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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>
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    <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>Service performance of ballastless slab track subjected to mud pumping development and polyurethane injection remediation</title>
      <link>https://trid.trb.org/View/2566407</link>
      <description><![CDATA[Mud pumping induced by frequent train passages causes excessive track vibrations, posing significant safety risks to railway operations. This study investigates the service performance of ballastless slab tracks under various roadbed conditions, spanning from the onset of mud pumping to its remediation, using static and dynamic load tests on a full-scale physical model. The study identifies a three-stage pattern of rainwater infiltration: initial vertical infiltration, subsequent lateral infiltration, and eventual upward saturation. A discriminant formula, incorporating the particle size distribution of roadbed materials, is proposed to predict mud pumping onset. Interestingly, sudden changes in train speed significantly accelerate the initiation of mud pumping, while sustained loading cycles at constant speeds have minimal impact, making train speed control an effective mitigation strategy. The polyurethane injection (PI) remediation method was applied to restore the affected areas. After large loading cycles following the PI remediation, trackbed stiffness and fundamental frequency recovered to 88 % and 100 % of their initial values, respectively. Furthermore, the track structure’s cumulative displacement (2.17 mm) and vibration velocity (84.34 mm/s) remained notably below the specified limits. Field application of the PI remediation also demonstrated a significant reduction in track elevation deviation, confirming the long-term effectiveness of the polyurethane-treated roadbed in mitigating mud pumping deterioration.]]></description>
      <pubDate>Thu, 24 Jul 2025 11:29:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2566407</guid>
    </item>
    <item>
      <title>Study on tire-road air pumping noise characteristics based on computational fluid dynamics (CFD) and acoustic finite element simulation</title>
      <link>https://trid.trb.org/View/2563323</link>
      <description><![CDATA[Air pumping noise is a major source of tire-road noise when vehicles are traveling at high speeds, making it essential to study air pumping noise to reduce overall tire-road noise. However, current indoor and outdoor noise testing methods struggle to effectively isolate pumping noise from overall tire-road noise. Therefore, this study uses computational fluid dynamics (CFD) and acoustic finite element methods to conduct numerical simulations of tire-road air pumping noise, exploring the impact of various tire and road factors on tire-road contact characteristics and air pumping noise. Results indicate that factors such as tire pressure, load, and road texture influence the contact state between the tire and road, which in turn alters air pressure and airflow in the contact area, affecting the air pumping noise. As tire pressure and road texture wavelength increase, air pumping noise gradually intensifies; conversely, as load and road texture depth increase, air pumping noise decreases. Gray correlation analysis shows that tire parameters have a greater impact on air pumping noise than road parameters, with road texture depth having the smallest effect.]]></description>
      <pubDate>Wed, 23 Jul 2025 09:14:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/2563323</guid>
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    <item>
      <title>Pore Water Pressure Behavior in Granular Subbase under Pavement Pumping</title>
      <link>https://trid.trb.org/View/2335250</link>
      <description><![CDATA[Pavement pumping can significantly reduce the overall strength of pavements, even rigid or flexible pavements. The fine contents in the subbase material underneath the pavement slabs move up to the pavement surface through the cracks in the slabs due to pumping, resulting in the erosion of the subbase and decreased structural support. Pumping occurs when water that has accumulated underneath a slab is pressurized when the slab deflects under traffic loading. Therefore, the pore water pressure behavior in the granular subbase is an essential factor in clarifying the pumping mechanism. Model tests were conducted in this study to observe the pore water pressure behavior under various conditions. The model was a small-sized circular road simulator, consisting of a transparent cylindrical soil chamber made of acrylic, a transparent slab, and a rotational wheel loader. The slab had a single artificial joint in the radial direction simulating a pavement crack. The soil chamber had manometers equipped on the side wall to measure the pore water pressure in the ground. The experimental results showed that the excess pore water pressure generated under the load was greater at the leave slab side than at the approach slab side. It was also observed that the excess pore water pressure was larger in the case of a slower traveling speed, which implies that the larger slab deflection under slower loading resulted in larger excess pore water pressure.]]></description>
      <pubDate>Tue, 23 Apr 2024 13:13:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2335250</guid>
    </item>
    <item>
      <title>The Influence of Sand Composition on Railway Track Pumping and Deformation in Winter Period</title>
      <link>https://trid.trb.org/View/1974076</link>
      <description><![CDATA[The current standards for the effective pore diameter in geotextile materials both in Russia and in other countries have been determined by the techniques using natural sands of certain composition. However, particles that fall into geotextiles from railway ballast differ in form from natural sands. Thus, the existing requirements for the diameter of geotextile filtration passages need to be corrected. The calculation methodology for determining the possibility of colmated layers in sands is described. The requirements for the size of geotextile filtration passages preventing them from colmatage and ensuring the preservation of their filtration properties within the required limits throughout the standard service life are presented. In case of non-compliance with the requirements for sands, colmated layers will occur in them, which will lead in pumping.]]></description>
      <pubDate>Tue, 14 Nov 2023 16:52:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974076</guid>
    </item>
    <item>
      <title>Consolidation of multilayered soil with fractional derivative viscoelasticity due to surface loading and internal pumping</title>
      <link>https://trid.trb.org/View/2227575</link>
      <description><![CDATA[Classical Terzaghi’s solution provides a useful tool to predict the one-dimensional consolidation of homogeneous elastic soil layer with fully drained/undrained boundary condition under instantaneous loading. Due to the sedimentation process and complex internal structure, natural soils usually exhibit multilayered inhomogeneity and viscoelastic behavior. In practical cases, the drainage capacity of the boundaries can change with time. Thus, these practical factors should be well in considered for accurate prediction of the consolidation. This paper extends the classical Terzaghi’s solution to multilayered viscoelastic soil with continuous drainage boundaries and subjected to time dependent loading. The fractional derivative Kelvin-Voigt model is used to describe the viscoelasticity of soil. Two loading cases namely surface loading and internal pumping are considered. The consolidation problem is solved by Laplace transform technique and a transfer matrix formulation. Analytical solutions for excess pore water pressure, effective stress and settlement are given. The present solution is general and can reduce to existing solutions available in the literatures. Numerical studies are conducted to investigate the effects of viscoelastic parameters, boundary drainage capacity and loading rate on the consolidation behavior. It is shown that the multilayered soil system with large viscosity coefficient and small fractional order can consolidate fast. For the consolidation due to internal pumping, the drainage parameters have no influence on the consolidation process.]]></description>
      <pubDate>Mon, 28 Aug 2023 17:10:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/2227575</guid>
    </item>
    <item>
      <title>Detection and quantitative evaluation of pumping distress on bridge deck pavement through field and laboratory experiments</title>
      <link>https://trid.trb.org/View/2146650</link>
      <description><![CDATA[Pumping distress refers to the phenomenon of dynamic water entering a pavement, soaking the cement concrete layer to form slurry, and being pumped out of the pavement void under the action of traffic loading. Pumping distress is frequently reported in high temperature and rainy regions, such as Sichuan province in China. Various factors contribute to pumping distress on bridge decks, but most of these factors have merely been subjected to qualitative assessment. The aim of the study is to conduct a comprehensive quantitative analysis through three years of field investigations and laboratory experiments. The field investigations include ground penetrating radar (GPR), pavement permeability tests, skid resistance tests, and drainage facilities surveys. The quantitative analysis of the field and laboratory inspections revealed that the formation reason, deterioration rate, and damage degree of pumping distress were different between the truck and emergency lanes. The occurrence of pumping distresses was significantly related to the uneven construction of the bridge deck leveling layer, compaction segregation, and poor drainage. Additionally, the influence of pavement thickness uniformity on pumping distress was evaluated by incorporating GPR techniques. Failure in the waterproof adhesion layer resulted in the barrier between the cement concrete deck and the asphalt mixture breaking, which allowed alkaline sources to move and transfer to the pavement layer easily. The outcomes of this study can help bridge authorities and construction contractors choose appropriate design and construction measures to prevent pumping distress.]]></description>
      <pubDate>Tue, 23 May 2023 10:08:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/2146650</guid>
    </item>
    <item>
      <title>Mechanism, prevention and remedy of alkali-pumping in new constructed asphalt pavement</title>
      <link>https://trid.trb.org/View/1983929</link>
      <description><![CDATA[The issue of alkali-pumping has emerged in recent years raising concerns on the quality of the newly constructed asphalt pavement. To understand alkali-pumping and its effects, the authors conducted two-year on-site inspection of a pavement and analysed the mineral composition of alkali-pumping. The water permeability, void characteristics, and water stability of the asphalt pavement with and without alkali-pumping were tested and compared. Then, the authors preliminarily analysed the mechanisms. Furthermore, the probability of the alkali-pumping and its control method were analysed. Lastly, 3D ground-penetrating radar was utilised for analysing the relationship between the dielectric constant and the distribution of alkali-pumping. Subsequently, dielectric constant thresholds corresponding to alkali-pumping were established. The results showed that alkali-pumping is caused by the segregation of the pavement and the leakage of alkali elements. Furthermore, the dielectric constants with and without alkali-pumping were significantly different, and their spatial distribution was well correlated with the occurrence of alkali-pumping. Finally, it was determined that asphalt pavements with a dielectric constant smaller than 3.5 are likely to experience alkali-pumping, while those with a dielectric constant between 3.5 and 6.5 are unlikely to experience alkali-pumping, and in those with a dielectric constant greater than 6.5, the probability of alkali-pumping is negligibly small.]]></description>
      <pubDate>Tue, 05 Jul 2022 12:02:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/1983929</guid>
    </item>
    <item>
      <title>Mitigating Pumping in Pavement Shoulder Using Wicking Geotextile: An Experimental Study</title>
      <link>https://trid.trb.org/View/1976295</link>
      <description><![CDATA[Pumping is one of the major factors contributing toward concrete pavement failures, one which reduces the pavement life, affects road safety, and increases maintenance costs. Existing methods such as nonwoven geotextiles used as drainage systems can drain gravitational (free) water under saturated conditions but not the capillary water under an unsaturated conditions. The objective of this study is to explore and identify the feasibility of using a new wicking geotextile for pumping mitigation in pavement shoulder via laboratory tests and field test section monitoring. Laboratory results showed that soil installed with wicking geotextile was noticeably drier than that with a French drain as a drainage system because the wicking geotextile can drain capillary water. Nearly 3?years of field monitoring verified the effectiveness of using wicking geotextile to reduce water content, especially where the pavement was prone to pumping damage. In addition, exposing the edge of the wicking geotextile to the air further noticeably increased its drainage ability.]]></description>
      <pubDate>Tue, 07 Jun 2022 16:13:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/1976295</guid>
    </item>
    <item>
      <title>Faulting development in concrete pavements and overlays</title>
      <link>https://trid.trb.org/View/1746097</link>
      <description><![CDATA[The faulting model currently adopted in the Pavement ME design procedure accounts for the pavement response, climatic conditions, traffic, and erodibility of the base. The same faulting model is applied to all jointed concrete pavements regardless of the pavement structure (conventional concrete pavement, unbonded concrete overlay, bonded concrete overlay, etc.). This implies the pumping mechanism is the same for all pavement structures. It also assumes that the rate of the development of faulting and the maximum faulting that will occur is the same regardless of the pavement structure. The focus of this study is to investigate the mechanisms contributing to the development of voids beneath the slabs and faulting for a range of pavement structures. The results are used to determine the suitability of applying one faulting model to all pavement structures. The focus is directed toward undoweled structures since dowelled joints significantly reduce the potential for the development of faulting. It was found that the development of faulting is delayed, develops at a slower rate, and the magnitude of the faulting tends to be higher in overlays as compared to that in jointed plain concrete pavements. In conclusion, a single faulting model is not suitable for application for all pavement structures.]]></description>
      <pubDate>Mon, 26 Oct 2020 17:54:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/1746097</guid>
    </item>
    <item>
      <title>Implementing an Analytical Framework to Quantify the Magnitude and Rate of Subgrade Pumping in Flexible Pavement</title>
      <link>https://trid.trb.org/View/1688488</link>
      <description><![CDATA[Particle transport in porous media can significantly compromise the serviceability of civil infrastructure. For example, pumping or migration of saturated subgrade soil to pavement subbase, adversely affects the performance of the pavement and leads to its failure. In this study, an analytical framework is implemented to 1) understand mechanisms of pumping, and 2) estimate the amount of subgrade fines migration into subbase under traffic loads. The model is verified using results obtained from experimental investigations previously conducted to quantify the amount of pumping. The experimental tests were conducted using one-third model mobile load simulator (MMLS3), an accelerated pavement testing (APT) device. Results showed that the analytical model provided a reasonable prediction of the amount of fines migration from a saturated pavement subgrade to subbase. The study also revealed that the subgrade pumping and the deposition process is governed by hydraulic condition, erodibility of subgrade, grain size of subgrade, grain size and pore size of subbase, permeability of subbase, and viscosity of pore fluid in the subbase.]]></description>
      <pubDate>Tue, 23 Jun 2020 12:29:06 GMT</pubDate>
      <guid>https://trid.trb.org/View/1688488</guid>
    </item>
    <item>
      <title>Use of Wicking Fabric to Reduce Pavement Pumping</title>
      <link>https://trid.trb.org/View/1688497</link>
      <description><![CDATA[Pumping is among the leading distresses in both flexible and rigid pavement. Pumping is defined as the ejection of water and fine materials of the pavement system under pore water pressure generated by repetitious traffic loading through larger voids or cracks. Pumping can significantly reduce the overall strength of the pavement, clogging the course material and eventually affecting pavement performance. Pumping requires heavy traffic loads, water, fine content in the lower layer, and no fine particles in the upper layer. Methods of limiting pumping include removing water, reducing pore water pressure, and separation of fine content from upper layers. The latter is investigated extensively in the literature. In this study, the reduction of water content as a means to reduce pumping is investigated. The drainage performance of a newly developed geotextile that can drain water both in saturated and unsaturated conditions has been compared to conventional drainage systems being used in pavements. For this purpose, a box filled with a granular pavement base material was instrumented and measurements of volumetric water contents were made to compare the effectiveness of each studied case. Results showed that the drainage ability of the newly developed geotextile is significant, specifically in an unsaturated condition, compared to conventional drainage methods being used in practice.]]></description>
      <pubDate>Mon, 30 Mar 2020 17:48:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/1688497</guid>
    </item>
    <item>
      <title>Field investigation and full-scale model testing of mud pumping and its effect on the dynamic properties of the slab track–subgrade interface</title>
      <link>https://trid.trb.org/View/1640798</link>
      <description><![CDATA[Passenger comfort and safety are the most important aspects in the operation of high-speed railways. Mud pumping is a typical problem that occurs in the slab track and the subgrade interface, which influences passenger comfort and safety. In this paper, various field investigations and a full-scale model of the slab track and the subgrade are presented. The external and internal characteristics of mud pumping in the slab track–subgrade interface and the influence of mud pumping on the dynamic properties of the slab track–subgrade are analyzed. The results show that mud pumping only occurs at the expansion joints in the concrete base of the slab track structure. This happens due to the infiltration of rainwater into the subgrade bed through the cracks in the expansion joints. When the upper layer of the subgrade is kept saturated in the full-scale model, mud pumping is found to occur after 3.0 × 10⁴ loading cycles. The vibration ratio of the subgrade surface to the concrete base gradually increases with continued cyclic loading. In addition, the cumulative settlement of the subgrade increased continuously. After 2.0 × 10⁶ loading cycles, it was found that a large volume of slurry composed of water and fine particles was squeezed out of the subgrade bed, and mud pumping occurred on the surface of the subgrade bed leading to the formation of a mud layer between the concrete base and the subgrade bed, causing a loss of contact between the subgrade bed and the concrete base. This reduces the ability of the subgrade bed to support the slab track structure.]]></description>
      <pubDate>Fri, 30 Aug 2019 15:55:41 GMT</pubDate>
      <guid>https://trid.trb.org/View/1640798</guid>
    </item>
    <item>
      <title>Assessment of Geotextile Effectiveness in Decreasing Subgrade Pumping and Increasing Service Life in Rigid Pavements Using Scaled Model Mobile Load Simulator</title>
      <link>https://trid.trb.org/View/1594103</link>
      <description><![CDATA[Pumping in rigid pavement can be defined as a traffic-induced subgrade soil migration into an overlying subbase layer, and/or redistribution of materials under slabs. Pumping may reduce the service life of pavement. This study aimed to assess the effectiveness of a geotextile layer in reducing the upward migration of subgrade soil particles to subbase and increasing service life in rigid pavements. A one-third scale model mobile load simulator (MMLS3), an accelerated pavement testing (APT) device, was used to simulate the repeated traffic loading on a scaled simulated pavement representing a typical rigid interstate highway. Two tests with identical configurations were conducted, except that a geotextile layer was placed at the interface of subgrade and subbase in one of the tests. In this study, pumping at a rigid pavement joint was investigated. Results of the tests were then compared. Materials used for construction of the scaled pavements were selected such that they represented an in situ stress condition. It was realized that the amount of migration increased with increased number of loading cycles. After 1,000,000 cycles of MMLS3 loading, approximately 70% reduction in the amount of subgrade migration and 52% reduction in the severity of joint faulting were observed when using geotextile at the subgrade-subbase interface of the pavement. This indicated that a geotextile separation layer was significantly effective in mitigating subgrade soil migration and could extend pavement serviceability.]]></description>
      <pubDate>Wed, 24 Apr 2019 09:26:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/1594103</guid>
    </item>
    <item>
      <title>An Investigation of Concrete Pavement Distress on Interstate 78</title>
      <link>https://trid.trb.org/View/1499723</link>
      <description><![CDATA[The concrete pavement on Interstate Route 78, Section 2B has a history of premature and progressive deterioration in the form of faulting, cracking and spalling. This study was undertaken to determine if the pavement distress, particularly the recently accelerated cracking and spalling in the vicinity of transverse joints, resulted from inadequate design of the New Jersey Department of Transportation's standard expansion joint. Based on field and laboratory analyses of excavated pavement-joint specimens and underlying soil layers (subbase and subgrade), it is concluded that the general deterioration of the subject pavement was initiated by the pumping of fines. In particular, it is believed that the pumping phenomenon precipitated spalling by causing wear of the concrete surrounding the free side of the dowels, forming a channel through which pumped incompressibles entered and accumulated in the expansion space. This loss of expansion space resulted in the formation of cracks which subsequently manifested as surface spalls. It is recommended that the present design for the Department's standard Type A expansion joint remain unchanged.]]></description>
      <pubDate>Mon, 02 Apr 2018 12:31:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/1499723</guid>
    </item>
    <item>
      <title>Detection of Voids Underneath Continuously Reinforced Concrete Pavements</title>
      <link>https://trid.trb.org/View/1466854</link>
      <description><![CDATA[The basic assumption in pavement design is that there is full support through-out the length of the pavement. When a void develops, this is not true. This report investigates three methods of detecting voids underneath continuously reinforced concrete pavements. The methods; deflection, pumping, and vibration, are evaluated to find which has the highest probability of successfully detecting voids. The deflection method is shown to be very reliable in predicting voids beneath continuously reinforced concrete pavements (CRCP) and as such a detailed procedure for void detection using this technique has been outlined. The successful detection of such voids, by the method outlined in this report can lead to the repair and subsequent restoration of pavements in which voids have developed. In this way, expensive major rehabilitation of pavements can be prevented.]]></description>
      <pubDate>Tue, 30 May 2017 08:24:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/1466854</guid>
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