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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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    <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>
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    <item>
      <title>Behaviour of pile caps with socket connections and different embedment depths under vertical loads</title>
      <link>https://trid.trb.org/View/2627574</link>
      <description><![CDATA[Socket connections have emerged as an up-and-coming approach for precast bridge substructures. It enables a large construction tolerance, rapid assembly, low construction risk, and seismic integrity. However, how the embedment depth affects the vertical load-bearing capacity of pile caps remains unclear. This capacity strongly depends on the vertical load-transfer mechanism at the column-pile cap interface. Experiments were conducted on one cast-in-place pile cap and two socket connected pile caps with varying embedment depths to reveal the embedment effect on the load-transfer mechanism. The results show that the load transfer from the column to the pile cap mainly depends on the interface between the upper part of pile cap and column. Increasing the embedment depth has a minimal effect on the vertical load-bearing capacity.]]></description>
      <pubDate>Fri, 09 Jan 2026 08:44:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2627574</guid>
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    <item>
      <title>Pile Deformation Stresses and Strains in Integral Abutment Bridges</title>
      <link>https://trid.trb.org/View/2617986</link>
      <description><![CDATA[Integral abutment bridges have definite advantages, including less deck deflection than bridges with simply supported members, simpler construction, and lesser maintenance of the abutment and superstructure supports. This investigation examined the extent of strains induced by thermal expansion and contraction in driven piles and the reinforcing bars that connect the pile cap to the abutment diaphragm. Bridges selected for strain gage instrumentation had single and multiple spans. Three bridges used HP 12 x 53 piles oriented in the “strong” X-X axis and one bridge used shell piles. Strain gages and wires were armored with epoxy and attached to piles and reinforcing bars. Results indicated that piles had variable stresses as function of depth from the top of the pile to their points of fixity. Deflections in several piles did not conform to the deformed shape of a cantilever pile with fixed end loading as predicted by theoretical mechanics. Some piles exhibited the onset or presence of a plastic hinge. Differences in soil compressive strengths at various depths also influenced the deformation behavior of the pile. Mean stresses that were established in several piles were substantial and generated some concern as to factors of safety of piles with respect to fatigue life. HP piles were evaluated in terms of their expected fatigue life by the widely used Goodman failure equation and related fatigue data of ASTM A36 structural steel and ASTM A706 and A615 rebars. The effects of mean and alternating stresses and corrosion fatigue data of A36 steel were also included. Rebars at the pile cap were particularly vulnerable where several had clearly sustained stress levels significantly beyond the AASHTO high cycle fatigue limit for reinforcing bars. Recommendations to extend the life of piles subjected to stresses above their yield strength and corrosion in soils with low resistivity include: (a) thermally sprayed zinc or aluminum coatings; (b) hot dip galvanizing of the piles; (c) coating the piles with fusion-bonded epoxy and (d) cathodically protecting them with replaceable magnesium or zinc or aluminum sacrificial anodes, depending on the prevalent soil resistivity.]]></description>
      <pubDate>Sat, 27 Dec 2025 16:06:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/2617986</guid>
    </item>
    <item>
      <title>Three-dimensional strut-and-tie models for reinforced concrete pile caps subjected to concentric and eccentric column loads</title>
      <link>https://trid.trb.org/View/2625487</link>
      <description><![CDATA[This study proposes two types of three-dimensional strut-and-tie models for the rational and effective design of square four-pile reinforced concrete pile caps subjected to concentric and eccentric column loads. To enhance the practical applicability of the proposed models, effective strength values for strut and nodal zones were determined through iterative numerical analyses across various combinations of key design parameters, and effective strength equations for the strut and nodal zones were formulated by integrating linear regression analysis, a machine learning technique, with grid search methods. The primary design variables of strength equations included the shear span-to-depth ratio for concentric loads and both the shear span-to-depth ratio and eccentricity ratio for eccentric loads. To validate the proposed models and equations, the ultimate strength of 190 experimental pile cap specimens and 35 numerical pile cap models was predicted. For pile caps under concentric loads, the ratio of experimental to predicted strength (with coefficient of variation) was 1.04 (17.5%), showing improved accuracy and consistency compared to existing design codes (mean strength ratio of 1.45–2.15, coefficient of variation of 47.4%–60.5%). For eccentric loads, the ratio was 1.07 (12.6%), indicating significantly enhanced predictive performance compared to existing design codes (mean strength ratio of 2.17–4.62, coefficient of variation of 32.6%–66.8%). These results confirm that the proposed three-dimensional strut-and-tie models and effective strength equations effectively capture the complex three-dimensional stress flow and reinforcement effects in pile caps, enabling more accurate and reliable evaluation of ultimate strength under both concentric and eccentric loads compared to current design codes.]]></description>
      <pubDate>Tue, 25 Nov 2025 16:57:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/2625487</guid>
    </item>
    <item>
      <title>Performance comparison of capped pile and piled beam support systems for embankments on soft soils</title>
      <link>https://trid.trb.org/View/2597153</link>
      <description><![CDATA[Geographical locations with soft soil present significant challenges for constructing transportation earthworks due to the soil’s high compressibility and low shear strength. Pile-supported embankments are a proven solution; however, the relative performance of different pile–cap–beam configurations under equal area coverage ratio (ACR) conditions remains insufficiently quantified. This study investigates the hydromechanical behavior of soft soils improved using Capped Pile Supported Embankment (CPSE) and Piled Beam Supported Embankment (PBSE) systems through fully coupled three-dimensional numerical analyses calibrated against field data. The models incorporate geosynthetic-reinforced cushion layers and examine basal pressures, excess pore pressures, settlements, lateral displacements, and pile/beam deformation patterns. Results show that, at equal ACR, CPSE transfers vertical loads more directly to piles, reducing centerline settlement, whereas PBSE provides greater lateral restraint, reducing horizontal movement at the slope toe. Parametric analyses for embankments of 5 m and 10 m height reveal that PBSE generally offers higher stability, with optimal ACR ranges depending on embankment height. These findings provide a controlled baseline for performance comparison and inform future optimization, including considerations for traffic-induced bending, cyclic loading, and seismic effects.]]></description>
      <pubDate>Thu, 30 Oct 2025 08:49:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/2597153</guid>
    </item>
    <item>
      <title>Waterline Pile Cap Footings for Bridges using Large Diameter FRP Reinforcing – Material Characterization and Design</title>
      <link>https://trid.trb.org/View/2601703</link>
      <description><![CDATA[The durability of coastal bridge structures is significantly impacted by the corrosion of steel reinforcement, particularly in waterline pile cap footings exposed to aggressive marine environments. This study investigates the feasibility of using large-diameter glass fiber-reinforced polymer (GFRP) bars as a corrosion-resistant alternative to traditional steel reinforcement. The research includes a comprehensive literature review, material characterization, and structural analysis to develop design specifications for #11 GFRP bars. Experimental testing, including tensile, bond, and durability assessments, was conducted to establish mechanical properties and ensure compliance with American Association of State Highway and Transportation Officials (AASHTO) and Florida Department of Transportation (FDOT) requirements. Structural performance evaluations were carried out using computational modeling tools to validate the design methodology for GFRP-reinforced pile cap footings. The findings confirm that #11 GFRP bars demonstrate adequate strength, durability, and environmental resistance for bridge applications, offering a sustainable solution to extend service life and reduce maintenance costs. Design examples are provided to facilitate implementation in practice. This research supports the development of material acceptance criteria and refined design guidelines, promoting wider adoption of GFRP reinforcement in marine bridge construction and enhancing infrastructure resilience in coastal regions.]]></description>
      <pubDate>Mon, 22 Sep 2025 16:59:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/2601703</guid>
    </item>
    <item>
      <title>Monitoring the Foundations of a Bridge during Construction and While in Service</title>
      <link>https://trid.trb.org/View/2536000</link>
      <description><![CDATA[This paper presents the results of the monitoring of the performance of the foundations of the Sagamore Parkway Bridge over the Wabash River in West Lafayette, Indiana, during construction and while in service. One of the interior bridge piers (Pier 7) and its supporting 3×5 pipe pile group were instrumented with vibrating-wire strain gauges to study the bridge response to dead and live loads, the load transfer mechanism from the bridge pier to the pile cap and group piles, and the distribution of loads among the individual piles in the pile group. The measured loads and the estimated design loads were compared to verify the assumptions made in the design of the bridge foundations. The load–settlement response of Pier 7 was almost linear during bridge construction, and no significant changes were observed in its load–settlement response when the bridge was in service. Analysis of the loads carried by different components of the foundation elements showed that, at the end of bridge construction, the piles carried about 77% and the pile cap carried the remaining 23% of the total superstructure load from Pier 7. The contribution of the pile cap to the total foundation capacity, which is not usually considered in bridge foundation design, was considerable in this case. Consideration of the additional load carrying capacity coming of the pile cap may lead to more-economical design when scour is not a concern and the additional capacity is not negligible.]]></description>
      <pubDate>Mon, 12 May 2025 09:46:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/2536000</guid>
    </item>
    <item>
      <title>Evaluation of structural cracks in inverted T-pier caps of super T-girder bridges</title>
      <link>https://trid.trb.org/View/2528607</link>
      <description><![CDATA[Survey results from actual projects that have been put into operation in the Southern region of Vietnam show cracks on the shoulder surface of the inverted-T bent caps of the simple-span Super T-girder bridge. The research problem posed for the article is to determine the cause of these cracks. In the article, the finite element method is used to analyze and calculate the mechanical behavior of beam under the effect of dead load and live load HL93. The 3D model of the bridge pier structure is close to reality based on measurement results and design documents. Reinforcements are declared in detail in the model as bar elements. Assume that the reinforcement completely bonds to the concrete. Concrete has a compressive strength of 30MPa, and steel has a yield strength of 420MPa as shown in the design documents of the bridge pier. During the analysis process, the non-linear behavior of both steel and concrete is considered to improve accuracy. The results of the analysis are the mechanical behavior of the pier caps such as stress components in concrete and steel reinforcement. In particular, the results of the non-linear crack analysis show the crack distribution area on the inverted-T bent cap surface and the crack depth. Based on the analysis results, the causes of cracking can be identified, and the level of cracking can be assessed for the structure of the inverted-T bent caps.]]></description>
      <pubDate>Thu, 24 Apr 2025 10:39:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/2528607</guid>
    </item>
    <item>
      <title>Research on the Influence of Load-Bearing Longitudinal Reinforcement on the Cracking Behavior of Inverted-T Bent Cap</title>
      <link>https://trid.trb.org/View/2528462</link>
      <description><![CDATA[Survey results from actual projects show cracks in the pier caps of the Super T girder bridge. This is a type of bridge commonly used in Vietnam today. The problem is that there needs to be solutions to limit these cracks. This article studies solutions to limit cracks by appropriately arranging reinforcement. The authors propose options for arranging load-bearing longitudinal reinforcement that is feasible in practice, technically and economically. Conducting structural analysis for these cases with different longitudinal reinforcement arrangements using the finite element method. The computational model is a 3D model that is close to reality for reliable results. Linear and nonlinear analysis are used simultaneously in the study to clarify the influence of reinforcement arrangement on the behavior of pier cap beam structures such as concrete stress, reinforcement stress, crack width, and crack patterns. From there, there are recommendations on how to arrange load-bearing reinforcement in cap beams.]]></description>
      <pubDate>Wed, 23 Apr 2025 16:15:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2528462</guid>
    </item>
    <item>
      <title>Accelerated Bridge Construction (ABC) Methods for Pile-Footing-Column Systems</title>
      <link>https://trid.trb.org/View/2509057</link>
      <description><![CDATA[
Building on a previous project, the proposed research will advance the accelerated bridge construction method for bridge substructures using steel piles and precast pile caps and columns. The weight of the precast members will be reduced using hollow sections, which in turn will improve both construction tolerances and constructability. The hollow sections will be filled with in-situ concrete. The piles will be designed with temporary collars, which will eliminate the need to wait for the concrete to cure before continuing with the superstructure construction. The proposed research, funded jointly by the California Department of Transportation, will include a large-scale test unit which will incorporate both vertical and battered steel piles. The testing of the system will incorporate service level and extreme loads and ensure dependable performance of the new system and its components. As part of the testing program, the performance of the column and pile foundations will be examined systematically. Analytical models will be developed to realize the observed performance of the test unit and the components. Using the combination of analytical and experimental observations and findings from the previous phase of the project, appropriate design recommendations will be developed for improving bridge construction.]]></description>
      <pubDate>Wed, 12 Feb 2025 18:34:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/2509057</guid>
    </item>
    <item>
      <title>A frictional arch model for pile-cap-beam-supported embankment</title>
      <link>https://trid.trb.org/View/2442265</link>
      <description><![CDATA[The pile-cap-beam-supported (PCBS) system can strength the soil arching effect of embankment, increase the lateral stiffness, bending resistance and vertical bearing capacity of the rigid pile, however there is no frictional soil arch model of PCBS embankment. In this paper, first a frictional arch model for PCBS embankment modified from Russell’s frictional arching model was proposed. The proposed model in this paper considers the algorithm of lateral pressure coefficient k and a changing critical height of soil arch. In this new method, the influence of pile spacing, filling properties, height and pile spacing on critical height soil arch was comprehensively considered. Second, a series of numerical cases were performed to verify the effectiveness of the proposed model and study the arching effect of PCBS embankment. By comparing the vertical stress and settlement between the theoretical and simulation results, the rationality of the proposed method to estimate the stress and critical height of arch was validated. The effectiveness of the proposed method was further validated by comparing loading efficacy to a reported case. Last, the stress and deformation of PCBS and pile-cap-supported (PCS) embankment were analyzed and the superiority of PCBS system in improving the performance of embankment was observed finally.]]></description>
      <pubDate>Thu, 14 Nov 2024 09:49:28 GMT</pubDate>
      <guid>https://trid.trb.org/View/2442265</guid>
    </item>
    <item>
      <title>Application of Thermal Stress Controlling in Construction of Large Bridge Cushion Cap</title>
      <link>https://trid.trb.org/View/2203632</link>
      <description><![CDATA[With respect to the construction of large bridge cushion cap concrete without poured joint in deep water, thermal stress during concrete hardening is destructive to durability. In this paper, a concrete thermal stress physical formula represented by the deformation component and variable temperature component is given based on the analysis of temperature stress influence. The calculation parameters of the main cushion cap with dimension of 113.75 m long, 48.1 m wide, and 13.3m high are determined. Comparison is made between the monitoring value and calculated results, which are obtained by simulation analysis of thermal stress variation during concrete hardening. The analysis shows that rational controlling temperature standard, cooling with cold water pipes, and curing in time play an important role in cracks protection. The dangerous age and the location where cracks could occur are given. These could provide valuable a reference for the design and construction of the other similar projects.]]></description>
      <pubDate>Mon, 29 Jul 2024 16:27:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2203632</guid>
    </item>
    <item>
      <title>Case Study on Design and Construction of Cofferdam with Tie Back for Pile Cap Construction on a River Embankment</title>
      <link>https://trid.trb.org/View/2377714</link>
      <description><![CDATA[The contractor needs to construct a pile cap on the embankment for a six-lane road bridge project across the Hooghly River located near Kolkata, India. The difference in ground level on the land side and riverbed level was more than 11 m. The bottom of the pile cap needs to be constructed 13 m below ground level from the land side. Due to the challenging topography, the contractor has developed a unique system of temporary earth retaining structure using sheet piles as cofferdam with tie-back arrangement and strutting systems as intermediate supports. Analysis of the cofferdam was carried out using WALLAP and PLAXIS, specialized geotechnical software. Since the construction was happening on a perennial riverbank, mitigation of scour, access, equipment placement, navigational channel, and water ingress were the challenges faced by the contractor. This paper will highlight the critical design process of a cofferdam with a tieback system and also bring out the contractor challenges in the construction of a pile cap at a deeper depth on a river embankment.]]></description>
      <pubDate>Tue, 18 Jun 2024 17:22:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/2377714</guid>
    </item>
    <item>
      <title>Study of Hydrodynamic Pressure on the Cylindrical Pile-Cap Pier in Deep Water Subjected to Seismic Action</title>
      <link>https://trid.trb.org/View/2203427</link>
      <description><![CDATA[In the present paper, study on the influence of hydrodynamic pressure on a 40-meter deep pile-cap pier was made on the basis of the engineering project of the Yangtze River Bridge #3 in Nanjing. Hydrodynamic pressure of the pile-cap pier was evaluated using a three-dimensional finite element model proposed for investigating the dynamical behavior of the pile-cap pier during earthquake in deep water. Two models of the pile-cap pier were proposed for the cases under the conditions with and without water, respectively. The hydrodynamic pressure along the pile caps has increased from top to bottom, and coupling effects would not be ignored in the design of deep-water piers. The numerical results were compared with those from a shaking table experiment, showing a good agreement with each other, especially in the displacement results and mode analysis of the structure.]]></description>
      <pubDate>Fri, 31 May 2024 16:49:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2203427</guid>
    </item>
    <item>
      <title>Concrete-Filled Steel Tube to Concrete Pile Cap Connections – Further Evaluation/Improvement of Analysis/Design Methodologies</title>
      <link>https://trid.trb.org/View/2353375</link>
      <description><![CDATA[This research project focuses on the structural behavior of concrete-filled steel tube (CFST) to concrete pile cap connections, a critical component in many Montana bridges. A series of four experimental pile cap connection specimens were designed and tested to assess the influence of key parameters such as specimen scale, concrete strength, and the incorporation of U-bars on the overall connection performance. The findings from this research revealed that all specimens, barring the specimen with U-bars, displayed consistent moment-drift responses, damage progression, and failure mechanisms within the concrete cap. The inclusion of U-bars notably increased the connection capacity by about 50%, altering the failure mechanism to a plastic hinge formation in the CFST pile. Additionally, the study validated the efficacy of a novel moment-rotation methodology for predicting the capacity of cap connections, with an average measured-to-predicted ratio of 0.95 and a coefficient of variation of 10%. However, this methodology showed a tendency to overpredict capacities in connections without U-bars and underpredict in those with U-bars. Overall, this research provides valuable insight into the behavior of these critical connections under diverse conditions and demonstrates the efficacy of the moment-rotation methodology.]]></description>
      <pubDate>Mon, 15 Apr 2024 08:38:34 GMT</pubDate>
      <guid>https://trid.trb.org/View/2353375</guid>
    </item>
    <item>
      <title>The selection of an appropriate concrete mixture for casting a pile cap in hot weather using 3D finite element model</title>
      <link>https://trid.trb.org/View/2302433</link>
      <description><![CDATA[In this study, the finite element model (FEM) was developed to select an appropriate concrete mixture for a large heavily reinforced bridge pile cap located in Qassim region of Saudi Arabia. The pile cap with dimensions of 9 m x 9 m in plan and 1.8 m in depth was exposed to hot weather conditions in summer season. The heat of hydration in mass concrete results in high temperature gradients across the depth of the concrete creating excessive thermal stresses resulting in micro-cracking at the surface. The concrete mixtures with 30% date kernels ash, 30% fly ash, 30% natural pozzolan, 30% limestone powder, 30% ground granulated slag and 60% ground granulated slag were investigated. The experimental investigations were conducted on the concrete mixtures to determine the mechanical properties, such as tensile and compressive strength, thermal properties, such as thermal conductivity, specific heat, and thermal resistivity, and heat of hydration. The chemical compositions of ordinary Portland cement, date kernels ash, fly ash, natural pozzolan, limestone powder and ground granulated slag were analyzed using wavelength dispersive X-ray fluorescence (WDXRF). Based on the experimental and finite element model results, the concrete mixtures with 30% fly ash (FA), 30% ground granulated blast furnace slag (GGBFS), and 60% GGBFS were found to be less prone to cracking. Notably, the mixture with 60% GGBFS demonstrated the lowest likelihood of cracking, leading to its selection for casting the pile cap.]]></description>
      <pubDate>Wed, 20 Dec 2023 09:31:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/2302433</guid>
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