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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Bearing Capacities and Characterization of Compressible Clayey and Silty Foundation Soils in Oklahoma</title>
      <link>https://trid.trb.org/View/2683250</link>
      <description><![CDATA[This study develops a characterization of alluvial soils in two river  systems from the surface down to bedrock. Study sites were located in  alluvial deposits where fill settlement is a problem. Continuous undisturbed soil samples were taken. Unconfined compression and consolidation tests were run on the soil layers. The field testing included the standard penetration test. Inclinometers were installed in an attempt to determine if creep existed in the weak soil layers of the alluvium.]]></description>
      <pubDate>Mon, 13 Apr 2026 16:27:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2683250</guid>
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    <item>
      <title>Effect of Footing Size and Ground Heterogeneity on Bearing Pressure-Settlement Response of Circular Footings on Compressible Ground</title>
      <link>https://trid.trb.org/View/2640170</link>
      <description><![CDATA[Most of the bearing capacity theories consider the soil to be homogeneous and incompressible. However, ground is nonhomogeneous both in terms of material and strength. Undrained shear strength varies linearly with depth for a young normally consolidated deposit. This study analyzes the response of circular footings of different sizes resting in normally consolidated soils, accounting for stress-induced heterogeneity of strength with depth. Finite element axisymmetric analysis is carried out to evaluate the bearing pressure versus settlement responses for footings on or in normally consolidated ground. Results show that undrained bearing pressure increases with the rate of increase of undrained strength with depth, unlike the case with footings on or in homogeneous soils. Bearing pressure increments are higher for large-size circular footings, located at larger embedment depths. Correction factors, Fₙₕ, for bearing capacity are presented as a function of footing size and embedment depth, and rate of increase of undrained strength with depth for footings. Results are applied to circular footing resting in Mexican clay for illustration.]]></description>
      <pubDate>Mon, 29 Dec 2025 09:32:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/2640170</guid>
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    <item>
      <title>Guidelines for Using Lightweight Fills in Transportation Infrastructure Applications</title>
      <link>https://trid.trb.org/View/2604251</link>
      <description><![CDATA[This research investigated the use of lightweight fills as an alternative to conventional fills in transportation infrastructure, particularly for fill applications on soft, compressible soils. The study synthesized current practices through a literature review, survey of state departments of transportation (DOTs), evaluation of case studies, and material costs. Through this research, it was concluded that lightweight fills are widely applied nationwide and can significantly reduce vertical and lateral stresses, but their broader adoption is limited by high costs, limited contractor experience, and insufficient long-term performance data. Additionally, the Texas Department of Transportation (TxDOT) is provided with recommendations for practical design and construction guidelines, cost considerations and limitations, which can be used to inform project planning and encourage applications of lightweight fills in Texas.]]></description>
      <pubDate>Thu, 16 Oct 2025 17:02:35 GMT</pubDate>
      <guid>https://trid.trb.org/View/2604251</guid>
    </item>
    <item>
      <title>Long-Term Performance Evaluation of Reinforced Embankment Test Sections Over Extremely, Soft Compressible Soil: A Case Study in Louisiana</title>
      <link>https://trid.trb.org/View/2601321</link>
      <description><![CDATA[Constructing roads across the swamps of south Louisiana has created unique challenges. Soft saturated subgrades often exist, causing embankment stability and long-term settlement issues that must be considered in the geotechnical design of these embankments. Historically, sand embankments constructed over soft soil required wide stability berms to prevent deep-seated failures (no improvement with depth). Although geosynthetic reinforcements have allowed sand embankment construction directly on the natural ground without muck excavations, the weight has caused serious settlement problems. Some roadways have settled to the extent that under extreme flood conditions, the roadway was partially underwater, restricting hurricane evacuation operations. Roadway undulation caused by differential settlement also produced a "roller coaster" ride. The objective of this study is to evaluate the long-term performance of test sections with geosynthetics and lightweight fill material. During this study, the long-term performance of five embankment test sections constructed on soft compressible soils after construction was investigated. It involved the design, construction, and long-term monitoring of these test sections on a relocation project for U.S. 90, a major arterial road connecting New Orleans with Lafayette through southern Louisiana (eventually I-49), over a period of time extending from 1990 to 1999. This evaluation compiled both past and present data into a result, providing insights into the long-term performance and stability of these embankments.]]></description>
      <pubDate>Thu, 18 Sep 2025 15:40:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2601321</guid>
    </item>
    <item>
      <title>Develop Settlement Criteria and Design Approach for Embankments and Retaining Walls Built on Compressible Soils</title>
      <link>https://trid.trb.org/View/2553148</link>
      <description><![CDATA[The overarching objective of this project is to identify settlement criteria for embankments and retaining walls and develop a systematic soil improvement design tool to facilitate the method selection and construction time and cost estimation. There is a consensus that the post-construction settlement has profound impacts on the service conditions of roadways and bridge approaches. However, there is no widely accepted settlement criterion in the nation, so each states practice differently. This project surveyed 49 state departments of transportation (DOTs) on their settlement criteria based on their zoning of bridge approach embankments. 23 out of 49 state DOTs responded to the survey and provided their information on settlement requirement and zoning. The collected data indicate that most state DOTs have their own settlement requirements for embankments, particularly, for the embankment supporting the bridge approaches. However, the requirement varies significantly. In addition, the zoning criteria used by these responding states are also drastically different and some state DOTs do not use zoning, instead, they use one criterion for its embankments regardless of its distance from the bridge. Among the states that have no existing statewide settlement requirement, they either allow each district to use its own criteria or allow the responsible project engineer to determine the allowable settlement based on the project condition. Considering that fact, a calculation tool was developed, which allows users to assess the construction time and cost at a user-specified allowable settlement. The developed calculation tool was validated by using extensive published field data. By using the tool, the user can assess multiple soil improvement methods and then select the best one or multiple technologies to achieve a balance between cost and construction time.]]></description>
      <pubDate>Thu, 15 May 2025 08:26:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2553148</guid>
    </item>
    <item>
      <title>A Compilation of Transportation Projects Using Rigid Inclusions</title>
      <link>https://trid.trb.org/View/2452731</link>
      <description><![CDATA[Many transportation projects involve building, replacing, or widening roadways and raising grades, which often requires the construction of embankments, ramps, or retaining walls. This construction involves placing thick layers of fill over large areas, which transfers stress deep within the soil profile, causing even deep layers of compressible soils to settle. To provide the general public with well-maintained and functional infrastructure, compressible soils are often spanned using piles or rigid inclusions (RI) to reduce excessive long-term settlement of the structures above them. RIs are small-diameter fully grouted columns that are installed to reduce settlement and increase bearing capacity. Though they behave similarly to piles, RIs generally offer a more economical solution than piles because they are unreinforced elements designed without pile caps. Additionally, the design of the load transfer platform (LTP) can be optimized from the traditional thick, heavily reinforced platforms associated with pile-supported embankments. Over the past 18 years, the authors have used RIs to successfully provide support for over 85 embankment and retaining wall transportation projects in 23 states. The types of projects vary widely, as do the ground conditions, applied loads, and optimized solutions provided. The authors' design and installation processes have evolved to include the experience they have gained on these projects, both in design and with the actual performance of the installed systems. Many of these transportation projects include instrumented monitoring programs to evaluate settlement and lateral movement. This paper will include some of the key considerations for the design of safe and optimized RI support for embankments and walls as well as tabulated summaries of past projects completed by the authors. The authors will address the key risks associated with the design of RIs for transportation projects and the role of stability in the design. The tabulated results will contain information about the supported structures, the soil profiles, the resulting RI solutions, and comparisons between the design-estimated and measured movements, where possible.]]></description>
      <pubDate>Sat, 30 Nov 2024 11:49:35 GMT</pubDate>
      <guid>https://trid.trb.org/View/2452731</guid>
    </item>
    <item>
      <title>Tunnel Performance under Extreme Environmental Effects</title>
      <link>https://trid.trb.org/View/2291269</link>
      <description><![CDATA[Environmental effects in strategic underground infrastructure, such as extreme water extraction, extreme floods, material deterioration due to water infiltration and ground movement under sustained and seismic loading, can significantly affect its short, medium, and long-term performance. Furthermore, these effects are critical in densely populated cities, where the overall safety of a particular structure can be jeopardized if those effects are ignored, and poor geotechnical conditions prevail, such as in Mexico City, where high plasticity and highly compressible clay is found. This paper presents a novel methodology based on a coupled field monitoring and numerical approach to assess the performance of strategic underground infrastructure under environmental effects. The method allows to establish, from a surrogate model derived from the analysis of several scenarios, an optimum range for the expected performance, establishing a lower and upper-efficiency curve as a function of the environmental parameters measured. The method is introduced through a case study corresponding to a 9.1 km long tunnel. Through the analysis of the results obtained, it was possible to evaluate the short to long-term behavior of a tunnel and eventually propose mitigation measures to enhance its expected performance.]]></description>
      <pubDate>Thu, 21 Dec 2023 16:35:28 GMT</pubDate>
      <guid>https://trid.trb.org/View/2291269</guid>
    </item>
    <item>
      <title>Analytical Approach to Evaluating the Influence of the Compressible Layer on the Time-Dependent Response of Deep Soft-Rock Tunnels</title>
      <link>https://trid.trb.org/View/2174769</link>
      <description><![CDATA[The application of the compressible layer in linings provides a feasible and safe solution to addressing the problems of the excessive deformations of surrounding rocks and support failure in the deep soft-rock tunnels. However, there still has not been a well-constructed method to report the mechanical responses of the tunnels supported by such a support system. The objective of this study is to provide an analytical approach to estimating the influence of the compressible layer on the tunnel performance. The mechanical model of the tunnel supported by the compressible layer and concrete lining within the viscoelastic–plastic geomaterial was established. The corresponding analytical solutions for the tunnel displacement and lining pressure are provided, where the influences of the stress path, tunnel face advancement, and installation delay of supports are considered. The effectiveness and reliability of the proposed model are validated by using the numerical calculation, and a good agreement between the analytical and numerical results are obtained. Finally, a comprehensive parametric investigation is carried out, including the influences of the yielding stress, yielding length and elastic modulus of the compressible layer and the lining installation time. The important findings are provided and several useful recommendations are proposed for the design of this supporting system.]]></description>
      <pubDate>Wed, 28 Jun 2023 16:29:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2174769</guid>
    </item>
    <item>
      <title>Three-dimensional modelling of a multi-span masonry arch bridge: Influence of soil compressibility on the structural response under vertical static loads</title>
      <link>https://trid.trb.org/View/1721622</link>
      <description><![CDATA[The paper presents the results of an experimental and numerical study aimed at investigating the structural response of a historical multi-span masonry arch bridge. The bridge, named Azzone Visconti bridge, was built in the 14th century and is placed in northern Italy. The bridge behaviour under static loads was checked by means of a sequence of acceptance load tests designed accordingly to the provisions of the Italian Code. A detailed 3D finite element model was built based on previous extensive geometric survey, historical data and mechanical characterization of both the soil constituting the riverbed and the stone masonry constituting the piers. Three different models describing the mechanical behaviour of the foundations have been implemented to include soil-structure interaction. A comparison between the experimental measures obtained during the acceptance load tests and the numerical results has allowed establishing the reliability of the models. Post-test nonlinear finite element analyses have allowed the evaluation of the bridge mechanical behaviour under vertical static loads. The influence of the different soil-structure interaction models adopted in the analyses on the evaluation of the bridge structural response is widely discussed.]]></description>
      <pubDate>Mon, 27 Jul 2020 09:39:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/1721622</guid>
    </item>
    <item>
      <title>Development of Statistical Models to Predict the Compressibility of Florida’s Soils</title>
      <link>https://trid.trb.org/View/1667512</link>
      <description><![CDATA[The magnitude of the overall settlement depends on several variables such as compression index (Cc), recompression index (Cr), and secondary compression index (Cα), which are determined by a consolidation test. However, the test is time consuming and labor intensive. Correlations have been developed to approximate these compressibility indexes to supplement but not eliminate a geotechnical sampling and testing program. In this study, a data-driven approach has been employed to estimate Cc, Cr, Cα, and coefficient of consolidation (Cv). In this project, a support vector machine (SVM) classification technique was used to determine the number of distinct models to be developed. The statistical models were then constructed through a forward-selection stepwise regression procedure. Eight variables were used, and these variables included the moisture content, automatic hammer standard penetration test (SPT) blow count, overburden stress, fines content (-200), liquid limit, percent organic content, plasticity index, and specific gravity. The best performing statistical models of soil compressibility were constructed for the classified soil types. In addition, reduced models that minimize the number of variables were constructed for more practical usage. It is recommended that only the models with R2 > 0.5 be used for engineering analysis. Lastly, the correlation between soil compressibility between CPT tip resistance (qc) was checked. There is a general trend that Cc and Cr decrease as qc increases; however, the correlation is not strong due to the limited dataset. Data collected under a controlled environment will be able to improve the correlation quality.]]></description>
      <pubDate>Fri, 22 Nov 2019 16:49:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/1667512</guid>
    </item>
    <item>
      <title>Deformation of Compressible Layers Below Pile Foundations of a High-Speed Railway</title>
      <link>https://trid.trb.org/View/1605576</link>
      <description><![CDATA[New installation methods and techniques using single-point settlement gauges to monitor the compression deformations of pile shafts and soil layers below the pile bottom were developed. A field study was conducted at a test site of the Beijing–Shanghai high-speed railway, and a 3D finite-element analysis was performed to analyze the deformation behavior of the pile foundation. The measured compression deformations of the pile shafts from the single-point settlement gauges agreed well with the values obtained from the strain gauges, which validated the effectiveness and feasibility of the developed methods and techniques. During the construction of the high-speed railway, the pile top settlement–time curve presented a ‘ladder’ shape and then increased with time before gradually stabilizing. The compression deformations of the subsoil layers within 20–30 m below the pile bottom were not significantly different, and the average unit compression deformation under 20 m below the pile bottom remained approximately constant after construction. The axial force and tip resistance of the pile shaft increased during the consolidation of the soils surrounding the pile shaft and might result in an increase of the compressions of the pile shaft and subsoil layers. The thicknesses of compressible layers (hc) of the tested pile foundations were determined using a deformation ratio method and were approximately 15.0 m. These results demonstrate that the developed methods and techniques are useful for studying the compression deformations of subsoils below the pile bottom (especially for super-long piles).]]></description>
      <pubDate>Thu, 27 Jun 2019 14:53:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/1605576</guid>
    </item>
    <item>
      <title>Evaluation of Secondary Consolidation Settlement Associated with Embankment Construction for Fast-paced Transportation Projects in Utah</title>
      <link>https://trid.trb.org/View/1597513</link>
      <description><![CDATA[This report discusses the design and implementation of surcharging technology in terms of the required laboratory, field and engineering evaluations. It is hoped that such information will provide a more consistent and technically defensible rationale for deploying this technology on highway projects constructed atop soft soils. Surcharging or preloading of the earthen embankments and underlying compressible soils is the most commonly deployed strategy to reduce the magnitude of secondary compression. Surcharging or overconsolidating of the foundation soils can be used to reduce the post-construction secondary settlement. In the course of this research, twenty-two consolidation tests and eighty-eight time rate tests were performed on Pleistocene and recent fine-grained, cohesive, lacustrine deposits comprised of Lake Bonneville and more recent clays, most likely of Utah Lake origin located along the Wasatch Front in Utah. Prior to analyzing the data, the test results were screened using the sample quality designation (SQD). Plots of the adjusted amount of surcharge (AAOS) were plotted versus the normalized rate of secondary settlement (Cₐ’/Cₐ) and compared with the research performed by Ng (1998). The data from this thesis plots higher than that reported by Ng (1998). This higher trend agrees better with the long-term settlement performance monitoring data obtained from the I-15 Reconstruction Project in Salt Lake County, Utah. Data from the time rate tests were used to determine the Cₐ/compression ratio (CR) ratio, giving a mean value of Cₐ/CR = 0.0442. This value compared favorably with the research performed by Ng (1998), which had a value of Cₐ/CR = 0.0433. Also provided with this report is a recommended method for designing surcharge fills considering post-construction (i.e., secondary compression) settlement.]]></description>
      <pubDate>Fri, 26 Apr 2019 16:58:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/1597513</guid>
    </item>
    <item>
      <title>Cooperative Geotechnical Designs to Build on Liquefiable and Compressible Soil in Salem, Massachusetts</title>
      <link>https://trid.trb.org/View/1480047</link>
      <description><![CDATA[The Massachusetts Bay Transit Authority (MBTA) is addressing accessibility throughout their facilities. The Commuter Rail station in Salem, Massachusetts is upgrading their facility to improve site accessibility and increase parking capacity. Proposed improvements include a parking garage replacing the existing parking lot, a pedestrian bridge replacing the existing stairway connecting track level with downtown Salem, and a full-length high-level platform. Historical records, a geophysical survey, and an archaeological survey indicate structural remains from an historic train depot are largely intact beneath the surface of the existing lot. Subsurface explorations encountered fill overlying loose saturated sands above 40 feet of soft, compressible marine clay deposits extending to competent argillite rock at 60-80 feet below grade. Deep foundations bearing on rock were recommended for structural support of the garage, bridge, and platform. Potentially liquefiable sands, the potential for lateral spreading, and a poor seismic site classification exist at the site. Ground improvement techniques were recommended to improve the subsurface soil conditions and limit liquefaction and lateral spread potential. Several value-engineering options were explored, including options to replace traditional deep foundations with drilled displacement columns for garage support, using shallow retaining wall foundations for platform support, and using a slab-on-grade instead of a structural slab. The resulting cooperative designs required additional coordination between the design team to maximize efficiency of the project budget.]]></description>
      <pubDate>Thu, 24 Aug 2017 09:46:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/1480047</guid>
    </item>
    <item>
      <title>The Anatomy of A Challenging Construction Project, Extension of the Roadway Across a Celery Bog, West Lafayette, Indiana</title>
      <link>https://trid.trb.org/View/1472365</link>
      <description><![CDATA[Rapid population growth of West Lafayette, IN, adjacent to Purdue University, required the city to widen the road across the Celery Bog from two lanes to four. Celery Bog is a marsh containing thick deposits of peat and marl that fill a large kettle lake of Wisconsin age. Distance across the bog was about 800 feet. An embankment was required to raise the elevation of the road and to extend it from two lanes to four. The embankment portion across the bog failed as a classic rotational slump during construction. Some concerns have arisen in retrospect regarding the thoroughness of the exploration program, laboratory testing prior to construction, earthwork placement, and construction supervision.  Next, to stabilize the bog crossing, grout columns were placed through the soft soils into the glacial till below. However, the subgrade mat below the pavement failed to transfer loads onto the piles, placed at six-foot centers, causing the road to develop a washboard effect. In an attempt to add stiffness to the subgrade the city repaved the road with an asphalt overlay but the washboard effect returned. As a last resort a bridge was constructed over the bog, which nearly doubled the cost of the road-widening project. Steel H-piles approximately 100 feet in length, were driven into the glacial till and gravel layer to support the bridge. The original cost of about $3 million was increased to about $12 million for the total road project extending about 6350 feet in length. Litigation between the contractor and the state highway department was conducted in an attempt to determine the cause of failures and the level of responsibility.]]></description>
      <pubDate>Thu, 29 Jun 2017 13:49:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/1472365</guid>
    </item>
    <item>
      <title>Geotechnical Designs to Build on Liquefiable and Compressible Soil in Salem, Massachusetts</title>
      <link>https://trid.trb.org/View/1470089</link>
      <description><![CDATA[The Massachusetts Bay Transportation Authority (MBTA) is addressing accessibility throughout their facilities. Improvements at the Commuter Rail Station in Salem, Massachusetts include a five-level parking garage replacing the existing parking lot, a pedestrian bridge replacing the existing stairway connecting track level with downtown Salem, two accessible elevators, and a full-length accessible high-level platform. Subsurface explorations at the site encountered fill overlying loose, potentially liquefiable saturated sands, overlying soft marine clay deposits extending to till and rock at about 60 to 80 feet depth. Deep foundations bearing on rock were recommended for structural support of the garage, bridge, and platform. Ground improvement using vibratory stone columns (VSCs) was also recommended to address the liquefaction and lateral spreading potential, and to improve the seismic site classification from Class F to Site Class E. The project team evaluated value-engineering options. The final design included the installation of over 470 Controlled Modulus Columns™ below the garage and bridge footings. Over 825 VSCs up to 30 feet in depth were installed below the parking garage and platform. Post-VSC treatment testing was conducted during construction to review compliance with the specified performance criteria. The cooperative design and installation required coordination between the design and construction teams to maximize cost and schedule efficiency for the project. These methods allowed the project to move forward, ultimately saving the client millions of dollars in construction costs.]]></description>
      <pubDate>Wed, 21 Jun 2017 17:16:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/1470089</guid>
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