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    <title>Transport Research International Documentation (TRID)</title>
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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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    <item>
      <title>Improving Transportation Infrastructure Safety Through Flow and Scour Analysis at Porous Riverbank Protection Structures</title>
      <link>https://trid.trb.org/View/2695864</link>
      <description><![CDATA[Project Description: Protecting riverbanks from erosion during flood events is critical for ensuring the safety of transportation infrastructure located near rivers. Such erosion can undermine roadways and bridge foundations, leading to failures such as those observed on I-40 in North Carolina following Hurricane Helene. In locations where riverbank erosion poses a significant transportation asset risk, porous riverbank protection structures such as engineered logjams (ELJs) have been implemented as alternatives to traditional revetment approaches. The geometric design of ELJs deflects flow away from banks while their porosity reduces drag and toe scour, thereby limiting additional flood-related failure risks. Additionally, ELJs can be constructed incrementally using off-channel crane equipment, which reduces construction costs associated with channel diversion and dewatering. 

Improved tools are needed to predict how flow deflection and scour vary with ELJ porosity and internal structure. Advancing this knowledge will support more reliable ELJ design and reduce the risk of over- or under-design. A larger database of flow and scour depth measurements for ELJs with a range of porosities and characteristics is needed to improve scour prediction methods and provide flow validation data for two- and three-dimensional hydraulic models.

To address these research gaps, laboratory experiments will be conducted in a 32-foot-long open-channel flume to quantify flow and scour at porous bank protection structures. Model ELJs will be fabricated using 3D printing to have identical external geometry but systematic variation in porosity and pore configuration. Flow fields will be measured using UMKC’s particle image velocimetry (PIV) system that can measure turbulent flow fields around channel obstructions with high resolution (<1 mm vector resolution). These PIV measurements will be used to quantify flow deflection and shear stress amplification. In addition, clear-water scour experiments will document the maximum scour depth for each ELJ configuration. 
]]></description>
      <pubDate>Thu, 23 Apr 2026 17:50:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/2695864</guid>
    </item>
    <item>
      <title>Efficient probabilistic damage analysis of pile group foundations in long-span bridges subjected to ship impact</title>
      <link>https://trid.trb.org/View/2656382</link>
      <description><![CDATA[Ship-bridge collisions pose a growing threat to marine infrastructure, causing severe damage to vulnerable pile foundations and potentially triggering catastrophic bridge collapse. Although the ship collision response of sea-crossing bridges has received scholarly attention,most efforts have been devoted to analyzing the impact mechanics. Meanwhile, probabilistic fragility analysis, crucial for performance-based risk assessment, has been developed mainly for inland bridges under barge collisions. Therefore, a dedicated fragility assessment framework for sea-crossing bridges subjected to large-tonnage ship impact is still lacking. Compounding this, the computational expense of high-fidelity models makes large-sample fragility analysis impractical.This research has developed a computationally efficient fragility assessment framework, using curvature as the damage indicator. It combines the finite element model of fiber-reinforced beam units with an enhanced uniform design-assisted Gaussian process regression surrogate model to conduct reliable probabilistic evaluations and significantly reduce computational costs. Key uncertain parameters are sampled using the Augmented Uniform Design (AugUD) method to generate training data for a Gaussian Process Regression (GPR) surrogate model. The GPR surrogate model has extremely high prediction accuracy. In three different erosion depth scenarios, its R² value is all greater than 0.92. This model enables large-scale Monte Carlo simulations to evaluate damage probabilities under different collision conditions. Finally, a global Sobol sensitivity analysis identifies the most influential parameters governing the probabilistic damage outcomes.]]></description>
      <pubDate>Tue, 21 Apr 2026 14:30:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2656382</guid>
    </item>
    <item>
      <title>Extreme buffeting response of long-span bridges under probabilistic wind field: Environmental contours vs. brute-force Monte Carlo approaches</title>
      <link>https://trid.trb.org/View/2652502</link>
      <description><![CDATA[Turbulence parameters, which exhibit substantial uncertainty, are often disregarded in extreme buffeting evaluations. This study examines the long-term extreme buffeting response of a long-span bridge under a probabilistic wind field. First, the mean and turbulent wind field is analyzed to construct wind environmental contours. Then, a machine learning-based surrogate model using eXtreme Gradient Boosting (XGBoost) is employed to efficiently predict buffeting responses while reducing computational costs. Two strategies for computing long-term extreme buffeting responses are examined: (1) response evaluation along wind environmental contours and (2) direct estimation of annual extreme responses using Monte Carlo simulation (MCS) and the surrogate model. Results demonstrate that turbulence parameter uncertainty has a significant impact on the buffeting responses of the Xihoumen Bridge, with maximum torsional and vertical responses occurring under different wind conditions. Moreover, long-term extreme wind environment parameters do not always correspond to long-term extreme structural responses, underscoring the necessity of incorporating multiple turbulence parameters to accurately characterize wind-induced effects. The environmental contour method offers an effective hazard-oriented design strategy, and future work could explore the response-oriented design approaches that directly target structural performance.]]></description>
      <pubDate>Fri, 03 Apr 2026 12:12:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/2652502</guid>
    </item>
    <item>
      <title>A global framework for data-informed bridge examination</title>
      <link>https://trid.trb.org/View/2678120</link>
      <description><![CDATA[Examining the performance of an existing bridge requires information on several aspects, such as design choices, material properties, and ongoing degradation processes. It often happens that some critical information is not available. The traditional approach in structural engineering is to take the most conservative assumption for each unknown, following new-design principles. It will often be concluded that structural safety is not ensured and that the bridge must be strengthened or replaced. This conclusion has important economic costs, impacts on users, and environmental burden associated. In this paper, a global data-informed framework is proposed to examine structural safety of existing bridges accurately. Multiple state-of-the-art methodologies are unified to provide a comprehensive framework for bridge examination. Observations, which can include visual inspection, non-destructive testing, and structural sensing, enable the development of more realistic models of structural behaviour. A case study of a reinforced-concrete bridge in Switzerland illustrates the potential of the novel framework. Although almost no information was initially available on the bridge, the monitoring results show that it can be rationally concluded that the bridge is safe. This framework supports engineers in examining existing structures when crucial information is missing based on observations and engineering judgment.]]></description>
      <pubDate>Mon, 23 Mar 2026 08:34:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/2678120</guid>
    </item>
    <item>
      <title>Rapid Bridge Replacement of Concrete Rigid Frame Bridges</title>
      <link>https://trid.trb.org/View/2663288</link>
      <description><![CDATA[A rapid bridge replacement (RBR) method was designed and utilized for the replacement of five overpasses along Highway 417 at Rochester Street, Booth Street, Percy Street, Preston Street, and Bronson Avenue in Ottawa. The current paper focuses on the replacement of the overpass at Bronson Avenue which involved the replacement of two rigid frame structures, supporting eastbound and westbound lanes (EBL and WBL), separated by a 20 mm expansion joint gap.  The existing concrete rigid frame structures were demolished in place while preserving the existing footings, with excavation being performed in parallel. The new structures were prefabricated in staging areas near the sites and transported to their final locations using specialized heavy-lift equipment, including self-propelled modular transporters (SPMTs). The new rigid frames were founded on top of the existing footings.  Several replacement alternatives were studied, including staged construction, rapid bridge replacement with a composite steel girder deck, and the construction of a secant wall behind the footings during nightly closures. It was concluded that the engineering and construction costs for a rigid frame RBR alternative is the lowest cost among feasible alternatives and had the least impact on traffic.  A three-dimensional, linear elastic finite element analysis was conducted to ensure the strength and stability of the structures during lifting, transportation, and final backfilled service conditions. This presentation discusses the challenges encountered during the design and construction of the structure and the solutions implemented to address them. The construction was successfully completed in July 2023.]]></description>
      <pubDate>Thu, 12 Mar 2026 08:52:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/2663288</guid>
    </item>
    <item>
      <title>Fiber-Reinforced Polymer Decks for Bridge Rehabilitation: A Case Study</title>
      <link>https://trid.trb.org/View/2235291</link>
      <description><![CDATA[Fiber reinforced polymer (FRP) bridge decks are used in bridge rehabilitation projects, often because of their relatively low self weight and high durability. Related benefits of FRP include rapid construction and advantages in terms of life cycle costs (e.g., corrosion resistance). A case study bridge in Tippecanoe County is the first in Indiana to be rehabilitated with a FRP deck. Among the bridges evaluated, County Road 900E over Wildcat Creek is a three-span continuous steel stringer bridge with two concrete approach spans. The FRP deck replacement would only take place on the three main spans. This bridge rehabilitation project presents a unique challenge in that the deck would be widened with no changes to the superstructure. The resulting overhang would also be the longest seen for this application. Since the properties of FRP are such that serviceability issues govern deck design, requirements for the overhang dominate decisions related to deck type and geometry, and choice of barrier or guardrail. These and other project details will be discussed. The choice of deck is affected by deflection limits of the overhang at the exterior stringer. Based on American Association of State Highway and Transportation Officials (AASHTO) span-to-deflection ratio recommendations, a deck produced by hand lay-up rather than pultrusion is selected. The ability to tailor the deck cross section geometry to satisfy serviceability limits motivated this decision. The FRP deck consists of a honeycomb core sandwiched between two faces, or structural surfaces. This bridge design also involves a trade-off between a deeper section to satisfy deflection criteria and overall cost. Specifically, a deeper section will increase material cost for FRP and the cost of building up the concrete approaches to match the deck height on the main spans. The deck geometry also affects the decision regarding proposed stiffener brackets, which would supply discrete support points to the overhang at each diaphragm location. Finite element analyses show that the deck is significantly more flexible in its transverse direction, affecting distribution of load and resulting in absolutely no reduction in deflection or stress with the bracket supports. The brackets are therefore excluded from the design. Finally, the choice of vehicular rail/ barrier is also affected by the overhang. Both concrete barrier and steel guardrail options are evaluated. AASHTO allows for a reduction in overhang loading for concrete barriers due to the structural continuity provided to the deck. However, finite element analyses demonstrate that this provision is not applicable for this FRP deck application. This and dead load considerations result in the choice of a steel guardrail.]]></description>
      <pubDate>Tue, 10 Mar 2026 09:54:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/2235291</guid>
    </item>
    <item>
      <title>Bootstrap data envelopment analysis of the efficiency of LED and HPS lamps used in Malaysian public lighting</title>
      <link>https://trid.trb.org/View/2661772</link>
      <description><![CDATA[Road lighting is an essential component of urban infrastructure, contributing significantly to electricity consumption and operational costs in Malaysia. With growing emphasis on sustainable development, light-emitting diodes (LEDs) are increasingly promoted as energy-efficient alternatives to conventional high-pressure sodium (HPS) lamps. However, robust comparative evaluations of their performance in real-world installations remain limited. This study assesses the economic and operational efficiency of LED and HPS road lighting systems installed on Penang Bridge, Malaysia. Using bootstrap data envelopment analysis, which enhances the reliability of efficiency estimates by correcting for statistical bias, the study evaluates four key variables: installation cost, operation cost, energy consumption and lamp’s lifetime. The results demonstrate that LED lighting systems achieve higher combined economic and operational efficiency compared to HPS systems, primarily due to their longer lifespan and lower energy consumption, despite higher initial costs. These findings underscore the potential of LED technology to reduce electricity use and lifecycle costs, contributing to national energy-saving targets and sustainable infrastructure objectives. For policymakers and engineers, this research provides statistically robust evidence to support informed decisions on road lighting investments aligned with Malaysia’s National Energy Efficiency Action Plan and the United Nations Sustainable Development Goal 7 on affordable and clean energy. Future studies should incorporate lighting quality, spectral characteristics and full life cycle assessments to provide a more comprehensive evaluation of lighting technologies for road infrastructure.]]></description>
      <pubDate>Fri, 27 Feb 2026 11:00:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2661772</guid>
    </item>
    <item>
      <title>Performance of Benchmark Bridge Structures</title>
      <link>https://trid.trb.org/View/2234721</link>
      <description><![CDATA[Recent advances in performance-based earthquake engineering stemming from research by the Pacific Earthquake Engineering Research (PEER) Center have made critical assessment of highway bridge seismic vulnerability possible. Performance of the predominant types of reinforced concrete highway bridges is integral to the evaluation of transportation network performance under high-intensity earthquake scenarios. Additionally, probabilistic quantification of bridge response and vulnerability provides insight into the evaluation of current designs and proposed technologies at varying levels of seismic hazard and different site conditions. This paper illustrates the seismic vulnerability of two benchmark reinforced concrete bridge types, typical of new construction in California. Each bridge type has a variety of column designs for different seismic demands. A model of the structures is created that accounts for nonlinear behavior of the columns, deck, abutments, and expansion joints at the abutments. Seismic demand models are then developed using nonlinear time history analysis, including under near-field excitation. Damage in the bridge components is determined from experimental tests and component capacities. Finally, approximate repair costs are estimated from both discrete bridge-level damage states and the assembly of discrete component-level damage states using unit repair cost estimate data. The procedure for the testbed bridges is developed in a modular fashion to allow incorporation of emerging structural components, technologies, and analysis methods. The vulnerability of the base bridge types is presented in this paper as a benchmark with which to compare the use of enhanced performance structural elements, demands due to liquefaction and lateral spreading, and to observe system-level performance due to experimentally calibrated column, abutment, and foundation components from other PEER researchers. Examples are provided that illustrate the incorporation of alternate analysis methods and a fully coupled soil-structure system.]]></description>
      <pubDate>Fri, 20 Feb 2026 15:28:28 GMT</pubDate>
      <guid>https://trid.trb.org/View/2234721</guid>
    </item>
    <item>
      <title>FRP-Concrete Hybrid Composite Girder Systems: Web Shear Strength and Design Guide Development</title>
      <link>https://trid.trb.org/View/2666680</link>
      <description><![CDATA[The University of Maine developed a novel, fiber reinforced polymer (FRP) tub girder (referred to as a “CT girder”) for use in new bridge construction as an alternative to conventional steel and prestressed concrete structural members. CT girders have been identified as a promising technology to support sustainable and durable infrastructure development, as they are comparatively light and overcome many of the challenges associated with precast NEXT beam concrete structures by reducing shipping costs and camber variability caused by prestressing. Commercialization of this technology is underway, with the evaluation of the first CT girder bridge constructed for regular traffic, the Hampden Grist Mill Bridge (HGMB) completed (Davids and Schanck 2022), two more bridges to be completed this year, and other bridges in the design or pre-construction stage. To more fully characterize the CT girder’s behavior and to advance its acceptance and implementation in future bridge projects, two specific aspects of behavior and design must be addressed. First, a more complete picture of the CT girder system’s web material shear strength must be established by experimental testing. Second, uniform procedures and recommendations for design must be created and ultimately accepted as a design code. This final report consists of two primary sections. Section 2 details the experimental program run to better quantify web shear strength and puts the results of the tests in the context of CT bridge girders analysis and design. Section 3 contains the draft design guide. Included are results of 3D finite element (FE) simulations of web buckling in the form of easily used design nomographs.]]></description>
      <pubDate>Thu, 19 Feb 2026 17:04:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/2666680</guid>
    </item>
    <item>
      <title>Reconciling Urban Mobility and CCAM Digital Twins for Enhanced Integration and Mutual Advancement</title>
      <link>https://trid.trb.org/View/2652041</link>
      <description><![CDATA[Cooperative and Connected Automated Mobility (CCAM) is an emerging paradigm aimed at enhancing Urban Mobility (UM) through improved road maneuverability, reduced environmental impact, and better traffic flow. Despite its promise, CCAM is not yet fully integrated with the broader UM context. In parallel, Digital Twin (DT) technology has gained traction across sectors, including mobility, offering potential to bridge the gap between CCAM and UM. This paper first defines CCAM and UM as distinct domains, setting boundaries between them. It then proposes a detailed analysis and introduces an integrated conceptual model that combines both domains via a unified DT architecture. This model overlays the Urban Mobility DT stack—comprising services, models, and datasets—onto the CCAM-DT stack to highlight areas of synergy. Based on this model, the paper outlines a streamlined development process for DT architecture and defines the necessary technology components for implementation. Whether extending one DT stack into the other or merging both, the approach fosters interoperability and knowledge transfer. The study concludes by demonstrating how DT technology can be tailored to specific mobility domains to increase operational efficiency and lower costs. A proof-of-concept validates the model’s practical application, showing real-world potential for integrated, intelligent mobility systems.]]></description>
      <pubDate>Tue, 17 Feb 2026 10:30:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2652041</guid>
    </item>
    <item>
      <title>Seismic Risk Evaluation for the Baseline PEER Bridge Testbed</title>
      <link>https://trid.trb.org/View/2263854</link>
      <description><![CDATA[Post-earthquake repair costs and repair times are important for evaluating the performance of new bridge design options and existing bridges in preparation for the next major earthquake. Hazard and structural demand models describe the probabilistic structural response during earthquakes. Damage and decision models link the structural response to decisions on repair actions and costs. This paper proposes a step-by-step probabilistic methodology to evaluate repair metrics for different bridge components and the bridge as a system, corresponding to varying degrees of damage. Repair actions, quantities, times, and costs are input into spreadsheet templates, and a numerical tool evaluates the expected value and variance of both repair costs and repair times for a range of earthquake intensities. This methodology uses the concept of performance groups—groups defined to account for bridge components that are repaired together. Data can be customized for repair methods and bridge types particular to different regions.]]></description>
      <pubDate>Mon, 09 Feb 2026 08:39:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/2263854</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>Public Transportation Challenges for People with Mobility Impairments</title>
      <link>https://trid.trb.org/View/2562099</link>
      <description><![CDATA[This study systematically reviews barriers and accessibility challenges faced by prosthetic and wheelchair users in public transportation, adhering to PRISMA guidelines. A comprehensive analysis of 36 studies from 2014 to 2024 revealed significant challenges, including inadequate infrastructure, social discrimination, and technological limitations. Key findings highlight persistent issues such as inaccessible ramps, uneven sidewalks, discriminatory attitudes, and high costs associated with advanced assistive technologies. While innovations like microprocessor-controlled prosthetics and SmartWheels show promise, their adoption is hindered by usability and affordability concerns. Gender-based disparities and the role of socioeconomic factors were also identified, emphasizing the need for inclusive transportation policies and infrastructure. By synthesizing global perspectives, this review provides actionable insights for policymakers and transportation planners to enhance mobility and equity for users with disabilities. The findings advocate for targeted interventions, user-centered design, and broader implementation of innovative solutions to bridge gaps in transportation accessibility.]]></description>
      <pubDate>Tue, 27 Jan 2026 16:16:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/2562099</guid>
    </item>
    <item>
      <title>Fatigue Assessment of Bridge Members Based on In-Service Stresses-Interim Report No. 2: Data Acquisition System for Strain Measurements</title>
      <link>https://trid.trb.org/View/2635934</link>
      <description><![CDATA[When a bridge is designed, conservative assumptions are made with regard to load distribution and structural continuity. Simple support is assumed when rotational restraint exists, deck girders are assumed noncomposite when significant shear transfer occurs at service loads, haunch is ignored, and elements such as railing are treated as nonstructural dead load rather than as stiffening elements. As a result of these and other conservative assumptions, stresses calculated for design may be well above stresses computed on the basis of strains measured while the bridge is in service. The magnitude of the stress fluctuations under service load determines the fatigue life of the bridge. The accuracy of remaining fatigue life estimates can be improved if these estimates can be based on measured rather than computed strains, typically resulting in a significant increase in projected bridge life. A more accurate fatigue life estimate leads to fewer negative fatigue life computations for operating, undamaged bridges. The result is an overall reduction in retrofit and replacement costs. To take advantage of this cost savings, a data acquisition system has been constructed for use by the Oklahoma Department of Transportation in measuring strains on in-service bridges. Construction of the system involved the development of hardware and software to facilitate interaction with a general-purpose commercial datalogger. Application of the system requires the user to install strain gages on the structure of interest, extend leadwires from the gages to a junction box containing bridge completion circuitry, connect the junction box to a battery-powered datalogger, and connect the datalogger to an on-site computer. The computer is loaded with software to assist the user in setting up the datalogger and downloading collected data. This report contains information regarding construction of the data acquisition system which may be useful for system maintenance and operation. This report also contains a set of general guidelines for conducting a bridge test and applying the test results. It is recommended that a complete bridge evaluation include a thorough visual inspection, an analysis of the structure, and a load test. The load test should include both a series of short-term tests in which stresses are recorded as a truck of known weight passes over the bridge, and at least one long-term test in which the number and magnitude of stress cycles are recorded under normal traffic. Data collected using the data acquisition system can be used to estimate remaining fatigue life and set inspection intervals. The recommended procedure for estimating remaining fatigue life follows NCHRP Report 299, taking full advantage of the fact that stresses are measured rather than computed. The procedure for setting inspection intervals is based on a fracture mechanics estimate of the time required for a crack of an assumed initial length to grow to a critical length when driven by the measured stress cycles.]]></description>
      <pubDate>Tue, 20 Jan 2026 09:42:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/2635934</guid>
    </item>
    <item>
      <title>Enhancing Site Response Analysis for Bridge Infrastructure in the Southern Plains Region: Issues, Pitfalls, and Pathways to Improvement </title>
      <link>https://trid.trb.org/View/2646962</link>
      <description><![CDATA[Bridges in the Southern Plains Region are essential to the continuity and resilience of the regional transportation network. Although traditionally considered a region of moderate seismic hazard, past seismic events and updated hazard characterizations along with escalating bridge costs have highlighted the need for the additional use of site response analysis in seismic bridge design. This project aims to investigate and resolve key technical limitations in current site response analysis practices as applied to bridge infrastructure within the Southern Plains Region. These include discrepancies in design acceleration estimation between American Association of State Highway and Transportation Officials (AASHTO) general procedure and site-specific site response analyses, the influence of bedrock shear wave velocity on seismic hazard and amplification, the sensitivity of site response outcomes to input motion depth, and the comparative accuracy of equivalent-linear and nonlinear modeling approaches under varying site conditions. The project will utilize detailed geotechnical and seismic data from existing Southern Plains Transportation Center (SPTC), Arkansas Department of Transportation (ARDOT), and U.S. Geological Survey (USGS) efforts to assess representative bridge sites, ultimately producing evidence-based recommendations and tools for more reliable seismic design and evaluation of bridge systems throughout the Southern Plains Region.  

There are four objectives of this project. The first is to quantify discrepancies in fundamental period and design spectrum estimates between the AASHTO general procedure and site-specific site response analysis across varying geologic conditions. The second is to evaluate the sensitivity of site response predictions and Probabilistic Seismic Hazard Analysis results to different bedrock shear wave velocity assumptions, including stiff soil and rock layers. The third is to assess the influence of varying ground motion input depths—from shallow to deep—on spectral amplification and response characteristics for deep basin sites. The last is to compare equivalent-linear and fully nonlinear site response analyses to establish practical modeling guidelines based on site condition, shaking intensity, and data availability. Project tasks include (1) literature review, (2) site selection and data complication, (3) baseline site response analysis, (4) comparative and sensitivity analysis, (5) guideline development, (6) reporting, and (7) dissemination. ]]></description>
      <pubDate>Tue, 06 Jan 2026 17:14:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2646962</guid>
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