr in UHPC joints. Furthermore, the stress distribution factor was introduced, indicating that the upper studs in the steel-UHPC composite joints played a dominant role in load transfer. Displacement component analysis showed that UHPC increased the proportion of bending displacement, thereby delaying damage progression under extreme loading conditions. These findings underscore the potential of the proposed steel-UHPC composite joints for high-speed railway frame piers to enhance seismic resilience, improve structural integrity, and reduce maintenance requirements.]]></description>
      <pubDate>Wed, 19 Nov 2025 17:09:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2616156</guid>
    </item>
    <item>
      <title>Response of Seismically Isolated Bridges due to Property Modification in Friction Pendulum Bearings Arising from Environmental and Construction Irregularities</title>
      <link>https://trid.trb.org/View/2616153</link>
      <description><![CDATA[Friction pendulum bearings (FPBs) are widely employed in bridge design for seismic isolation. Water infiltration into FPBs has been documented in various cases, presenting a potential risk of ice contamination in cold environments. Both types of contamination may alter the seismic response of FPBs. Despite its practical relevance, there persisted a knowledge gap on the effects of water and ice contaminations on FPBs. To address this gap, experiments were previously conducted at the Earthquake Engineering Laboratory at University of Nevada, Reno, during which the responses of FPBs under water and ice contamination were evaluated relative to the clean, dry condition. The key findings from the experiments were that water contamination reduces the dynamic coefficient of friction in FPBs, and that single-surface sliding (SSS) occurs routinely under irregularities in loading and support conditions. SSS refers to sliding being engaged only on one surface of a double pendulum bearing. In this paper, to assess the implications of these phenomena on bridge seismic performance, analytical models are developed for multispan continuous RC box-girder bridges (hypothetical) and a steel I-girder bridge (representative of the Susitna River Bridge in Alaska) with both single and double pendulum bearings. Nonlinear time history analyses are performed for each bridge, considering various contamination scenarios. SSS is found to notably increase peak shear demands in the piers of the concrete box girder bridges, while water contamination modestly decreases these demands. The steel I-girder bridge is less sensitive than the RC box-girder bridges to the variations in bearing response. Additionally, this study establishes a correlation between relative isolator and pier force demands and the substructure-to-superstructure mass ratio. As the mass ratio approaches zero, pier shear force is very sensitive to variations in the isolator response, whereas as the mass ratio increases, the pier shear force becomes insensitive to variations in the isolator response.]]></description>
      <pubDate>Wed, 19 Nov 2025 17:09:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2616153</guid>
    </item>
    <item>
      <title>Pixel-level multicategory semantic segmentation of visible seismic damage in bridge piers using an Attention-Mamba Transformer-based U-Net model</title>
      <link>https://trid.trb.org/View/2611338</link>
      <description><![CDATA[Currently, many computer vision-based studies focus on cyclic test photos approximating structural behavior under seismic loads and struggling with severely imbalanced multiclass seismic damage detection, particularly cracks. This paper presents an approach for pixel-level detection of visible seismic damage in RC bridge piers, identifying cracks, spalling, reinforcement exposure, crushing, and buckling/failure. A semantic segmentation database is built from experimental images emphasizing real-time hybrid simulations, with lens correction, perspective adjustment, and augmentation to enhance diversity. Hypergeometric distribution and weighted loss functions address class imbalance at both sample and pixel levels. A self-attention-Mamba-driven transformer block with inception modules is integrated into a customized U-Net bottleneck, achieving per-class IoU over 0.7958. A VGG16 encoder with Mamba blocks further refines crack feature extraction (length, width, angles), reaching IoU above 0.6478. Overlapping and mirror padding improve mask blending. The model generalizes well to unseen bridge piers and shear walls, supporting accurate post-earthquake damage assessment.]]></description>
      <pubDate>Mon, 27 Oct 2025 13:57:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2611338</guid>
    </item>
    <item>
      <title>2.5D seismic analysis of undersea tunnels subjected to 3D arbitrary incident P- or SV-waves</title>
      <link>https://trid.trb.org/View/2611619</link>
      <description><![CDATA[A novel 2.5D framework is developed for seismic analysis of undersea tunnels subjected to arbitrarily incident 3D P- or SV-waves, a problem rarely treated previously in the literature. The formulation begins with the 2.5D equations of motion considering both 3D seawater–seabed and seabed–structure interactions. The 2.5D Equivalent seismic forces are then derived from the exact free-field seabed displacements regardless of critical angles. A complete analysis procedure with the hydrostatic pressures added is outlined to evaluate the tunnel's seismic behavior. The proposed method is validated against de Barros and Luco's solutions, as well as original seismic inputs. Finally, the 3D seismic response characteristics of the tunnel are investigated for two earthquake records. Key findings include: (1) Tunnel-lining responses are notably influenced by water depth under sub-critical P-waves and super-critical SV-waves. (2) Lining stresses exhibit greater sensitivity to vertical incident angles for large-angle P-waves and small-angle SV-waves in a 2D context. (3) As the horizontal incident angle increases, stress distributions on the lining become more uniform, with stress concentrations diminishing for both P- and SV-wave cases. (4) The most unfavorable condition for undersea-tunnel seismic design is the 3D super-critical incident SV-waves with large horizontal incident angles.]]></description>
      <pubDate>Mon, 27 Oct 2025 09:36:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/2611619</guid>
    </item>
    <item>
      <title>A novel damping adaptive pendulum isolation system for seismic resilience enhancement of continuous bridges</title>
      <link>https://trid.trb.org/View/2561116</link>
      <description><![CDATA[This study introduces a novel Damping Adaptive Pendulum Isolator (DAPI) designed to enhance the seismic resilience of continuous bridges subjected to near-fault excitations. The DAPI is characterized by its ability to accommodate thermal deformation under service loads while providing effective isolation during seismic events. An advanced numerical model of the DAPI is created using the OpenSees platform, and its accuracy is validated through experimental testing. The developed numerical model demonstrates reliable prediction of damping characteristics of the DAPI, including the energy dissipation per cycle and damping ratio. Friction characteristics of the DAPI are achieved based on experimental response data. The seismic performance of the DAPI system is evaluated through a series of case studies. Results show that the DAPI system significantly reduces peak girder displacement, though it also leads to increased permanent isolator displacement and seismic demand on bridge piers. To address this, Shape Memory Alloy (SMA) dampers are incorporated to enhance the recentering capacity of the DAPI system. The effectiveness of this combined system is further discussed, showing that SMA dampers effectively mitigate permanent isolator displacements with minimal impact on pier demands. Overall, this study confirms the feasibility and effectiveness of the proposed DAPI system, both independently and in combination with SMA dampers. These findings offer valuable insights and guidance for improving seismic resilience of continuous bridges.]]></description>
      <pubDate>Tue, 08 Jul 2025 09:56:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2561116</guid>
    </item>
    <item>
      <title>Seismic Vulnerability Analysis of Aqueducts Based on Probability Density Evolution Method</title>
      <link>https://trid.trb.org/View/2543172</link>
      <description><![CDATA[Aqueduct structures require high seismic performance, underscoring the critical importance of seismic vulnerability analysis. Previous studies have utilized traditional boundary methods, Copula methods, incremental dynamic analysis, or logarithmic normal cumulative distribution functions for vulnerability analysis. Currently, most existing research methods suffer from excessive computational complexity, limited flexibility, and reduced stability. To address these limitations, this study introduces a seismic vulnerability analysis approach for culvert structures that utilizes probability density evolution. The study performed a seismic vulnerability analysis on a three-span simply supported culvert structure, from the middle route of the South-to-North Water Diversion Project in China, and developed a fiber model using OpenSees finite element software for nonlinear time history response analysis. The research produced the vulnerability curve of the culvert structure, concluding that: 1) seismic vulnerability analysis based on probability density evolution effectively determines the structure’s failure probability and vulnerability curve; 2) failure probability distributions and trends vary for piers and supports under different seismic intensities, with supports failing more quickly; and 3) supports in culverts exhibit higher failure rates compared with piers under similar conditions, with probabilities of 6.528%, 28.346%, 35.203%, and 17.872% higher, depending on the type of pier with which it is being compared.]]></description>
      <pubDate>Thu, 24 Apr 2025 09:07:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2543172</guid>
    </item>
    <item>
      <title>A refined approach to identify and quantify structural damage consistent with requirements of earthquake design, assessment and inspection of RC bridge piers</title>
      <link>https://trid.trb.org/View/2525722</link>
      <description><![CDATA[During the 1980s, the quantification of structural damage gained impetus driven by the need to assess the overall performance of a structure under reversed cyclic random displacement loading like earthquakes. Further, as Performance-Based Earthquake Design (PBED) is getting widely accepted, it has become more evident that identifying and quantifying damage is the key step for ensuring the final desirable performance. But, there is a three-fold inadequacy present in the existing methods of estimating structural damage while simultaneously employing them in performance-based earthquake design, performance assessment and post-earthquake inspection. Several classical methods are available to quantify structural damage of flexure-governing members in terms of Damage Index (DI). However, these classical damage indices cannot clearly demarcate phenomenological damage states, such as cracking, yielding, spalling, buckling, crushing, and fracture, with the numeric DI values. To address this first inadequacy, some recent studies developed 3D-finite-element- and fibre-element-driven strain-based damage identification and quantification methods. Among these two, the major challenge of using 3D-finite-element-driven methods is that these are too computationally expensive for daily design practice. Being more computationally efficient, the fibre-element-driven damage estimation methods address the first inadequacy, but they also fall short while being simultaneously employed in all three contexts of design, assessment and inspection. Therefore, the present study develops a new concept called the Damage Envelope and a unifying damage estimation method that addresses all three inadequacies for flexure-governing (slender) members. The method does not presume the damage sequence, and yet it is computationally efficient compared to 3D-finite-element-driven strain-based methods. The method first identifies the sequence of different damage states being attained and then quantifies the severity of the overall damage; solid-section single-column slender RC bridge piers are considered to demonstrate this study. This method is applicable to all three types of nonlinear response history analyses: uni-directional, bi-directional and tri-directional.]]></description>
      <pubDate>Wed, 16 Apr 2025 11:26:28 GMT</pubDate>
      <guid>https://trid.trb.org/View/2525722</guid>
    </item>
    <item>
      <title>Seismic performance of an innovative two-level performance system: Self-centering reinforced concrete bridge pier with external inclined slack tendons</title>
      <link>https://trid.trb.org/View/2528734</link>
      <description><![CDATA[Self-centering reinforced concrete (SCRC) bridge piers are a type of bridge piers that return to their original position after lateral displacements during earthquakes, thereby enhancing post-earthquake functionality by minimizing residual displacements. However, their application has often been limited to regions with low seismic activity due to concerns about their reliability under severe earthquakes. This study introduces an innovative two-level seismic performance SCRC bridge pier (TP-SCRC) to address this concern and compares the seismic performance of the novel system with that of a conventional SCRC pier. A 1/3 scale SCRC bridge pier was initially modeled using OpenSees software and validated using available experimental data. Furthermore, a full-scale SCRC bridge pier with internal unbonded tendons and external dampers was designed using a displacement-based design method. To achieve two-level seismic behavior, external inclined slack tendons were added to both sides of the pier. Slack in the tendons is modeled with gaps at the ends, which prevent the tendons from engaging during low seismic events. Both SCRC and TP-SCRC full-scale bridge piers were modeled using OpenSees and subjected to quasi-static and seismic excitations. The seismic performance of both piers was evaluated using Incremental Dynamic Analysis (IDA) and fragility analysis, focusing on maximum and residual drift ratios. The results indicate that the proposed (TP-SCRC) pier exhibits superior seismic performance during severe earthquakes and significantly reduces the risk of bridge collapse.]]></description>
      <pubDate>Mon, 14 Apr 2025 17:08:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2528734</guid>
    </item>
  </channel>
</rss>