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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>Mesostructure-Informed Balanced Gradation Design of Rubberized Asphalt Concrete for Dam-Face Seepage Control: Skeleton Optimization and Multi-Performance Enhancement</title>
      <link>https://trid.trb.org/View/2767622</link>
      <description><![CDATA[Conventional gradation design for hydraulic asphalt concrete does not explicitly control coarse-aggregate skeleton formation and internal load-transfer paths, limiting the coordinated optimization of multiple performance requirements for dam facings. To address this limitation, a two-stage mesostructure-informed gradation design method integrating Particle Flow Code (PFC) simulation, X-ray computed tomography (CT) characterization, and systematic performance tests was developed. PFC was first used to optimal coarse-to-fine aggregate ratio based on particle packing and force-chain uniformity, followed by CT-based optimization of the internal coarse-aggregate fractions through contact characteristics, spatial uniformity, and compaction orientation. The results show that a 70:30 coarse-to-fine aggregate ratio achieves the densest packing and the most uniform force-chain distribution.Compared with the specification-recommended hydraulic asphalt concrete gradation, the optimized gradation reduces the strength contribution of mortar-mortar contacts by 21.62% and increases that of aggregate-mortar contacts by 65.63%, reconstructing the internal load transfer network from mortar-dominated bearing to aggregate-mortar collaborative bearing. A 3:1 mass ratio (G2 gradation) of 13.2–9.5mm to 9.5–4.75mm aggregates produced the most favorable mesostructure. The G2 gradation increased residual Marshall stability and low-temperature flexural failure strain by 3.75% and 4.56%, respectively, while reducing the 70 °C slope-flow value by 17.84%. These findings confirm that rationally designing mixture gradation based on quantifiable mesostructural parameters can provide a replicable reference for the proportion design of hydraulic asphalt mixtures.]]></description>
      <pubDate>Wed, 09 Sep 2026 09:03:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/2767622</guid>
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    <item>
      <title>Innovative ultrafine silica-based HFQSAD grouting materials applied for water blocking and reinforcing fractured rock mass in roadways with dispersed water spraying</title>
      <link>https://trid.trb.org/View/2550798</link>
      <description><![CDATA[Dispersed water spraying occurs at roof during the excavation of coal mine roadways. This reduces the load-bearing capacity of surrounding rocks and leads to fractures in the support structures, posing a significant challenge in coal mining. Grouting is a commonly used method to seal water-conducting fractures. Therefore, the work presented the development of a novel ultrafine silica-based high-fluidity quick-setting anti-aqueous dispersions (HFQSAD) grouting material for water blocking and reinforcing fractured rock mass. Additionally, an effective construction process was proposed for controlling dispersed water spraying at the roof of roadways. Results showed that ultrafine silica-based HFQSAD grouting materials had high fluidity, quick setting, strong anti-aqueous dispersion, and good durability. The optimal mixture ratio was determined based on fluidity, initial setting time, uniaxial compressive strength (UCS) at 3 days, and anti-aqueous dispersions. The formulation consisted of a water-cement ratio of 0.45, 0.45 % water reducer, 0.45 % accelerator, 0.2 % PAM, 0.7 % HPMC, and 1 % organosilicon defoamer. According to the independently developed model of dynamic water grouting, the grouting material could seal dynamic water channels and reinforce fractured rock mass. Finally, a new grouting construction process was proposed, utilizing the strategy of "first interception and then blocking for full section treatment" to address water spraying at the roof of the main belt roadway of the west wing in Shanxian Energy Coal Mine. This method could reduce water spraying by 95.2 %, which sealed dispersed water spraying at roof. The effectiveness and feasibility of the ultrafine silicon-based HFQSAD grouting materials and construction process in treating water spraying were confirmed.]]></description>
      <pubDate>Wed, 28 May 2025 10:11:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2550798</guid>
    </item>
    <item>
      <title>Experimental and applied research on similar materials to granular mixtures for solid-liquid coupling model test of an underwater tunnel</title>
      <link>https://trid.trb.org/View/2335928</link>
      <description><![CDATA[To study the response characteristics of seepage and stress fields induced by underwater shield tunnelling in granular mixtures, similar materials suitable for similar simulation experiments were developed based on the solid-liquid coupling similarity theory. Firstly, twenty-five groups of proportioning schemes were established for preparing the specimens using the orthogonal test method, and the aggregates content, fines content, cement-aggregate ratio and coarse-to-fine aggregate ratio were taken as controlling factors. Results show that the content of aggregates and fines are the two critical controlling factors that influence the bulk density; the cement-aggregate ratio is the most significant factor deciding cohesion; and all the factors exert certain controlling effects on the internal friction angle and permeability coefficient. Furthermore, the regulative effects of silicone oil (SO), liquid paraffin (LP), industrial glycerin (IG) and petrolatum jelly (PJ) on the hydro-mechanical properties of similar materials were quantitatively analyzed. After normalizing the effects of different regulators, the goodness-of-fit between the additive amounts of regulators and increase rate of similar materials’ parameters is greater than 0.97, and similar materials have a moderate range of parameters, steady performance, convenient preparation and affordable cost. Finally, the newly-developed similar materials were successfully applied to the excavation seepage model test in the Bahe Tunnel of Xi’an Metro Line 9. The evolution laws of osmotic pressure, surrounding rock stress and internal force of lining were obtained, which facilities to reveal the mechanism of water and sand gushing as well as liner deterioration under the actions of groundwater seepage and excavation disturbance. The material can effectively simulate the granular mixtures, which provides the scientific basis for better selection and configuration of solid-liquid coupling materials.]]></description>
      <pubDate>Fri, 15 Mar 2024 16:35:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/2335928</guid>
    </item>
    <item>
      <title>Reverse-seepage and saturation action anti-corrosion tech (RS-AAT) for corrosion resistance and self-healing of cracked concrete in seawater immersion</title>
      <link>https://trid.trb.org/View/2322926</link>
      <description><![CDATA[Reverse-seepage and Saturation based Action Anti-corrosion Tech (RS-AAT) is a cutting-edge technology that saturates concrete materials and provides anti-hydraulic pressure to offer robust protection against chloride salt-induced corrosion. This study examined the crack repair capability and anti-chloride invasion effect of RS-AAT-treated concrete by experimental and numerical analyses. The results indicated that, under the effect of RS-AAT, the crack healing rate achieved the highest value of 12  % and the total chloride concentration dropped by the largest amount of 51.41 % after 120 days. Under 0.4 MPa water pressure, the surface chloride concentration decreased by the most of 69.42 % and the depth concentration curves of different crack widths approached a variance of 1. Moreover, the crack repair coefficients were introduced to improve the accuracy of numerically simulating the chloride ion migration process in cracked concrete. The findings unequivocally demonstrate that the use of RS-AAT could significantly inhibit chloride ion intrusion into the concrete's protective layer, of which effect was intensified with the increase of reverse osmosis water pressure. Such results provided invaluable insights into enhancing the durability and chloride ion resistance of marine-immersed concrete structures.]]></description>
      <pubDate>Tue, 30 Jan 2024 09:25:38 GMT</pubDate>
      <guid>https://trid.trb.org/View/2322926</guid>
    </item>
    <item>
      <title>Design of Anti-blocking and Anti-seepage shield grouting materials and their performance enhancement mechanism analysis</title>
      <link>https://trid.trb.org/View/2202230</link>
      <description><![CDATA[To solve the current problems of long-distance pumping blockage and poor stability of shield grouting material in the construction of subway tunnels, the authors studied the effects of thickener and water reducing type, dosage, and water-to-binder (W/B) ratio on the workability and mechanical properties of shield grouting materials with high-volume crushed sand and ultrafine powder. The mechanism of thickeners' effects on improving mortar properties was analyzed using the cryo-scanning electron microscopy (Cryo-SEM). The results show that proper compatibility of components and proportion optimization make it possible to prepare high-performance shield grouting materials with excellent anti-blocking and anti-seepage properties. These materials exhibit high fluidity, low pressure bleeding rate, homogeneous distribution of components, and meet the engineering requirements regarding setting time and strength of grouting material. A comparison of the performance of three types of thickening agents reveals that although hydroxypropyl methylcellulose (HPMC) improves the pressure bleeding rate of mortar significantly compared to seaweed gum, it leads to a significant delay in the setting time and a decrease in mortar strength. Welan gum (WG) has a minor impact on grouting materials' setting time and strength, and its water retention performance is similar to that of HPMC. However, WG is expensive and causes significant fluidity loss of slurry over time. On the other hand, seaweed gum demonstrates comprehensive advantages in enhancing various aspects of shield grouting materials, exhibiting good anti-blocking and anti-seepage effects. For its calcium-induced gelation property, seaweed gum forms an orderly screen structure of an “egg-box” shape in the pore liquid, then fills the pores between the screens through the film effect of the gel. Finally, the gels form a “screen-printing-like” overall effect, so that seaweed gum has the three-dimensional space network effect as WG and the film forming effect as that of HPMC, which can significantly improve the stability of the grouting material. Therefore, seaweed gum has almost no adverse impact on the strength of shield grouting material but has a relatively lower price.]]></description>
      <pubDate>Mon, 31 Jul 2023 17:24:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/2202230</guid>
    </item>
    <item>
      <title>The Effects of Measures on Lowering the Phreatic Line within Seasonal Soaking Subgrade</title>
      <link>https://trid.trb.org/View/2000526</link>
      <description><![CDATA[The fluctuation of external water level affects the phreatic line within the seasonal soaking subgrade, which directly relates to subgrade performance. Based on the theory of saturated-unsaturated flow, finite element models of seasonal soaking subgrade were built. Three measures, including low-permeability backfill, slope protection, and incomplete blind drainage, were investigated for lowering the phreatic line under four phases of water level variations. Water fluxes within the subgrade were also analyzed. The results indicated that the combination of slope protection and blind drainage was an optimal method. The water table at subgrade centerline was under the ground surface all the time and the peak water table was reduced up to 42.8%. These findings are applicable for seasonal soaking subgrade to reduce water effects.]]></description>
      <pubDate>Tue, 28 Mar 2023 09:53:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/2000526</guid>
    </item>
    <item>
      <title>Assessing a Sand Clay Liner Material for Protecting Highways and Road Shoulders</title>
      <link>https://trid.trb.org/View/1974633</link>
      <description><![CDATA[The damage and distress caused to highways and roads within areas of high swell potential are of great concern in the design of infrastructure projects. The Subgrade is a significant part of the road structural systems. Variation in moisture content due to seasonal weather fluctuation and flooding could result in harming the road foundation support. This is because the capacity and consistency of the support provided by the subgrade are dependent on the soil type, density, and moisture contents. Different rainfall pattern and intensity from one place to another makes the subgrade response more complicated. The common approach to the water or moisture influence on road structures is to prevent moisture or water from entering the systems. However, in the case of severe flooding, it will not be easy to divert all the flood water away from the road structures. Therefore, efficient protection is required. This study is aimed at assessing clay sand liners of variable mix designs to be constructed as a dressing layer along the shoulder or within the body of the shoulder and extending beyond the foot of the slope. Materials of highly expansive clay from Saudi Arabia were mixed with fine to medium sand at variable proportions to introduce the required protection liners. Characterization tests and hydraulic conductivity tests were performed. Relationship between hydraulic conductivity and clay content was obtained and compared to other studies. Compressibility was obtained from the void ratio and vertical stress relationship. Designs were proposed for specific section geometries and shoulder slopes.]]></description>
      <pubDate>Wed, 22 Feb 2023 09:57:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974633</guid>
    </item>
    <item>
      <title>The Seepage-Destruction Mechanism of Water Inrush Channel of Sandstone Fault Filling Using the EDEM-Fluent Method</title>
      <link>https://trid.trb.org/View/2039890</link>
      <description><![CDATA[By the EDEM-Fluent coupling calculation method, the formation mechanism of the seepage failure water inrush channel and the migration of particles in the sandstone fault filling body are studied. Under the condition of variable hydraulic gradient, the whole seepage process can be divided into three stages: slow seepage stage, sudden seepage stage, and stable seepage stage. In the stage of slow seepage, the mass of lost particles is small. In the stage of sudden seepage, particles are lost on a large scale. In the stable seepage stage, the model is basically in a stable state. During the seepage process, the particles in the outlet zone will move before the particles in the inlet zone under the action of the seepage force. The overall movement trend of particles can be predicted, while the movement trajectory of a single particle is irregular. The change trend of the contact quantity between particles is basically consistent with the change in the quality of the lost particles. Moreover, the change in the contact quantity of particles is caused by the loss of the filler particles.]]></description>
      <pubDate>Thu, 20 Oct 2022 10:23:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/2039890</guid>
    </item>
    <item>
      <title>Ras Al-Khair Dry Dock Seepage Cutoff Wall Design and Construction</title>
      <link>https://trid.trb.org/View/2023555</link>
      <description><![CDATA[The King Salman International Ship Repair and Building Complex, located in Ras Al-Khair, Saudi Arabia, and covering 12 million m², is currently under construction and will be the largest shipyard complex in the world once constructed. The overall project consists of design and construction of three fully equipped dry docks, three piers, and more than a hundred buildings and facilities. The dry docks are constructed in dry within two large temporary construction pits with temporary seepage cutoff walls constructed at pit perimeters. The dock floors were designed to be fully water-pressure-relieved with a sub-floor drainage system provided to prevent the buildup of ground water pressure under the floors. Permanent seepage cutoff walls were designed to limit the amount of water reaching the sub-floor drainage system. This paper provides an overall review of the project and design details of the seepage cutoff walls. Some construction challenges are also discussed in the paper.]]></description>
      <pubDate>Tue, 18 Oct 2022 17:11:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/2023555</guid>
    </item>
    <item>
      <title>Water Intrusion in Base/Subgrade Materials at Bridge Ends</title>
      <link>https://trid.trb.org/View/1584746</link>
      <description><![CDATA[Departments of transportation spend considerable time and money repairing pavement failures that occur in the base or subgrade materials near bridge ends. Investigation of these failures often reveal saturated base/subgrade materials. The objectives of this research were to determine all possible sources for water intrusion, develop methods to recognize in-the-field causes of water collection at bridge approaches, and to develop new repair methods that can be economically implemented in the field to minimize water intrusion or remove water from soils. Research focused on existing bridge approaches, concentrated on maintenance techniques to prevent water intrusion at bridge ends, and included an extensive literature review. Several state transportation agencies were contacted for information on design features such as drainage systems and repair techniques. Researchers surveyed the 25 Texas Department of Transportation (TxDOT) districts to gather observations about major factors contributing to water intrusion and settlement at bridge ends. Four TxDOT districts were visited for field investigations of specific bridges, and one bridge was selected for field testing to determine sources of water intrusion for a recurring seepage problem. Based upon information collected, researchers developed a site assessment technique to evaluate the potential of a particular site to incur water intrusion, and methods to develop optimum repair strategies. Several recommendations resulted including an implementation project plan to examine repair techniques in field trials for comparison.]]></description>
      <pubDate>Wed, 27 Feb 2019 09:39:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/1584746</guid>
    </item>
    <item>
      <title>IFCEE 2018: Innovations in Ground Improvement for Soils, Pavements, and Subgrades</title>
      <link>https://trid.trb.org/View/1559602</link>
      <description><![CDATA[This Geotechnical Special Publication contains 50 peer-reviewed papers on ground improvement for soils, pavement, and subgrades. Topics include: ground improvement and seepage control; bio-based soil improvement; geosynthetic/fiber reinforcement; liquefaction and densification; stone columns, piers, and grouting; and pavements and subgrades. GSP 296 will be of interest to a wide range of geo-professionals, including engineering practitioners, geo-technologists, researchers, contractors, and equipment manufacturers and suppliers.]]></description>
      <pubDate>Tue, 20 Nov 2018 10:12:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/1559602</guid>
    </item>
    <item>
      <title>Simplified Approximation for Seepage Effect on Penetration Resistance of Suction Caissons in Sand</title>
      <link>https://trid.trb.org/View/1499011</link>
      <description><![CDATA[During the installation process of suction caisson in sandy seabed, the applied suction not only produces a downward driving force, but also decreases the penetration resistance to the caisson. In this paper, numerical studies were performed to investigate the characteristics of seepage flow around the caisson as well as its effects on the wall friction and the caisson tip resistance. A simplified approximation method was proposed to predict the reduction of penetration resistance. In particular, for the case of sandy seabed interbedded by a layer of low-permeability soil, the seepage flow will be suppressed with the caisson tip getting closer to the low-permeability layer. The seepage flow around the caisson was first studied, and then a new approximation for the seepage-induced resistance reduction, considering the effect of low-permeability layer, was proposed for the engineering practice.]]></description>
      <pubDate>Wed, 25 Apr 2018 11:15:59 GMT</pubDate>
      <guid>https://trid.trb.org/View/1499011</guid>
    </item>
    <item>
      <title>Behavior of Fiber Reinforced Concrete for Controlling the Rate of Cracking in Canal-Lining</title>
      <link>https://trid.trb.org/View/1485166</link>
      <description><![CDATA[Seepage is a major water loss (20–30%) from the canal as compared to the other forms of water losses. Concrete is commonly used for canal-lining to reduce the seepage loss. Considerable seepage (15–20%) has been observed even in the cement–concrete conventional sections. The performance of canals decreases with an increase in the rate of cracking in concrete canal-lining. The rate of cracking in canal-lining can be reduced by improving the flexure, compressive, and splitting-tensile strengths of concrete. Out of these, splitting-tensile strength of concrete plays a vital role in controlling cracks. The use of fibers for characteristics improvement of concrete is very ancient. Natural fibers include many benefits, like low cost due to its abundance, least health hazards, and flexibility. The use of synthetic fibers as reinforcement in matrix has also attained intentness by reasons of its high strength, less water absorption, and low density in nature. The overall aim of the research program is to explore materials for better performance of canal-lining in terms of reduced water losses by controlling its rate of cracking due to alternate wetting and drying, and due to differential settlement, etc. The purpose of this work is to examine experimental behaviors of jute fiber reinforced concrete (JFRC), nylon fiber reinforced concrete (NFRC), and polypropylene fiber reinforced concrete (PPFRC) for controlling the rate of cracking in canal-lining. For this purpose, the mechanical properties (compressive, splitting-tensile, and flexure strengths, energies, and toughness indices), water absorption, and linear shrinkage of JFRC, NFRC, and PPFRC are determined experimentally as per ASTM standards. The properties of plain concrete (PC) are used as reference. The proportion of 1:3:1.5:0.7 (cement: sand: aggregate: water) is used for PC mix. The mixes of JFRC, NFRC, and PPFRC are manufactured by adding the jute fibers, nylon fibers, and polypropylene fibers, respectively, in the same mix design as that of PC. For production of each type of fiber reinforced composite (FRC), fibers having length of 50 mm are added in concrete by an amount of 5% (by mass of cement). A reduction in compressive properties, and an improvement in splitting-tensile and flexural strengths, water absorption and linear shrinkage is exhibited by FRCs over that of PC. Among the tested FRCs, PPFRC shows better performance. This may ensure to control the rate of cracking in canal-lining, ultimately improving its performance.]]></description>
      <pubDate>Thu, 19 Oct 2017 10:12:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/1485166</guid>
    </item>
    <item>
      <title>Effect of Downward Seepage on Turbulent Flow Characteristics and Bed Morphology Around Bridge Piers</title>
      <link>https://trid.trb.org/View/1460665</link>
      <description><![CDATA[In this work, experimental investigations have been pursued to analyse the influence of downward seepage on the turbulent characteristics of flow and corresponding changes in vortex structure around circular bridge pier in alluvial channel. Experiments were conducted in sand bed channel with circular piers of different sizes for no seepage, 10% seepage and 20% seepage cases. The measurement of turbulent flow statistics such as velocity and Reynolds stresses is found to be negative within the scour hole at upstream of the pier whereas application of downward seepage retards the reversal of the flow causing a decrement in the velocity and Reynolds stresses. Higher Reynolds shear stress prevails at the downstream side because of the production of wake vortices. Contribution of all bursting events to the total Reynolds shear stress production has been observed to increase with downward seepage. The analysis of integral scale suggest that size of eddies increases with seepage, which is responsible for increase in particle mobility. Initially rate of scouring is more which abatements gradually with expanding time as well as with the increased of downward seepage. Presence of downward seepage reduces the depth and length of vortex and shifts towards downstream side of the pier.]]></description>
      <pubDate>Tue, 28 Mar 2017 17:08:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/1460665</guid>
    </item>
    <item>
      <title>A Study on the Strategy of Seepage Leakage Treatment of Highway Tunnels under a Long-Term Groundwater Table</title>
      <link>https://trid.trb.org/View/1417209</link>
      <description><![CDATA[Under the condition of the long-term action of a groundwater table, especially in a karst area, tunnel diseases, especially seepage, leakage and lining deterioration, threaten the safety of traffic and the tunnel structure. These problems appear gradually due to the changing groundwater flow path around tunnels with atmospheric precipitation in the catchment area. Physical and mechanical properties are worse in the surrounding rocks and soils. How to prevent and treat the diseases effectively has become an urgent problem to be solved. A comprehensive strategy, with the example of the Pishuangao Tunnel on the Beijing-Zhuhai Expressway, was adopted by the authors. It was combined with ground surface, surrounding rock and lining treatment, after architectonic geology, hydro- and engineering geology, geophysics and an engineering geological survey,]]></description>
      <pubDate>Mon, 29 Aug 2016 11:14:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/1417209</guid>
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