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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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    <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>Calculation method for static and seismic active earth pressure on counterweight retaining walls under translation based on two critical slip surfaces</title>
      <link>https://trid.trb.org/View/2423443</link>
      <description><![CDATA[The counterweight retaining wall with polyline wall back is a kind of gravity walls, which can be alternatively used in high embankments. To completely analyze active earth pressure on the polyline back under the wall translation mode, a comprehensive method is proposed based on two planar slip surfaces in the retained soil, an inclined slice method within the frame of limit equilibrium, and the pseudo-static approach. Meanwhile, the two critical slip surfaces include the global and local ones in the soils behind the whole wall and only the upper wall, respectively; and mobilized shear strength coefficients on interslice surfaces are introduced to fully consider the interslice shear forces. Some examples show that the proposed resultant forces on the whole wall are close to the experimental and numerical results generally within 10% error. The dip angle of backfill surface has a significant effect on the two slip surfaces, and the inclination of the lower back mostly influences the global slip surface. The unloading effect of the platform on the lower earth pressure becomes obvious as the upper wall lengthens under a constant height of the whole wall. The magnitude and profile of the seismic earth pressure on the polyline back are greatly influenced by the seismic coefficients.]]></description>
      <pubDate>Wed, 25 Sep 2024 09:22:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/2423443</guid>
    </item>
    <item>
      <title>Measurement and Analysis of the Performance of the Pvp-20 Slip Detection Device</title>
      <link>https://trid.trb.org/View/2166459</link>
      <description><![CDATA[One of the most critical elements ensuring the proper operation of locomotives are devices that detect and eliminate slipping, especially during the start-up of the locomotive in difficult operating conditions. Various types of slip control systems and methods are used on traction vehicles, depending on the design of a given locomotive and the assumptions made related to the functionality of a given solution. This article describes the PVP-20 type slip detection device used in many older electric locomotives. A proprietary measuring system was developed, enabling it to be connected to the locomotive circuit, to perform measurements in conditions of large disturbances and high voltages prevailing on the electric locomotive. Using this measuring system, the PVP-20 device was tested under operating conditions for the ability to detect slips. It has been shown that the described device is highly insensitive. Hence, the authors propose their concept for solving this problem.]]></description>
      <pubDate>Thu, 25 May 2023 17:41:09 GMT</pubDate>
      <guid>https://trid.trb.org/View/2166459</guid>
    </item>
    <item>
      <title>Initiation of 2014 Oso Landslide Using 3D Slope Stability Analyses: Effect of Infiltration</title>
      <link>https://trid.trb.org/View/2113260</link>
      <description><![CDATA[March 2014 Oso landslide, which demolished Steelhead Haven Community near Oso, Washington, is the deadliest in US history. Several factors have been suggested for the initiation of this landslide by various researchers including, the heavy rainfall before the landslide, timber harvesting on the upper plateau, river erosion at the slope toe, groundwater rise due to rainfall infiltration, and irregular 3D topography of the slope. This study utilizes 3D limit equilibrium and 3D finite element seepage analyses to investigate the effect of rainfall infiltration in the 7.5 acres timber harvest area at the top of the slope as well as potential changes of groundwater elevation on the initiation of 2014 Oso landslide. To achieve these objectives, the infiltration rate was varied in the harvested area to investigate its effect on the first phase initiation. Also, two potential groundwater levels were examined to assess the sensitivity of the first phase slide mass to changes in groundwater conditions. The 3D factor of safety for the critical slip surfaces was obtained for the two groundwater levels using two conventional limit equilibrium methods. The safety factor for the critical slip surface is slightly different for the first and second groundwater levels. The difference is such small that it can be concluded that a reasonable rise in groundwater level would not have been the triggering factor for the 2014 Oso landslide. The impacts of other potential factors such as shear strength reductions of upper layers due to the rainfall infiltration, timber harvesting, and/or 3D slope geometry effects appear to have been more influential in the initiation of the landslide.]]></description>
      <pubDate>Mon, 10 Apr 2023 11:58:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/2113260</guid>
    </item>
    <item>
      <title>Effect of spatial variability of soil properties and geostatistical conditional simulation on reliability characteristics and critical slip surfaces of soil slopes</title>
      <link>https://trid.trb.org/View/2100429</link>
      <description><![CDATA[Evaluation of the stability and determination of the Critical Slip Surface (CSS) of soil slopes are salient topics in geotechnical engineering. On the other hand, the stability and CSS are not only affected by soil heterogeneity but also by the boreholes’ location and method of predicting soil parameters in the domain of analysis. The unconditional simulation in which known data and its location are not incorporated may lead to results far from reality. Moreover, in some conditional simulations, the borehole data are directly mapped into the analysis section without taking the location of the known data into account, which can either overestimate or underestimate the stability of the slope. In the current study, the Finite Element Method (FEM) is coupled with the geostatistical method to evaluate the reliability characteristics and CSS distribution with consideration of the known data, location of boreholes, uncertainty of surcharge load, and soil heterogeneity. The results of a real case demonstrate that in comparison to the unconditional simulation, utilizing the conditional simulation improves the distribution of Factor of Safety (FS) by up to 14% while decreasing the related standard deviation by 4% to 40%. Moreover, conditional simulation offers a significant reduction in uncertainty of the slip surface and unsafe distance from the edge of the slope. Besides, it is concluded that soil heterogeneity has a major impact on CSS distribution and induces the local CSS, which cannot occur on a homogeneous slope.]]></description>
      <pubDate>Wed, 22 Feb 2023 09:57:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/2100429</guid>
    </item>
    <item>
      <title>Shear band propagation and mechanical behaviours of landslides under top loading</title>
      <link>https://trid.trb.org/View/2050355</link>
      <description><![CDATA[The configuration of slip surface is conventionally regarded as a key characteristic to distinguish slope failure modes that are embedded in the limited equilibrium method and the bearing capacity theories. However, few studies indicated that a different way of propagating a slip surface with the same configuration might affect the mechanical behaviour and failure mode of the slope. In this paper, the mechanical behaviour is studied in two slopes that have a similar configuration of slip surface with different processes of shear band evolution. Advances in transparent soil technology allow the non-intrusive observation of shear band development in the laboratory slope models. This paper presents shear band development inside slopes using the transparent soil technique and then analyse the mechanical behaviour via the discrete element method (DEM). In order to reproduce the laboratory results, the real shape of transparent soil particles is used in the DEM model, and the microscopic parameters are calibrated by response surface methodology (RSM). The mechanical parameters such as movement, stress, void ratio and energy dissipation are measured in different stages of shear band evolution and are measured in four regions: the weak plane, the shear band, the slope mass above the slip surface, and the slope mass below the slip surface. This paper presents the role of shear band propagation in the mechanical behaviour of slope and discusses the possibility of monitoring the mechanical behaviour of slope to predict the coalescence of slip surface.]]></description>
      <pubDate>Fri, 23 Dec 2022 14:07:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/2050355</guid>
    </item>
    <item>
      <title>Experimental Study on Settlement of Backfill in Integral Bridge Abutments Induced by Seasonal Temperature Changes</title>
      <link>https://trid.trb.org/View/1853310</link>
      <description><![CDATA[To reduce construction cost, minimize long-term maintenance of girder beams, and prevent water infiltration-induced erosion problems at expansion joints, integral bridge abutments have been increasingly used in the practice. This type of abutments is subjected to passive earth pressures when bridge girders expand at high temperatures. When the bridge girders contract at low temperatures, backfill materials tend to move downward, inducing settlement of the backfill and creating “the bump at the end of the bridge” problem. This problem becomes progressively worse over time. Some research has investigated the mechanisms associated with this problem; however, more research is needed to further understand these mechanisms, especially under controlled conditions. This paper presents four physical model tests conducted to investigate the mechanisms and effects of seasonal temperature changes on the movements at the bottom of the abutment and the settlement on the backfill. In these tests, concrete blocks were tied together using three thread rods to simulate the abutment, while the Kansas River sand was used as the backfill material and compacted in lifts. A manual jack was used to control cyclic movements of the abutment to simulate the seasonal temperature changes. The movements of the abutment and the settlement on the backfill were monitored during each test. The experimental results showed that the influences of the abutment movement on the settlement of the backfill decreased with the distance from the back of the abutment but increased with the number of cycles. When the abutment toe was allowed to have more movement during cyclic movement, a triangular sliding wedge more likely formed, thus causing a settlement trough on the backfill. The magnitude of the horizontal displacement and the number of movement cycles of the abutment could affect the formation of a slip surface between an active sliding wedge and a stable soil. Larger abutment displacement required fewer number of movement cycles for the slip surface to occur, and the formation of the slip surface changed the settlement profile.]]></description>
      <pubDate>Wed, 09 Jun 2021 17:19:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/1853310</guid>
    </item>
    <item>
      <title>A new paradigm to explain the development of instability rutting in asphalt pavements</title>
      <link>https://trid.trb.org/View/1741281</link>
      <description><![CDATA[Using the most sophisticated models, rutting in asphalt pavements is currently explained as the result of the accumulation of vertical compressive strain due to air void reduction (i.e. densification) and lateral dilation of the asphalt mixture induced by repeated traffic loads, mainly during warmer seasons. However, instability rutting of asphalt mixture may not be fully explained by volume change alone. The primary objective of this study was to identify a potential mechanism of instability rutting consistent with transverse profiles observed in asphalt pavement. A finite element model of a radial truck tyre on a flexible pavement structure showed the existence of potential slip planes defined by a series of contiguous points along which the direction of maximum shear stress was aligned. Stress states along potential slip planes coupled high shear with low confinement, or even tension. The criticality of these stress states was studied by comparing shear stress to shear strength. It was found that stress states induced by a radial tyre, in addition to the reduction in asphalt mixture shear strength caused by repeated traffic loads and higher temperatures, may promote the development of a global shear plane under the tyre edge along which slip occurs. Rotation of a slipped zone, rather than volume change alone, may explain the development of ruts and lateral humps along the wheel path in agreement with transverse profiles observed in asphalt pavement.]]></description>
      <pubDate>Tue, 13 Oct 2020 09:17:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/1741281</guid>
    </item>
    <item>
      <title>New analytical solutions for shallow cohesive soils overlying trench voids under various slip surfaces</title>
      <link>https://trid.trb.org/View/1724355</link>
      <description><![CDATA[This paper investigates the effects of cover ratio and soil strength parameters (cohesion and friction angle) on the failure mechanisms of cohesive soils overlying trench voids using trapdoor technique. Adaptive finite element limit analyses (AFELA) were conducted to study the failure mechanisms of trapdoors covered with soils of different thicknesses, cohesions and friction angles. It was found that slip surfaces in the cover soil could be in the shape of vertical, trapezoid, spiral or arching, depending on the combination of soil strength parameters and cover ratio. Analytical solutions under various slip surfaces, considering major principal stress trajectories to describe load transfer paths, are further proposed to study the load transfer mechanisms in shallowly embedded trapdoors. The solutions in terms of arching ratios and lateral earth pressure coefficients were validated against the results of previously reported laboratory tests and AFELA. The results show that the modified earth pressure coefficient is greater than 1.0 due to the consideration of the major principal stress trajectory. The vertical stresses acting on trapdoors are in an inverted parabolic distribution, which are lower in the middle. The arching ratio decreases with increasing soil cohesion, friction angle and cover ratio. For cohesionless soils, the arching ratio decreases as the surcharge loading ratio increases, but for cohesive soils, the arching ratio increases with increasing surcharge loading ratios.]]></description>
      <pubDate>Thu, 27 Aug 2020 10:16:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/1724355</guid>
    </item>
    <item>
      <title>Limit Equilibrium Stability Analysis of Layered Slopes: A Generalized Approach</title>
      <link>https://trid.trb.org/View/1566673</link>
      <description><![CDATA[Traditionally, application of the conventional logarithmic spiral in limit equilibrium (LE) analyses has been limited to homogenous materials. Herein, a modification of the conventional logarithmic spiral LE approach is proposed to account for transitions in soil conditions and provide insight into the internal statics associated with this approach, termed the compound log-spiral (CLS). Comparing both factor of safety (FS) and failure surfaces for a range of frictional strength combinations, the CLS approach demonstrates good agreement with results derived from both generalized, commercially available rigorous LE analyses and finite element analyses. The utility of the CLS method is further demonstrated through an example where the stability of a heavily stratified seacliff is considered. The proposed method satisfies equilibrium at a limit state without resorting to internal statistical assumptions associated with traditional LE approaches. Furthermore, it enables the explicit determination of internal statics, such as inter-slice shear forces, inter-slice normal forces, inter-slice angle, line of thrust, and normal stress distributions, which is a less-than-trivial task for the complex slip surface geometry realized in heterogeneous slope failures. Subsequently, the reasonableness of results could be assessed.]]></description>
      <pubDate>Tue, 22 Jan 2019 11:39:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/1566673</guid>
    </item>
    <item>
      <title>Using Reliability Theory to Assess the Stability and Prolong the Design Life of Existing Engineered Slopes</title>
      <link>https://trid.trb.org/View/1557894</link>
      <description><![CDATA[Modern engineered slopes are designed to exceed certain safety targets set out in design codes. This is in stark contrast to earthen infrastructure inherited from the 18th century which typically was constructed in a haphazard manner without design. This infrastructure seldom meets modern deterministic guidelines yet clearly exhibits some degree of safety, as a failure has not occurred in the intervening years. This paper highlights the use of reliability theory for evaluating the stability of existing engineered slopes. A comprehensive review of geotechnical uncertainty and existing reliability based techniques are outlined. Furthermore, the paper highlights the issue of finding the critical slip surface and gives a brief summary of the current state of the art. Finally a case study of an Irish railway embankment is presented and both a deterministic and reliability analysis is performed on it highlighting the benefits of probabilistic methods over traditional techniques.]]></description>
      <pubDate>Thu, 27 Dec 2018 10:56:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/1557894</guid>
    </item>
    <item>
      <title>Upper Bound of Seismic Active Earth Pressure on Gravity Retaining Wall with Limited Backfill Width</title>
      <link>https://trid.trb.org/View/1509775</link>
      <description><![CDATA[The failure mechanisms of backfill with limited width that is subjected to a co-application of earthquake force and surcharge formed by single and double wedges, respectively, were introduced to address the active earth pressure acting on gravity walls. An analytic model that is applicable to general cases of tilt walls with frictional backs and inclined ground surfaces was established by incorporating the quasi-static Mononobe-Okabe method and upper bound limit analysis. The reasonability and effectiveness of this technique were verified and supported by a comparison with results from reported laboratory model tests. A sample case analysis revealed a nonlinear distribution of active earth pressure on a gravity wall with limited backfill width. Coulomb’s solution and three other published methods tended to overestimate the earth pressure measured in the laboratory more significantly than the proposed method did when the width of the backfill was reduced to a critical threshold. The superiority of this suggested technique increased with the shrinkage of backfill width. Moreover, the ascending horizon seismic coefficient k and surcharge q mobilized an increasing active thrust on the wall while easing and enlarging the crack angle of the slip surface, respectively.]]></description>
      <pubDate>Mon, 25 Jun 2018 13:49:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1509775</guid>
    </item>
    <item>
      <title>Assessment of Slope Stability on the Road</title>
      <link>https://trid.trb.org/View/1469615</link>
      <description><![CDATA[The paper deals with the assessment of slope stability on the road II / 595 near the village Zlatno before and after the landslide caused by floods in 2010. For proposal for a comprehensive assessment and possible remedial action is necessary to know the geological conditions and choose the appropriate method for to assess slope stability. The calculation of factor of safety was made using GEO 5 software. The critical factors of safety have been determined by Petterson and Sarma Methods. After finding the most unfavorable slip surface has been made a proposal of remediation measures. The paper presents various solutions to ensure slope stability of the road. The most appropriate remedial action is Variant III - reinforced slope, because he had a greater factor of safety.]]></description>
      <pubDate>Wed, 28 Jun 2017 14:40:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/1469615</guid>
    </item>
    <item>
      <title>Displacement Measurement of Slow Moving Landslides using Sub-mm LIDAR Scanning</title>
      <link>https://trid.trb.org/View/1459231</link>
      <description><![CDATA[Most landslides do not happen instantly. Often there is advanced warning of imminent catastrophic failure. Because of creep phenomenon, slow slip movement has a steady state phase during which the movement, although small, can be observed and recorded. Slides in critical areas are usually recognized during this steady state phase. In those slopes that fail catastrophically, evidence of small movement is usually recognizable early on before the catastrophic failure begins. Terrestrial LIDAR (Light Detection And Ranging) scanners are capable of creating a 3-D map of a slope measuring up to a million data points per second at a single point accuracy of 6 mm. However displacement measurements over time are easily dwarfed by the growth and decay of vegetation cover. In addition, 6 mm accuracy is not enough to measure slow moving landslides. The authors have solved both problems by mounting spherical targets on rigid rods driven into the ground. The spherical targets have been demonstrated to have a position measurement accuracy of 0.3 mm. The rods place the targets above the vegetation. In addition, the use of two spherical targets on each rod is used to measure rotation of the target rods, thus giving insight into the nature of the below grade failure Testing on an active highway site in Branson Missouri, scanned repeatedly over 2014-2015, has shown the feasibility of this method, measuring total displacements of up to 75 mm over that period, and revealing also the directions of movement and information on the subsurface slide surface.]]></description>
      <pubDate>Mon, 27 Mar 2017 09:35:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/1459231</guid>
    </item>
    <item>
      <title>Embankment Design Method Combining Limit-State Approach with Stress-Path Application</title>
      <link>https://trid.trb.org/View/1423130</link>
      <description><![CDATA[A rational design method for embankments on soft soils that takes care of both bearing capacity and stability mechanisms is proposed in this paper. Two types of embankment-construction techniques are used on soft soils: a single-stage construction technique for quickly constructing relatively low-height embankments and a staged-construction technique for constructing high embankments. In this paper, a limit-equilibrium approach is used to estimate the critical slip-surface depth that is assumed to be the bottom line of a possible collapse mechanism under undrained loading conditions corresponding to single-stage construction. In contrast, to design a stage-constructed embankment on soft soils, both undrained and drained conditions must be taken into account. The proposed method can address this behavior and therefore is applicable to embankments constructed in either a single stage or multiple stages. The staged-construction technique, however, necessitates adding the tool of stress-path application to the method to consider both undrained and drained behaviors. This is a property that is not found in limit-state approaches, and it gives the proposed method the capacity to follow and interpret changing stress-strain states and their influence on mobilized strength states.]]></description>
      <pubDate>Wed, 21 Sep 2016 14:45:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/1423130</guid>
    </item>
    <item>
      <title>Multi-modal Reliability Analysis of Slope Stability</title>
      <link>https://trid.trb.org/View/1414111</link>
      <description><![CDATA[Probabilistic slope stability analysis typically requires an optimisation technique to locate the most probable slip surface. However, for many slopes particularly those containing many different soil layers or benches several distinct critical slip surfaces may exist. Furthermore, in large slopes these critical slip surfaces may be located at significant distances from each other. In such circumstances, finding and rehabilitating the most probable failure surface is of little merit, as rehabilitating that surface does not improve the safety of the slope as a whole. Unfortunately, existing slip surface search techniques were developed to converge on one global minimum. Therefore, to implement such methods to evaluate the stability of a slope with multiple failure mechanisms requires the user to define probable slip locations prior to calculation. This requires extensive engineering experience and places undue responsibility on the engineer in question. This paper proposes the use of a locally informed particle swarm optimisation method which is able to simultaneously converge to multiple critical slip surfaces. This optimisation model when combined with a reliability analysis is able to define all areas of concern within a slope. A case study of a railway slope is presented which highlights the benefits of the model over single objective optimisation models. The approach is of particular benefit when evaluating the stability of large existing slopes with complicated stratigraphy as these slopes are likely to contain multiple viable slip surfaces.]]></description>
      <pubDate>Mon, 01 Aug 2016 18:32:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/1414111</guid>
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