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    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>Impact of Earthworks on the Quality of Unpaved Roads in Côte d’Ivoire</title>
      <link>https://trid.trb.org/View/2668467</link>
      <description><![CDATA[Earthen roads, in the general sense, make up over 90% of the road network in Côte d’Ivoire (AGEROUTE CI, 2024), as in most West African countries. Although these roads typically carry low traffic volumes, they play a crucial role in opening up rural areas and transporting agricultural products. As such, their socio-economic importance should not be underestimated.]]></description>
      <pubDate>Tue, 26 May 2026 09:41:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/2668467</guid>
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    <item>
      <title>Influence of Temperature and Soil Thermal Expansion on Cracking of Dirt Road Surface During Seasonal Freezing</title>
      <link>https://trid.trb.org/View/1972879</link>
      <description><![CDATA[Low-temperature cracks reduce the road surfaces quality, increase the cost of their repair. This problem is relevant in the regions with seasonal soil freezing. Analysis of the literature showed that, despite the large research work, the multidisciplinary problem of low-temperature cracking requires further research. In the present work, the object of study is a two-layer structure as a model of a straight section (segment) of an unpaved highway in the stage of seasonal freezing. Subject of research: the conditions for frost cracking in the upper layer of the road during seasonal freezing. Objective: to simulate the conditions for transverse cracking in the upper layer during seasonal freezing of the dirt road, taking into account the influence of temperature on the coefficient of thermal expansion. The paper presents a mathematical model of the frost cracks formation. The results of the modeling are consistent with data known in the literature. From a practical point of view, the results can be used to predict the state of logging roads at the stage of soil freezing in the off-season periods.]]></description>
      <pubDate>Fri, 01 Nov 2024 08:50:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/1972879</guid>
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    <item>
      <title>Exploration of robust and intelligent navigation algorithms to ensure off-road autonomous vehicle mobility</title>
      <link>https://trid.trb.org/View/2403994</link>
      <description><![CDATA[The combat capabilities development command (DEVCOM) ground vehicle systems center (GVSC) is supporting unmanned ground vehicle (UGV) development. Past experimentations of a military UGV demonstrated that its autonomous mode performed worse than the tele-operated mode. To address this, a systematic investigation into path planners for military vehicles in off-road environments was executed. A UGV simulator was used to evaluate vehicle and planner performance through a range of obstacle avoidance scenarios in deformable soil to capture the effects of vehicle-terrain interactions across multiple soil types. Monte Carlo methods were used to evaluate the robustness of five path planners ranging from classical to state-of-the-art planners, with normally-distributed variability in environmental and vehicle initial conditions. After running thousands of simulations, results show how each algorithm compares to one another in several key metrics including overall success rates. These results will help inform decisions in future military UGV path planner selection.]]></description>
      <pubDate>Tue, 30 Jul 2024 14:35:54 GMT</pubDate>
      <guid>https://trid.trb.org/View/2403994</guid>
    </item>
    <item>
      <title>Research on the influence of heavy-duty tracked vehicles parameters on steering driving process</title>
      <link>https://trid.trb.org/View/2350662</link>
      <description><![CDATA[As an important part of the heavy-duty tracked vehicle, the position and posture of crawler travelling device have a certain impact on the vehicle performance. The Bekker soil sinking theory is used in this study to create the heavy-duty tracked vehicle dynamics analysis model under turning conditions on soft soil roads. The effects of working arm position, turning radius R, track grounding width-length ratio b/L and track center distance B on vehicle driving force, driving power, and steering resistance moment were investigated using a heavy-duty vehicle as an example. Track sliding and ground shear deformation were taken into consideration. The findings demonstrate that when the turning radius R is close to B/2, the driving power is almost 0 and the inside steering resisting moment and driving force are concentrated. When R = B/2, the vehicle is in the unilateral power steering. What's more, the study can provide theoretical support for heavy tracked vehicles design.]]></description>
      <pubDate>Wed, 15 May 2024 15:27:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/2350662</guid>
    </item>
    <item>
      <title>Intelligent Transportation Systems in Developing Countries: Challenges and Prospects</title>
      <link>https://trid.trb.org/View/2267124</link>
      <description><![CDATA[Developed countries have paved the way for the implementation of intelligent transport systems (ITS) to improve the safety, efficiency, and environmental impact of transport. With developing countries entering the fray, the question is: Is ITS as implemented in developed countries relevant to developing countries? This research question is discussed in this paper for the case of sub-Saharan countries that are among the poorest countries worldwide. To this end, the paper outlines the main differences in transportation scenarios between developed and sub-Saharan countries, and then considering the main constraints of sub-Saharan countries, a guide towards an affordable intelligent transportation system in these countries is discussed. Finally, the paper proposes two main novel ideas for the deployment of intelligent transport systems on dirt roads.]]></description>
      <pubDate>Mon, 23 Oct 2023 08:51:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/2267124</guid>
    </item>
    <item>
      <title>Integrating biomechanics with stakeholder perspectives to inform safety in grassroots dirt track racing</title>
      <link>https://trid.trb.org/View/2227878</link>
      <description><![CDATA[Grassroots dirt track racing is a foundational part of motorsports with a high risk of severe injury. This study aimed to gather perspectives and experiences of motorsports drivers surrounding safety and head acceleration events experienced during grassroots dirt track racing to inform strategies to improve driver safety. Thirteen drivers (n=9 who primarily race on dirt tracks; n=4 who primarily race on pavement tracks) with prior dirt track racing experience participated in separate, group-specific focus groups and/or one-on-one interviews where video, simulations of head motion, and head acceleration data were shared. Peak kinematics of laps and crash contact scenarios were recorded, and head perturbations (i.e., deviations in head motion relative to its moving-average trajectory) were quantified for each lap and presented through guided discussion. Responses were summarized using Rapid Assessment Process. Audio recordings and field notes were collected from focus groups and interviews and analyzed across 25 domains. Drivers described dirt track racing as short, fast bursts of racing. Benefits of dirt track racing for driver development were described, including learning car control. Drivers acknowledged risks of racing and expressed confidence in safety equipment but identified areas for improvement. Drivers observed lateral bouncing of the head in video and simulations but recognized that such motions were not noticed while racing. Track conditions and track type were identified as factors influencing head perturbations. Mean PLA (5.5 g) and PRV (3.07 rad/s) of perturbations experienced during racing laps and perturbation frequencies of 5 and 7 perturbations per second were reported. Generally, drivers accurately estimated the head acceleration magnitudes but were surprised by the frequency and maximum magnitude of perturbations. Maximum perturbation magnitudes (26.8 g and 19.0 rad/s) were attributed to hitting a “rut” in the dirt. Drivers described sudden stops, vertical loads due to landing from a large height, and impacts to the vehicle frame as crash events they physically feel the most. Summary statistics for crashes (medians = 7.30 g, 6.94 rad/s) were reported. Typical impact magnitudes measured in other sports (e.g., football) were provided for context. Upon reviewing the biomechanics, drivers were surprised that crash accelerations were relatively low compared to other contact/collision sports. Pavement drivers noted limited safety features in dirt track racing compared to pavement, including rigidity of vehicle frames, seat structure, seatbelt integration, and lack of oversight from sanctioning bodies. Most drivers felt seat inserts and head and neck restraints are important for injury prevention; however, usage of seat inserts and preferred head and neck restraint system differed among drivers. Drivers described their perspectives and experiences related to safety and identified strategies to improve safety in grassroots dirt track racing. Drivers expressed support for future safety research.]]></description>
      <pubDate>Thu, 24 Aug 2023 09:30:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/2227878</guid>
    </item>
    <item>
      <title>Drivable Dirt Road Region Identification Using Image and Point Cloud Semantic Segmentation Fusion</title>
      <link>https://trid.trb.org/View/2006002</link>
      <description><![CDATA[Driving scene understanding is an essential technique for realizing autonomous driving. Although many large-scale datasets for autonomous driving have enabled studies in terms of driving scene understanding, unpaved dirt roads have not been considered as their target driving environment. Drivable region identification is important in dirt roads to prevent damage to the vehicle and passengers. Semantic segmentation of camera images and lidar point clouds have been used to recognize the environment around an autonomous vehicle. The road and objects are recognized by classifying image pixels and point clouds into semantic classes. In this study, the authors introduce a perception method for drivable region identification on dirt roads through fusion of image and point cloud semantic segmentation. The approach includes an image semantic segmentation algorithm and a point cloud semantic segmentation algorithm, which the authors combine into a bird’s-eye-view grid map format. To transform the point-wise drivable region identification results into the area-wise information, the authors adopt the alphashape algorithm. Speed improvements are made by using small proportion of drivable points, and the accuracy degradation is compensated by accumulating the perception results along the time.]]></description>
      <pubDate>Thu, 25 May 2023 13:31:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2006002</guid>
    </item>
    <item>
      <title>Pilot characterization of head kinematics in grassroots dirt track racing</title>
      <link>https://trid.trb.org/View/2096239</link>
      <description><![CDATA[ObjectiveThe objective of this study was to utilize an instrumented mouthpiece sensor to characterize head kinematics experienced by grassroots dirt track race car drivers.MethodsFour dirt track race car drivers (ages 16–19) were instrumented with custom mouthpiece sensors capable of accurately measuring head motion during racing. Sensors were deployed before races and recorded tri-axial linear acceleration and rotational velocity for approximately 10?min at 200?Hz. Film review was performed to identify data associated with racing laps. For each lap, moving average kinematics were computed and subtracted from the head motion signals to obtain ‘adjusted’ head motion accounting for lower frequency variance due to periodic motion around the track. From adjusted data, linear and angular head perturbations (i.e., deviations from moving average) were extracted using a custom algorithm.ResultsData was collected during 400 driver-races. A total of 2438 laps were segmented from mouthpiece recordings. The median (95th percentile) peak linear acceleration, rotational velocity, and rotational acceleration of all laps were 5.33 (8.28) g, 2.89 (4.60) rad/s, and 179 (310) rad/s2, respectively. Angular perturbations occurred most frequently about the anterior-posterior axis (median lap frequency = 6.39?Hz); whereas linear perturbations occurred most frequently in the inferior-superior direction (7.96?Hz). Nine crash events were recorded by the mouthpiece sensors. The median (95th percentile) peak head kinematics of these events were 13.4 (36.6) g, 9.67 (21.9) rad/s, and 630 (1330) rad/s2.ConclusionsMouthpiece sensors can be used to measure head kinematics during active racing. Laps, head perturbations, and crashes may be useful units of observation to describe typical head kinematic exposure experienced by drivers while racing. Subsequent research is needed to understand the associations between repetitive racing exposure and neurological function. Higher magnitude events (i.e., crashes) are not uncommon and may result in concussion or more severe injury. Results represent novel characterizations of head kinematic exposure experienced in a dirt track racing environment. This information may inform evidence-based strategies (e.g., vehicle/seat design) to improve driver safety.]]></description>
      <pubDate>Tue, 14 Feb 2023 09:29:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/2096239</guid>
    </item>
    <item>
      <title>Thermal storage under an earthen roadway embankment over a permafrost region</title>
      <link>https://trid.trb.org/View/2083952</link>
      <description><![CDATA[Building roadways in permafrost regions is always challenged because both roadway construction and global warming can induce the warming of the underlying soils. A group of permafrost cooling techniques has been employed to cool the embankment, with the focus on dropping the temperature of the underlying permafrost. To this end, understanding the thermal storage in the underlying soils after the embankment construction is critical to adopt the right techniques to drain the soils' heat at the right place. While the non-linear variation of heat absorption with depth in the permafrost under the embankment has been well documented, it remains unknown how to describe this situation mathematically. In this study, the authors innovatively propose a scalar ∆E to characterize the thermal storage of the soils under an earthen embankment over a permafrost region. It is found that immediately after the embankment was built, the soils at 0–3 m depth are cooled down while those at 3–6 m depth are warmed up. However, the temperature variations of these soils, in shape and in trend, are different from the thermal storage of the soils. The profile of temperature variation versus depth changes continuously, while the profile of thermal storage versus depth varies abruptly at the interfaces of soil layers. The reason is that most heat entering the permafrost stratum is stored in water-rich soils while a limited heat is deposited in water-poor soils. This finding suggests that permafrost cooling techniques shall be considered to drain the thermal storage in the water-rich soils primarily.]]></description>
      <pubDate>Tue, 24 Jan 2023 09:31:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/2083952</guid>
    </item>
    <item>
      <title>Developing an analytical model for prediction of tyre rolling resistance on moist soils</title>
      <link>https://trid.trb.org/View/2065601</link>
      <description><![CDATA[This paper presents a finite element analysis-smoothed particle hydrodynamics (FEA-SPH) technique to predict the rolling resistance of an agricultural tire over moist soils. Firstly, dry clay-loam soil is modelled using hydrodynamic elastic-plastic materials and the water behavior is captured using the Murnaghan equation of state. Then, to simulate moist soil, water layers are added to the dry soil surface. Soil calibration is performed based on experimental data using a bevameter and through the direct shear tests under similar operating conditions. A free-rolling bias-ply tire (size 8.25-16) employed for the experiments was modelled using the FEA method. The interface contact between tire and soil is described based on a node-symmetric node-to-segment contact with edge treatment. The obtained simulation results for rolling resistance account for different levels of soil moisture, traffic and vertical load. Finally, the proposed model is validated using experimental data obtained from a single-wheel tester in the controlled test condition.]]></description>
      <pubDate>Wed, 14 Dec 2022 09:21:22 GMT</pubDate>
      <guid>https://trid.trb.org/View/2065601</guid>
    </item>
    <item>
      <title>Computational Analysis and Decomposition of the “Vehicle-Terrain” System for Off-Road Areas</title>
      <link>https://trid.trb.org/View/1910283</link>
      <description><![CDATA[The study clearly demonstrates the components features of the road-trains heavy trucks during their operation in off-road conditions. In particular, the methodology of road trains cross-country capacity estimates. Calculation of vehicle cross-country capacity, depending on the purpose of the calculation and features of the solved practical task, uses many indicators that are advisable to streamline the hierarchical level of the system to which certain estimated patency indicators include. The author has considered the systems of the following levels: single wheel-soil, vehicle-soil, vehicle-terrain, driver-vehicle-terrain. The lower-level system wheel-soil is basic for a higher hierarchical level system and is considered in more detail by the author in this work. The current presentation of the calculation techniques based on various models of wheel interaction with the soil and various assumptions about the properties of the wheel and soil are considered.]]></description>
      <pubDate>Fri, 18 Mar 2022 12:17:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/1910283</guid>
    </item>
    <item>
      <title>Review of Methods for Calculating the Cross-Country Ability of Heavy Road Trains in Off-Road Conditions</title>
      <link>https://trid.trb.org/View/1910282</link>
      <description><![CDATA[Currently, a variety of calculation methods have been developed based on various models of wheel-soil interaction and various assumptions about the properties of wheel and soil. This refers to the design features of tires, the kinematic and power parameters of the rolling mode, the type and condition of the soil, as well as the design features of road trains. In this work the author has considered a number of methods for assessing the cross-country ability. A simplified calculation of indicators of cross-country ability of heavy trucks is presented.]]></description>
      <pubDate>Fri, 18 Mar 2022 12:17:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/1910282</guid>
    </item>
    <item>
      <title>Mechanical Performance of Biotreated Sandy Road Bases</title>
      <link>https://trid.trb.org/View/1891279</link>
      <description><![CDATA[This study investigated the performance of microbially induced calcite precipitation (MICP) in reinforcing road bases reconstituted with calcareous or silica sands. Four testing models were prepared by the surface percolation method at two cementation levels. A series of tests for California bearing ratio (CBR) and unconfined compressive strength (UCS) were performed to examine the strength of biotreated samples at the model and element scales. Scanning electron microscopy (SEM) tests were conducted on specimens sectioned from the four road base samples to investigate the microstructure of the biotreated sands. The test results showed that the strength of the biotreated road bases increased and then decreased with an increase in soil depth due to clogging in the upper layer. Calcareous sand samples demonstrated better biotreated performance than silica sand samples. The SEM results showed that the calcium carbonate (CaCO3) produced by MICP treatment can coat and bond grains and fill voids, which is more apparent in the upper portion of the bases. The morphologies of the CaCO3 precipitate in the calcareous and silica sand samples were different; this probably resulted from differences in the grain roughness and minerology of the two sands.]]></description>
      <pubDate>Tue, 30 Nov 2021 10:20:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/1891279</guid>
    </item>
    <item>
      <title>Dust Palliative Mean Particle Residence Time Calculator</title>
      <link>https://trid.trb.org/View/1764431</link>
      <description><![CDATA[Previous research efforts at University of Alaska Fairbanks (UAF) have established that dust palliative performance may be compared using a calculation called the mean particle residence time (tau, or MPRT). The MPRT value is computed using linear regression techniques to determine the time when the dust palliative loses its effectiveness. A technician tests the palliative using a dustfall column and a nephelometer to measure the concentration of PM10 over time. The technician needs to manually process this raw data with an Excel spreadsheet making dust palliative MPRT reports time-consuming and prone to error. Finally, the certifying technician prints and files the report for future reference which limits future dissemination. The authors developed a web-based calculator, called UAFDUST, to automate the process of producing the MPRT report. UAFDUST combines a web app front end using Google's Angular library with a PHP and SQL database backend. This database enables a laboratory to record metadata about the dust palliative including the dustfall column testing date and technician, certification date, and certifying technician. The app calculates the MPRT and produces accompanying linear regression plots. The UAFDUST app stores dust palliative MPRT tests in a public database and trained laboratory technicians may contribute new data.]]></description>
      <pubDate>Mon, 01 Feb 2021 16:08:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/1764431</guid>
    </item>
    <item>
      <title>Analytical hierarchy process as dust palliative selection tool</title>
      <link>https://trid.trb.org/View/1708289</link>
      <description><![CDATA[Analytical hierarchy process (AHP) is a multicriteria decision-making tool with diverse applications. Previous studies indicated AHP can be used as a tool for infrastructure management including pavement management and pavement type selection. In this paper, the use of AHP as a dust palliative selection tool is introduced. Fugitive dust in unpaved roads is commonly controlled using various dust palliatives. There are different types of commercial dust palliatives available in the market. Selection of appropriate dust palliative that serves its function without compromising budget and environment is not an easy task. So far, several guidelines have been published for selecting appropriate dust palliative based on surface material type, traffic volume, climate condition and road geometry. However, based on these guidelines, it is likely to have more than one viable dust palliative. These competing candidate dust palliatives should be compared among each other based on additional criteria to select the most appropriate of all. This can be done using the analytical hierarchy process. The use of AHP as a dust palliative selection tool is demonstrated in the paper using case study data and data from the literature.]]></description>
      <pubDate>Mon, 08 Jun 2020 15:34:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/1708289</guid>
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