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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=PHNlYXJjaD48cGFyYW1zPjxwYXJhbSBuYW1lPSJkYXRlaW4iIHZhbHVlPSJhbGwiIC8+PHBhcmFtIG5hbWU9InN1YmplY3Rsb2dpYyIgdmFsdWU9Im9yIiAvPjxwYXJhbSBuYW1lPSJ0ZXJtc2xvZ2ljIiB2YWx1ZT0ib3IiIC8+PHBhcmFtIG5hbWU9ImxvY2F0aW9uIiB2YWx1ZT0iMCIgLz48L3BhcmFtcz48ZmlsdGVycz48ZmlsdGVyIGZpZWxkPSJpbmRleHRlcm1zIiB2YWx1ZT0iJnF1b3Q7UHJvYmFiaWxpc3RpYyBhbmFseXNpcyZxdW90OyIgb3JpZ2luYWxfdmFsdWU9IiZxdW90O1Byb2JhYmlsaXN0aWMgYW5hbHlzaXMmcXVvdDsiIC8+PC9maWx0ZXJzPjxyYW5nZXMgLz48c29ydHM+PHNvcnQgZmllbGQ9InB1Ymxpc2hlZCIgb3JkZXI9ImRlc2MiIC8+PC9zb3J0cz48cGVyc2lzdHM+PHBlcnNpc3QgbmFtZT0icmFuZ2V0eXBlIiB2YWx1ZT0icHVibGlzaGVkZGF0ZSIgLz48L3BlcnNpc3RzPjwvc2VhcmNoPg==" 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>
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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>Equitable location of facilities in a region with probabilistic barriers to travel</title>
      <link>https://trid.trb.org/View/1605666</link>
      <description><![CDATA[This paper studies a planar multi-facility location problem that considers the presence of a restricted region with probabilistic position. This problem seeks to locate facilities in an equitable manner by minimizing the maximum expected distance traveled from demand points to access a facility, as well as distances between locations of new facilities. The authors propose a heuristic to solve this problem that combines a bounding approach with a split-divide-and-conquer strategy. Computational study shows that this heuristic produces high-quality solutions in reasonable run-times. The authors report findings from a case-study involving locating police facilities in Kingston-Upon-Thames.]]></description>
      <pubDate>Mon, 29 Jul 2019 11:03:28 GMT</pubDate>
      <guid>https://trid.trb.org/View/1605666</guid>
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    <item>
      <title>Probabilistic versus Deterministic Assessment of the Minimum Structural Damping Required to Prevent Galloping of Dry Bridge Hangers</title>
      <link>https://trid.trb.org/View/1629713</link>
      <description><![CDATA[The risk of large-amplitude vibrations of bridge hangers due to galloping instabilities has posed a challenge to the engineering and research communities. Galloping vibrations can lead to serviceability problems and reduce fatigue life. A number of aeroelastic models have been developed to predict the unstable behavior and to design counteracting measures, i.e., shape modifications and structural damping addition. All the proposed procedures generally consider that the parameters are assigned according to deterministic values. A framework is proposed for the deterministic and probabilistic assessment of the minimum structural damping required to prevent galloping of bridge hangers based on the output of a two-degree-of-freedom sectional quasi-steady aeroelastic model. All the variables required to define the hanger dynamics, the sheath aerodynamics, and the local wind climate are considered. Because of the large uncertainties and of the nonlinear nature of the problem, the distribution of the minimum structural damping required to prevent galloping is obtained by Monte Carlo simulations. An application of the method to the proposed Messina Straits crossing bridge is presented. Starting from wind tunnel measurements of the aerodynamic coefficients of a real plain high-density polyethylene (HDPE) cable sheath, the random nature of the aerodynamics is shown, which is ascribed to the cable irregularities (surface roughness, section distortion, and axis curvature). Then the statistical variation of the parameters of the model is considered, based on real data derived from wind tunnel tests and from the wind climate measured at the site. The distributions of the parameters defining the hanger dynamics are assigned according to typical values. Using a normal and a log-normal model of capacity, the probability of failure is calculated. The results are discussed and compared with conventional approaches based on the definition of the deterministic variables. Finally, using a deterministic model of capacity, a simplified closed-form equation for the evaluation of the structural damping needed to prevent galloping in a probabilistic-based performance approach is proposed.]]></description>
      <pubDate>Mon, 29 Jul 2019 11:03:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/1629713</guid>
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    <item>
      <title>Simplified Standard Penetration Test Performance-Based Assessment of Liquefaction and Effects</title>
      <link>https://trid.trb.org/View/1597508</link>
      <description><![CDATA[The purpose of the research presented is to provide the benefit of the full performance-based probabilistic earthquake hazard analysis, without requiring special software, training, and experience, while using Standard Penetration Test (SPT) data from site soil borings. To do this, simplified models of liquefaction triggering, lateral spread displacements, post-liquefaction settlements, and seismic slope displacements that approximate the results of the full probabilistic analysis were developed. These simplified methods are designed to require only a few calculations programmed into a spreadsheet and a provided liquefaction parameter map. The simplified procedures are based on the Boulanger and Idriss (2012) probabilistic liquefaction triggering; Youd et al. (2002) for lateral spread; Cetin et al. (2009) and (Ishihara and Yoshimine (1992) for post-liquefaction settlements; and lastly, Rathje & Saygili (2009), and Bray & Travasarou (2007) for seismic slope displacement empirical models. The new simplified procedures are based on retrieving a reference parameter value (i.e. CSRref (%), log D sub Href, etc.) from a hazard-targeted liquefaction parameter map, and calculating site-specific correction factors to adjust the reference value to represent the site-specific conditions. The simplified procedures were validated by comparing the results of the simplified analysis with a full performance-based analysis for 10 cities of varying seismicity. The results show that the simplified procedure is within 5% error of the full performance-based procedure. These maps were created for Alaska (only liquefaction triggering and lateral spread), Connecticut, Idaho, Montana, South Carolina, Oregon, and Utah at the 475, 1033, and 2475 year return periods. The simplified procedures were compared with the deterministic and pseudo-probabilistic procedures. The deterministic procedure significantly overpredicts hazard in regions of low seismicity, slightly overpredicts hazard in regions of medium seismicity, and slightly underpredicts hazard in areas of high seismicity when compared to the simplified procedure at the 475 and 2475 year return periods. The pseudo-probabilistic procedure returns results very similar to the simplified method at the 1033 year return period.]]></description>
      <pubDate>Mon, 22 Apr 2019 21:27:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/1597508</guid>
    </item>
    <item>
      <title>Probabilistic-Based Assessment of Existing Steel-Concrete Composite Bridges – Application to Sousa River Bridge</title>
      <link>https://trid.trb.org/View/1574278</link>
      <description><![CDATA[This paper presents a framework to assess the safety of existing structures, combining deterministic model identification and reliability assessment techniques, considering both load-test and complementary laboratory test results. Firstly, the proposed framework, as well as the most significant uncertainty sources are presented. Then, the developed model identification procedure is described. Reliability methods are then used to compute structural safety, considering the updated model from model identification. Data acquisition, such as that collected by monitoring, non-destructive or material characterization tests, is a standard procedure during safety assessment analysis. Hence, Bayesian inference is introduced into the developed framework, in order to update and reduce the statistical uncertainty. Lastly, the application of this framework to a case study is presented. The example analyzed is a steel and concrete composite bridge. The load test, the developed numerical model and the obtained results are discussed in detail. The use of model identification allows the development of more reliable structural models, while Bayesian updating leads to a significant reduction in uncertainty. The combination of both methods allows for a more accurate assessment of structural safety.]]></description>
      <pubDate>Thu, 21 Feb 2019 09:54:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/1574278</guid>
    </item>
    <item>
      <title>Fatigue Resistance and Reliability of High Mast Illumination Poles (HMIPs) with Pre-Existing Cracks: Final Report</title>
      <link>https://trid.trb.org/View/1573428</link>
      <description><![CDATA[High mast illumination poles (HMIPs) are used throughout Texas and the U.S. to provide lighting along highways and at interchanges. Texas currently has about 5000 HMIPs, varying in height from 100 to 175 ft. Failures of HMIPs have been reported in several states, attributed to failures at the shaft-to-base plate connection. No collapses of HMIPs have been reported in Texas. However, recent studies have shown that many galvanized HMIPs in Texas have pre-existing cracks at their shaft-to-base plate connection, most likely caused by the galvanization process before the poles were placed in service. Previous research has also shown that pre-existing cracks may significantly reduce the fatigue life of galvanized HMIPs. The Texas Department of Transportation (TxDOT) has identified three major issues/concerns with respect to HMIPs with pre-existing cracks: the lack of reliable experimental data about the fatigue life of pre-cracked HMIP base-connection details; the significant uncertainty regarding the natural wind response of HMIPs to the various major wind environments in Texas (much of this uncertainty is related to the lack of measured data from comprehensive field studies); and, due to this lack of data, the ‘safe/serviceable’ life of in-service TxDOT HMIPs with pre-existing cracks cannot be reliably predicted. The main goal of this research project was to generate data and information to support a probabilistic-based assessment of the remaining life of HMIPs with pre-existing cracks. The research included extensive laboratory fatigue testing of HMIPs with pre-existing cracks, field monitoring of in-service HMIPs at five locations across Texas, and the development of a reliability based framework to assess the safety of in-service HMIPs with pre-existing cracks. The results of this study show a wide range in the predicted lives of HMIPs with pre-existing cracks at different locations throughout the state. Based on a probability of failure of 5 percent, the predicted fatigue life at a number of locations analyzed throughout the state showed predicted lives varying from approximately 30 years to over 300 years. The variation in predicted lives is mainly affected by differing wind characteristics at each location.]]></description>
      <pubDate>Mon, 17 Dec 2018 12:19:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/1573428</guid>
    </item>
    <item>
      <title>Probability Analysis of Flexural Fatigue Data of High Volume Fly Ash Concrete</title>
      <link>https://trid.trb.org/View/1558684</link>
      <description><![CDATA[There is a need for the development of Eco friendly and cost effective material for the rigid pavement construction. High volume fly ash concrete suits the pavement concrete due to its many advantages. The knowledge of fatigue behavior is essential for the design of concrete pavements. This paper describes the probabilistic analysis of flexural fatigue behavior of high volume fly ash concrete. High volume fly ash concrete mixtures, satisfying the criteria of pavement concrete, were proportioned using low calcium fly ash. A total number of 225 beam specimens at three cement replacement levels (0, 50, and 60%) were tested under non reversed cyclic wave loading. Log normal model was found to be satisfactory for the fatigue life distribution in all the cases. The parameters of the log normal distribution model were found to be dependent on the stress level. Fatigue model was developed in the form of relation between the stress level (S) and the fatigue life (N). S-N relations were established for high volume fly ash and reference concrete mixes at different reliability levels.]]></description>
      <pubDate>Sun, 16 Dec 2018 21:39:09 GMT</pubDate>
      <guid>https://trid.trb.org/View/1558684</guid>
    </item>
    <item>
      <title>Pavement Surface Condition Prediction by Markov Chains</title>
      <link>https://trid.trb.org/View/1567410</link>
      <description><![CDATA[A model for prediction of pavement surface condition plays a vital role in Pavement Management System (PMS). In developing countries like India, PMS is the needed approach for the optimum utilisation of the available scarce resources. Pavement management System is concerned with optimal use of materials in time and space, leading to cost optimization. This Paper focuses on methodology involved in the prediction of pavement condition using probabilistic techniques. As pavement condition prediction parameter like traffic loading, pavement materials, construction methods and environmental condition are not deterministic therefore probabilistic techniques is used i.e. the present study. Markov chains have the property that probabilities involving the process will evolve in the future depend only on the present state of the process and so are independent of the events in the past. The state of the transition matrix will be defined based on the Pavement Condition Index (PCI) and element of the transition matrix will be determined by the probability method. Fifteen cycles was carried out because the expected design life of the bituminous roads is fifteen years. The probabilistic model requires only a minimal amount of data such as pavement class, pavement condition of two consecutive years and the pavement length. PCI shall be utilized as index and the present technique in pavement management systems will create good systems which may lead to more savings of the roads maintenance funds and enhance the ability of the roads network to provide better level of service.]]></description>
      <pubDate>Tue, 20 Nov 2018 10:11:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/1567410</guid>
    </item>
    <item>
      <title>Probabilistic Ex-Ante Appraisal of Major Transportation Projects</title>
      <link>https://trid.trb.org/View/1512828</link>
      <description><![CDATA[The authors advocate for Probabilistic Ex-ante Appraisal (PEAA) that goes beyond simple assessing a project's risks, by adding to the appraisal process the "Risk Treatment Planning" that traditionally is an element of the project risk management cycle. An analogy is made to the recent findings on how a human’s mind works: System 1 (effortless, automatic) and System 2 (strenuous, second view). It presents the main activities of the “risk treatment planning” when it acts as an extension of the PEAA. Furthermore the paper discusses the definition of “risk severity” applied to the PEAA results. It shows how the definition of risk’s severity changes when it is applied to the “threats” or when it is applied to the “opportunities” in respect of the risks that provide data to the PEAA. Next, it presents the case study of the largest single bore tunnel in the world that demonstrates the benefit of adopting an enhanced PEAA in the process of project management. The authors conclude that adopting risk treatment planning into the PEAA may improve the project’s performance by reducing the project uncertainties.]]></description>
      <pubDate>Tue, 29 May 2018 16:02:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/1512828</guid>
    </item>
    <item>
      <title>Estimation and application of a multi-class multi-criteria mixed paired combinatorial logit model for transport networks analysis</title>
      <link>https://trid.trb.org/View/1509269</link>
      <description><![CDATA[Probabilistic approach of transport network modelling has received significant attention in recent years. Despite the recent progress in this area, the full advantage of the potential capability of random utility choice models has not yet been fully realised. This research is intended to introduce a new approach of combining the state-of-the-art paired combinatorial logit route choice modelling and random coefficient choice models in traffic assignment. While the former addresses the problem of correlation among path utilities, the latter can capture the random taste heterogeneity in route choice decision-making. Including an additional monetary cost explanatory variable, the model would be able to assess a broader range of planning policies such as road pricing. In addition, distinguishing multiple classes of decision-makers, the model has allowed the introduction of demographic aspects of travellers into a network analysis process. Results showed a considerable difference between the flow patterns predicted by the proposed model and the traditional models.]]></description>
      <pubDate>Thu, 17 May 2018 14:46:09 GMT</pubDate>
      <guid>https://trid.trb.org/View/1509269</guid>
    </item>
    <item>
      <title>On the Presentation of Ship's Hull Girder Section Modulus in Probabilistic Formats</title>
      <link>https://trid.trb.org/View/1499015</link>
      <description><![CDATA[A probabilistic analysis for wave-induced hull girder bending stresses is normally evaluated using the so-called ‘annual’ probability density function (PDF) of hull girder section modulus. However, the design wave-induced loads given by Class Rules are specified for the whole design life of a ship. To solve this problem, a kind of PDF of hull girder section modulus considering ‘time period’ was introduced. A parametric study was performed to investigate the effects of the two types of PDFs of hull girder section modulus, namely the ‘annual’ and ‘time period’ PDFs, on the PDF of wave-induced hull girder bending stresses. The results show that the probability of exceeding given permissible hull girder bending stresses calculated using the ‘time period’ PDF of hull girder section modulus is smaller than that calculated based on the ‘annual’ PDF. A palpable difference between the two PDFs of wave-induced hull girder bending stresses occurs after 15 years.]]></description>
      <pubDate>Fri, 30 Mar 2018 09:54:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/1499015</guid>
    </item>
    <item>
      <title>Effect of fibre reinforcement on CBR behaviour of lime-blended expansive soils: reliability approach</title>
      <link>https://trid.trb.org/View/1502758</link>
      <description><![CDATA[The use of synthetic fibres as reinforcement to stabilise expansive soils is gaining momentum. As a contribution towards this growing field of research two different types of synthetic fibres, Fiber Mesh® and Fiber Cast®, were evaluated as a stabilisation alternative for expansive soils in the presence of lime. California bearing ratio (CBR) is chosen as a performance indicator as it is a good pointer towards pavement effectiveness. Variables such as length and amount of the fibres as well as curing period were studied. Both deterministic and probabilistic (or reliability) analyses is presented in this paper. While the deterministic analysis helps in understanding the measured experimental data, the probabilistic approach accounts for the stochastic nature of the experimental data and provides a better rationale for the design methods. The deterministic approach showed that the improvement in CBR increased with higher fibre contents and longer lengths and the effect was prominent when lime was used as a stabiliser. There were some exceptions to this behaviour, which were noted in the paper. The probabilistic analysis showed that the amount and lengths of fibres were important factors in CBR strength. It was also determined that the variation in the target CBR value had a considerable effect on optimising the length and amount of the fibres.]]></description>
      <pubDate>Fri, 16 Mar 2018 09:51:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/1502758</guid>
    </item>
    <item>
      <title>Probabilistic Evaluation of Pavement-Induced Excess Fuel Consumption Given Data Unavailability and Future Uncertainty</title>
      <link>https://trid.trb.org/View/1497114</link>
      <description><![CDATA[Pavement surface condition and structural properties affect vehicle fuel consumption and result in major contributions to the use phase impact of high-volume roads. This excess fuel consumption (EFC) is described through Pavement-Vehicle Interaction (PVI) as the effect of pavement texture, roughness, and deflection on the rolling resistance of a moving vehicle. The use of PVI models in pavement design and management decisions are hindered by data unavailability and uncertainties associated with the pavement life time, typically decades long. This study addresses data limitations through a probabilistic approach to evaluating PVI impacts in presence of lifecycle uncertainties. The probabilistic deflection and roughness induced EFCs are evaluated for nine data-availability scenarios. Surrogate data are used in absence of structural and material inputs along with distributions of vehicle load, speed, temperature, and roughness over the analysis period. Finally, the probabilistic EFC is evaluated for equivalent asphalt and concrete pavement designs and the data-availability scenarios. The probabilistic EFC results indicate that the proposed methodology for characterization and evaluation of uncertainty in PVI can statistically distinguish the EFCs in a comparative analysis.]]></description>
      <pubDate>Tue, 06 Mar 2018 16:22:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/1497114</guid>
    </item>
    <item>
      <title>Probabilistic Analysis of a Rock Tunnel Face Using Polynomial Chaos Expansion Method</title>
      <link>https://trid.trb.org/View/1498358</link>
      <description><![CDATA[The polynomial chaos expansion method was used to perform probabilistic analysis on a tunnel face driven in rock masses. The generalized Hoek-Brown (HB) failure criterion was used to characterize the strength of rock masses. Deterministic calculations of required face pressures were based on the upper bound limit analysis theory. Four HB input parameters, the geological strength index (GSI), the uniaxial compressive strength σc of the intact rock, the constant mi, and the disturbance factor Di, were considered as random variables. The influence of HB input parameter uncertainties on probability density functions of the required face pressures, sensitivity analysis, and failure probabilities were discussed with respect to different coefficients of variance (COVs), distribution types, and correlation coefficients. A reliability-based design was performed to compute probabilistic face pressures under different COVs at a target safety level. The obtained results show uncertainties in the input random variables have an important influence on the required face pressures, and it is necessary to analyze the problem in the probabilistic framework.]]></description>
      <pubDate>Tue, 20 Feb 2018 09:35:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/1498358</guid>
    </item>
    <item>
      <title>Dynamic model for pedestrian crossing in congested traffic based on probabilistic navigation function</title>
      <link>https://trid.trb.org/View/1500882</link>
      <description><![CDATA[More than 1.2 million people die in road crashes each year, and more than 20 million are severely injured, making it the 9th leading cause of death in the world (2.2% of all deaths globally). Pedestrian deaths comprise more than 35% of road accident deaths, mostly as a result of pedestrian-vehicle crashes. This paper proposes a new model for formulating the dynamics of the interaction between drivers and pedestrians at congested conflict spots where drivers and/or pedestrians do not closely follow the traffic laws and regulations. In this type of spots, characterized by heavy traffic, pedestrians and vehicles interact in close proximity, often requiring sharp and aggressive maneuvers to avoid crashes. The model is based on the Probabilistic Navigation Function (PNF), originally developed for robotics motion planning, that constructs a trajectory according to the probabilistic collision risks. According to this model, pedestrians construct a virtual risk map that assigns the entire crossing area with probabilities for a collision with vehicles, and then select their actions based on their perceived probability for collision. Many accidents can be interpreted in terms of the proposed model, either as a result of incorrect perception of risks, or, despite proper estimation of risks, by a wrong choice of collision maneuvers. The development of the model follows a theoretical and experimental investigation of pedestrian/vehicle interactions at crosswalks. The model is implemented in an agent-based simulation system for pedestrian/driver interaction, and is validated using video clips taken at several congested road spots. It can be used for analyzing the effect of changes in location architecture and traffic regulations for each spot. The model can also serve as a standard tool in simulations for assessing accident risks in urban environments. Finally, it can be utilized in control systems of autonomous vehicles and in drivers’ on-board alert systems.]]></description>
      <pubDate>Tue, 20 Feb 2018 09:31:28 GMT</pubDate>
      <guid>https://trid.trb.org/View/1500882</guid>
    </item>
    <item>
      <title>A chance-constrained two-stage stochastic programming model for humanitarian relief network design</title>
      <link>https://trid.trb.org/View/1498159</link>
      <description><![CDATA[The authors consider a stochastic pre-disaster relief network design problem, which mainly determines the capacities and locations of the response facilities and their inventory levels of the relief supplies in the presence of uncertainty in post-disaster demands and transportation network conditions. In contrast to the traditional humanitarian logistics literature, the authors develop a chance-constrained two-stage mean-risk stochastic programming model. This risk-averse model features a mean-risk objective, where the conditional value-at-risk (CVaR) is specified as the risk measure, and enforces a joint probabilistic constraint on the feasibility of the second-stage problem concerned with distributing the relief supplies to the affected areas in case of a disaster. To solve this computationally challenging stochastic optimization model, the authors employ an exact Benders decomposition-based branch-and-cut algorithm. The authors develop three variants of the proposed algorithm by using alternative representations of CVaR. The authors illustrate the application of their model and solution methods on a case study concerning the threat of hurricanes in the Southeastern part of the United States. An extensive computational study provides practical insights about the proposed modeling approach and demonstrates the computational effectiveness of the solution framework.]]></description>
      <pubDate>Wed, 24 Jan 2018 09:09:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/1498159</guid>
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