<?xml version="1.0" encoding="utf-8"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>TRB Publications Index</title><link>http://pubsindex.trb.org/</link><atom:link href="http://pubsindex.trb.org/common/TRIS Suite/feeds/rss.aspx?tc=NN%3APbp%2A" rel="self" type="application/rss+xml" /><description></description><language>en-us</language><copyright>Copyright © 2015. 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>TRB Publications Index</title><url>http://pubsindex.trb.org/Images/PageHeader-wTitle.png</url><link>http://pubsindex.trb.org/</link></image><item><title>Numerical Analysis of the Potential for Joint Separation in Round Concrete Culverts</title><link>http://pubsindex.trb.org/view/2701137</link><description><![CDATA[A common form of damage experienced by culverts is joint separation between culvert segments. Joint performance issues may allow water and soil to seep through the pipe leading to loss of soil support, which may ultimately result in roadway settlement or failure of the pipe. The factors that contribute to joint separation are unclear, and although past studies have investigated flexural demands across joints, no current studies are examining the axial tension demands that may develop across culvert joints. To this end, finite difference and finite element models of round concrete culverts were developed to examine the potential for separation from axial demands on culvert segments. The models investigated traffic loading, rise of the phreatic surface, freezing of the embankment, and dead load demands under the self-weight of the embankment. All of the above mechanisms led to axial tension along the length of the pipe. Of these, traffic loading caused the lowest separation forces, roughly 10% to 20% of the applied vertical load occurring under the roadway. Embankment self-weight caused built-in tensile demands under the driving surface. The rise of the phreatic surface and freezing of the embankment also caused significant separation forces, but near the embankment face. For untied pipe segments, increased depth to the culvert centerline and reduced embankment stiffness were the most critical parameters that increased the potential for joint separation. Further research focusing on detailed field observations to confirm the most likely locations of and conditions that lead to joint separation in culverts is recommended.]]></description><pubDate>Tue, 12 May 2026 16:57:36 GMT</pubDate><guid>http://pubsindex.trb.org/view/2701137</guid></item><item><title>Vertical Bearing Characteristic of Precast Hybrid Reinforcement Concrete Pipe Pile Considering Different End Forms in Stiff Silty Clays</title><link>http://pubsindex.trb.org/view/2701106</link><description><![CDATA[Precast prestressed reinforced concrete (PRC) pipe piles are increasingly adopted where static pressing is impractical; however, design-oriented evidence for their vertical bearing behavior in stiff silty clays remains limited. This study combines site static cone penetration tests with full-scale static load tests on hammer-driven PRC pipe piles with open-ended and closed-ended tips to clarify the governing load transfer mechanism and to improve capacity prediction for engineering design. The results show that pile tip configuration was a key factor influencing the bearing behavior of PRC pipe piles. Open-ended piles experience stronger driving-induced disturbance in the tested stiff clay layers, leading to lower mobilized shaft resistance than closed-ended piles. The responses of both pile types can be well described by a bilinear strain hardening load transfer relationship. Building on these observations, a three-stage load transfer function based on Rusch elastoplastic theory was developed and calibrated using test data, achieving improved ultimate bearing capacity prediction compared with conventional design parameter selection. For designs in stiff silty clay, median values of shaft resistance are recommended for open-ended piles; however, the upper-bound values of shaft and base resistances can be adopted for closed-ended piles. These recommendations should be applied cautiously beyond the tested pile configurations, soil properties, and installation method.]]></description><pubDate>Mon, 11 May 2026 14:37:18 GMT</pubDate><guid>http://pubsindex.trb.org/view/2701106</guid></item><item><title>Assessing the Structural Performance of Bolted Rail Joints Employing Various Fishplate Models via Finite Element Analysis</title><link>http://pubsindex.trb.org/view/2697861</link><description><![CDATA[In railway tracks, fishplates are attached to each side of two rail ends and secured with four bolts, providing what is known as a bolted rail joint (BRJ). This rail joint is involved in complex interactions between multiple components under wheel loads, leading to stress and deformation of each component, potentially resulting in failures of the railway track. In this study, the different roles of selected fishplate models in the structural performance of a BRJ under static load are investigated using finite element analysis with ABAQUS CAE. Three fishplate models are examined: a thin cross-section, a thick cross-section, and a modified design. The first two models are currently used in rail transportation, while the novel modified version is designed to enhance the structural performance of BRJs. Preliminary results indicate that using the modified fishplate significantly reduces stress on the upper rail fillet and fishplate. Additionally, vertical displacement in both the rail and fishplate is diminished. These improvements are expected to increase the service life and reliability of BRJs, thereby contributing to safer and more cost-effective railway operations.]]></description><pubDate>Sat, 02 May 2026 15:47:05 GMT</pubDate><guid>http://pubsindex.trb.org/view/2697861</guid></item><item><title>Analysis of the Effect of Shield Tunnel Construction Method Under Viaduct on Tunnel Structure and Pile Foundations</title><link>http://pubsindex.trb.org/view/2693760</link><description><![CDATA[To ensure the safe operation of elevated bridges during shield tunneling, this study investigates the west extension of Shijiazhuang Metro Line 1, where the tunnel passes beneath an existing elevated bridge. Field monitoring data serve as validation. A numerical model was developed using FLAC3D based on site-specific geological conditions to examine three schemes: (1) a 0.7 m clearance between the tunnel and pile foundation; (2) earth pressure balance shield (EPBS) cuts through the bridge foundation piles; and (3) pre-reinforcement of the surrounding soil using a U-shaped Metro Jet System around the cut pile. In Scheme 1, the pile exhibits longitudinal deformation aligned with the tunnel’s advance direction. Vertical deformation presents an S-shaped profile, and lateral displacement remains negligible. The most pronounced pile deformation occurs from 2.4 m behind to 0 m ahead of the pile. In Scheme 2, lateral deformation remains constrained, but vertical and longitudinal deformations increase markedly. Maximum surface settlement occurs directly above the pile, and the tunnel lining becomes elliptical. In Scheme 3, relative to Scheme 2, longitudinal and lateral pile deformations exhibit little change, while vertical pile deformation, surface settlement, and tunnel lining distortion are significantly reduced.]]></description><pubDate>Fri, 17 Apr 2026 08:57:14 GMT</pubDate><guid>http://pubsindex.trb.org/view/2693760</guid></item><item><title>Evaluation and Design of a Footing Hybrid Connection for Innovative Hollow-Core Fiber-Reinforced Polymer–Concrete–Steel Composite Columns</title><link>http://pubsindex.trb.org/view/2692377</link><description><![CDATA[To support the advancement of accelerated bridge construction in high-seismic regions, this study investigates a novel prefabricated column-to-footing connection designed for improved resiliency, constructability, and cost efficiency. The socket connection utilizes hollow-core fiber-reinforced polymer–concrete–steel (HC-FCS) columns with embedded corrugated steel pipes (CSPs). The composite HC-FCS column consists of a concrete shell sandwiched between an outer fiber-reinforced polymer tube and an inner steel tube. The inner steel tube is embedded into the footing connection of the HC-FCS column. The same authors tested the innovative socket connection on a large HC-FCS column under seismic loads, showing high ductility, strong moment and drift capacities, and promising potential for future design use. Building on previous experimental findings that demonstrated excellent seismic performance, this study employs finite element (FE) modeling in LS-DYNA software to conduct a parametric analysis of 50 large-scale column-to-footing connections. The FE models were used to critically assess the effect of seven parameters on the seismic behavior of such a novel column-to-footing connection. Consequently, design equations based on mechanical analysis of a simplified strut-and-tie model were proposed to determine the essential characteristics of the CSP in HC-FCS column-to-footing connections for practical implementation.]]></description><pubDate>Thu, 16 Apr 2026 09:24:32 GMT</pubDate><guid>http://pubsindex.trb.org/view/2692377</guid></item><item><title>Experiment and Numerical Investigation into the Direct Shear Performance of Bridge Column Joints Connected by Grouted Sleeves</title><link>http://pubsindex.trb.org/view/2691024</link><description><![CDATA[Grouted sleeves are extensively utilized in precast columns within the framework of accelerated bridge construction, with their components typically joined by splice joints. Experiment and numerical methods were adopted to investigate the shear performance of these splice joints connected by grouted sleeves. A series of three direct shear tests was conducted on sleeve connections under monotonic loading conditions. Furthermore, post-test analysis involved sectioning the specimens along the interface to examine the connection’s internal structure. The experiment findings confirmed that the shear strength was derived from a combination of cohesion, dowel action, and friction. Cohesion was observed to dissipate at the onset of displacement, after which the shear force increased progressively with lateral displacement. Additionally, the primary mode of connection damage was identified as the crushing of grout and the adjacent concrete around the steel reinforcement. Subsequently, finite element (FE) models were developed and validated against the direct shear tests with regard to failure modes and load-slip relationships. Utilizing these FE models, a parametric study was carried out to identify the key factors influencing the shear strength of the splice joints.]]></description><pubDate>Mon, 13 Apr 2026 08:41:21 GMT</pubDate><guid>http://pubsindex.trb.org/view/2691024</guid></item><item><title>Quantitative Patina Rating Index for Weathering Steel Bridge Girders</title><link>http://pubsindex.trb.org/view/2691023</link><description><![CDATA[Weathering steel is a low maintenance and cost-effective corrosion-resistant material that is widely used in bridge construction. The corrosion rate of weathering steel is known to be lower than carbon steel in a low- and medium-corrosive environment. This is because of the inherent corrosion resistance of the patina layer, which adheres to the substrate and protects the weathering steel from further corrosion. There are multiple guidelines to evaluate the protective performance of the rust layer that mainly emphasize visual inspection of the color and texture of the patina. However, these standards are, in general, qualitative and subject to observer bias. The tape adhesion test is one of the examinations proposed in the past that is less subjective, and it can be used to assess the functionality of patina to ensure the layer protects the underlying steel. The interpretation of the test results still relies on a partially qualitative judgment rather than a limited quantitative analysis. The objective of this research is to develop a reliable framework that can be used alongside visual inspections to increase accuracy in measurements. A Quantitative Patina Rating Index has been introduced in this paper, which was built on image analysis of 444 tape adhesion test samples, obtained from various macro and micro environmental conditions. The rating accounts for the size and the areal density of rust particles recorded on the tape samples and classifies patina in different categories. This classification will aid bridge owners and stakeholders in making more informed maintenance and inspection decisions.]]></description><pubDate>Mon, 13 Apr 2026 08:41:21 GMT</pubDate><guid>http://pubsindex.trb.org/view/2691023</guid></item><item><title>Study of On-Site Monitoring Analysis and Protective Measures for Long-Distance Parallel Excavation and Underlying Metro Tunnels</title><link>http://pubsindex.trb.org/view/2689787</link><description><![CDATA[With the acceleration of urbanization, the development and utilization of underground space have become increasingly common, leading to growing concerns about the impact of long-distance parallel excavation of deep foundation pits on underlying subway tunnels. This paper focuses on a foundation pit project where the parallel distance between the excavation area and the subway tunnel reached 270 m, using a combination of field monitoring and numerical simulation to analyze the deformation characteristics of subway tunnels during long-distance parallel excavation. The research results indicate that, with the increase in parallel distance, both vertical and horizontal displacements of the tunnel significantly increase. Furthermore, the “hardening soil” constitutive model achieved great simulation accuracy in modeling the deformation behavior of the soil surrounding the tunnel. Subway tunnel deformation control can be approached from three aspects: offsetting the additional stress load, improving the soil stiffness, and reducing the overall additional stress load. This study provides data support for further research on the impact of such extreme conditions on subway tunnels and offers a reference for designing and constructing similar engineering projects.]]></description><pubDate>Thu, 09 Apr 2026 09:01:27 GMT</pubDate><guid>http://pubsindex.trb.org/view/2689787</guid></item><item><title>Mechanism and Numerical Simulation of Drill Cuttings Transportation by Mud for Super-Long Bored Piles</title><link>http://pubsindex.trb.org/view/2684228</link><description><![CDATA[Drilling cuttings in super-long bored pile holes tend to accumulate at the base, potentially reducing the pile’s bearing capacity if not effectively removed. This study presents a theoretical analysis of the settling velocity of drilling cuttings and the return velocity of mud in super-long pile holes. In addition, it proposes a method for determining the upward return of drilling cuttings during the positive and reverse circulation hole cleaning. The effects of various drill pipe rpm, mud inlet velocities, particle diameters, mud densities, and mud viscosities on the cuttings carrying performance of mud were investigated using the Ansys Fluent fluid simulation software. The results indicated that as the mud viscosity increased, the sedimentation rate of the drilling cuttings decreased, leading to a more effective mud carrying effect. The mud density was adjusted dynamically based on actual working site conditions. Increasing the diameter of the drilling cuttings particles did not promote effective cuttings carrying by the mud. However, increasing the drill pipe rpm, mud inlet velocity, density, and viscosity could enhance the cuttings carrying effect. These findings provide valuable theoretical guidance for mud circulation hole cleaning in the construction of super-long bored piles.]]></description><pubDate>Thu, 26 Mar 2026 09:34:21 GMT</pubDate><guid>http://pubsindex.trb.org/view/2684228</guid></item><item><title>Biaxial Bending Response of Prestressed Concrete Girders Subjected to Accidental Asymmetric Prestressing Strand Loss</title><link>http://pubsindex.trb.org/view/2669695</link><description><![CDATA[Bridge prestressed concrete girders are vulnerable to sudden rupture of prestressing strands caused by accidental collisions with over-height trucks. These incidents often result in the asymmetric loss of prestressing strands and concrete sections, generating a biaxial bending moment caused by the combined effects of lateral bending and existing service loads. The induced lateral bending moment reduces the flexural resistance of prestressed concrete (PC) girders. However, the current AASHTO LRFD (load and resistance factor design) provisions for flexural resistance in PC members do not explicitly address the complexities introduced by biaxial bending, leaving the extent of strength reduction uncertain. This paper presents a series of 3-D nonlinear finite element (FE) models developed using LS-DYNA software. Four models were validated against full-scale experimental data. Force-deflection relationships were established, and the FE results were compared with predictions based on AASHTO LRFD provisions. This study concludes that lateral bending moments resulting from asymmetric losses of prestressing strands and concrete section reductions can reduce flexural resistance. The findings reveal that the AASHTO LRFD flexural resistance overestimates the residual flexural capacity of girders affected by biaxial bending by an average margin of 15%. To address this, an accidental lateral eccentricity reduction factor ΨIM of 0.85 is proposed for quickly incorporating the effects of biaxial bending in scenarios similar to those modeled in this study. The proposed factor is based on idealized FE simulations and is not intended for universal application to all impact damage cases. For real-world incidents, a case-specific assessment using refined analysis and diagnostics is recommended.]]></description><pubDate>Wed, 18 Feb 2026 16:27:48 GMT</pubDate><guid>http://pubsindex.trb.org/view/2669695</guid></item><item><title>Research on Damage and Failure Mechanisms and Seismic Vulnerability Analysis of Ribbed Arch Aqueduct Structures via Endurance Time Analysis</title><link>http://pubsindex.trb.org/view/2665688</link><description><![CDATA[In this paper, the Changgangpo aqueduct is taken as the research object to establish a three-dimensional nonlinear finite element model of the ribbed arch aqueduct structure. This study focuses on the dynamic response analysis, damage evolution rule, and failure mode of the ribbed arch aqueduct structure at different seismic intensities. The results indicate that the displacement response of the aqueduct structure increases steadily with the duration of seismic activity. In addition, when material damage characteristics are considered, the displacement failure response of the structure also increases gradually. During a 20 s seismic event, the peak curvature response of the arch foot, accounting for damage conditions, reaches 0.0167, which is 31.1% lower than the 0.0219 observed under linear elastic conditions. This reduction is primarily caused by damage to and failure of the concrete, which increases structural damping and absorbs significant energy, thereby reducing the effect of earthquakes on the structure and decreasing internal forces. The study also analyzes the damage evolution process and typical damage states of the aqueduct structure, including the trough body, ribbed column, and arch rib. Severe damage occurs mainly in the trough body, abdominal arch, midspan ribbed column, and arch foot of the upper pier. The failure mechanism of the bearing members, such as the lower abdomen arch, ribbed column, and arch rib, is revealed to be primarily shear failure and bending failure. In addition, a vulnerability curve of the aqueduct structure is constructed to estimate the failure probability under seismic loads. The research results reveal the seismically vulnerable parts and seismic performance of ribbed arch aqueduct structures, which can provide a theoretical basis for the seismic design and reinforcement of similar aqueduct structures.]]></description><pubDate>Mon, 09 Feb 2026 08:43:03 GMT</pubDate><guid>http://pubsindex.trb.org/view/2665688</guid></item><item><title>Performance of the Embedded Mechanically Stabilized Earth Abutment: A Case Study</title><link>http://pubsindex.trb.org/view/2655740</link><description><![CDATA[This paper evaluated the performance of embedded mechanically stabilized earth (MSE) abutments with geosynthetic reinforcement when subjected to seasonal temperature and rainfall cycles under working conditions based on an experimental project. The field monitoring data indicated that seasonal temperature and rainfall played an important role in the in-service performance of the abutment. Compared with conventional MSE abutments, the embedded bridge substructure (pile) led to significant temperature differences within the abutment, especially in seasons with continuous temperature changes, forming two distinct temperature distribution patterns. The vertical distribution of the lateral facing deformation underwent a transition from a uniform pattern to a midbulging pattern, which was accelerated during increasing temperature and rainy seasons. The interaction between the embedded pile and reinforced soil behaved as a localized constraint effect and led to a limitation on the bulging phenomenon. The piles also restricted the short-term variations in earth pressure induced by both temperature and rainfall, particularly on the cross-section intersecting the pile. The lateral earth pressure behind the facing was coordinated with its lateral deformation. With the development of lateral facing deformation, lateral earth pressure behind the facing redistributed and a load shift phenomenon occurred from the abutment facing to the pile, with significant stress release behind the facing and stress concentration behind the pile at the middle height of the abutment. Particular attention should be paid to the interaction mechanism between the embedded pile and reinforced soil, as well as the thermal-induced behaviors of embedded MSE abutments.]]></description><pubDate>Fri, 23 Jan 2026 09:20:54 GMT</pubDate><guid>http://pubsindex.trb.org/view/2655740</guid></item><item><title>The Role and Optimization of Guide Vane Inclination in Suppressing Vortex-Induced Vibrations of Π-Shaped Girders</title><link>http://pubsindex.trb.org/view/2655739</link><description><![CDATA[The Π-shaped composite girder is widely used in the construction of long span cable-stayed bridges, but its poor vortex-induced vibration (VIV) performance seriously affects its application prospects. The VIV performance and aerodynamic optimization measures of a Π-shaped composite girder are studied by using wind tunnel tests. The tests show that the VIV of the original Π-shaped section occurs at each wind attack angle, and the amplitude can be reduced by setting guide vanes and the lower central stabilizer at the bottom of the I-beam. The change of the inclination angle of guide vanes has a significant impact on the VIV suppression performance of the combined aerodynamic measures. The configuration with a 30° guide vane inclination angle exhibited optimal performance for VIV suppression, achieving the greatest reduction in amplitude. The VIV suppression mechanisms of the combined aerodynamic measure are studied by using computational fluid dynamics (CFD) numerical simulation. The calculation results show that the windward-side guide vane in the 30° inclination guide vane combination measure can significantly improve the flowing condition around the upstream section and cooperate with the lower central stabilizer to weaken the Kármán vortex of the Π-shaped section wake, thereby suppressing the girder’s VIV. Changing the inclination angle of the guide vane not only affects the generation of vortices near the guide vane itself but also affects the improvement of the lower central stabilizer on the vortex shedding state on the lower side of the section, thereby significantly improving the VIV suppression performance of the combined aerodynamic measure.]]></description><pubDate>Fri, 23 Jan 2026 09:20:54 GMT</pubDate><guid>http://pubsindex.trb.org/view/2655739</guid></item><item><title>Attaching Steel Bridge Rail Posts Directly to Bridge Decks: Design Procedures, Best Practices, and Case Studies</title><link>http://pubsindex.trb.org/view/2652004</link><description><![CDATA[Steel post-and-beam railings which attach directly to bridge decks are beneficial for a variety of reasons, including reduction of dead weight, unrestricted drainage, aesthetics, and rapid installation. However, because of a long-standing convention holding that the use of steel posts without curbs is likely to result in costly deck damage, steel bridge railings are used less frequently than concrete parapets and curbed steel railings. Under NCHRP Project 12-119, this convention was challenged, and an updated methodology for evaluating/designing bridge decks to support steel posts was developed. The method is compatible with both damage-mitigating and damage-permitting design philosophies. Failure of the deck slab is characterized as a trapezoidal yield-line mechanism, which can be adjusted to account for local punching shear damage below the post. To develop the methodology, in this research a physical impact test was performed on an instrumented steel post and bridge deck specimen. A calibrated LS-DYNA model was then developed and used to create a data pool consisting of simulated pushover tests of parametric variations and in-service railing models from which design guidance was extracted. General guidelines and best practices for attaching steel posts to bridge decks, which are consistent with the updated methodology, are presented in this paper alongside general recommendations for selecting appropriate post sizes for a common bridge deck designs.]]></description><pubDate>Mon, 12 Jan 2026 10:50:06 GMT</pubDate><guid>http://pubsindex.trb.org/view/2652004</guid></item><item><title>Temperature Analysis of Single-Box Three-Cell Concrete Box Girder Considering Actual Wind Field</title><link>http://pubsindex.trb.org/view/2647055</link><description><![CDATA[Current research on single-box multi-compartment concrete box girders ignores the effect of the wind field on the temperature distribution of the box girder. Incoming wind has a significant effect on the convective thermal transfer coefficient on the surface of the box girder structure, and affects the temperature field analysis accuracy. In this paper, a single-box three-cell concrete box girder is taken as the research object; the temperature field model of the world’s largest single-box three-cell concrete box girder is established, and a dot matrix temperature field modeling test is conducted. Based on the wind field distribution characteristics of the single-box three-cell concrete box girder, more accurate convective thermal transfer boundary conditions were determined. The model’s temperature field and gradient distributions were validated and compared with traditional methods that neglect wind effects. The results showed a 71% reduction in root mean square error and a 69% reduction in mean absolute error, with the vertical temperature gradient in the web closer to actual conditions. To solve the difficult problem of determining the thermal boundary conditions at different cross sections, a wind speed reduction coefficient model of a concrete box girder with variable cross section and a single-box and three rooms is established, which is linearly related to the aspect ratio of the box girder. The influence of incoming wind speed and box girder geometry on the wind speed reduction coefficient at different cross sections of the bridge is quantitatively evaluated, and the empirical formula for the convective heat transfer coefficient used in previous research is improved.]]></description><pubDate>Thu, 08 Jan 2026 10:29:52 GMT</pubDate><guid>http://pubsindex.trb.org/view/2647055</guid></item></channel></rss>