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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>Weight and Speed Optimization for Goods Trains on Cargo-Intensive Railway Sections</title>
      <link>https://trid.trb.org/View/2407944</link>
      <description><![CDATA[This article focuses on the issue of optimising the transport process of cargo-intensive sections analyses the section capacity and outlines the most relevant ways of increasing carrying capacity and throughput today. In order to reduce capital expenditures for capacity enhancement the optimization task on revealing and determining the factors’ values influencing the carrying capacity was formed. Rational location of locomotive fleet on the sections allows to increase weight standards of goods trains on the one hand and on the other hand with useful track length less than 1050 m a reserve of locomotive capacity appears. On sections with low gradient up to 𝑖ₚ < 8‰ the reserve should be used to increase running speed while on sections with difficult profile 𝑖ₚ > 20‰ the reserve should be used to increase weight standards of the train. The proposed methodology made it possible to determine the optimum values of weight norms and speeds on the basis of the obtained values of running speed parameters and the division of the train traffic into three categories (light, mixed and heavy) using the optimum type of locomotive 2TE116. The results obtained prove the relevance of the study and show that the main factor that has a significant impact on carrying capacity is the locomotive performance. When determining carrying capacity the average train weight should be used rather than the weight standard set by the train schedule.]]></description>
      <pubDate>Thu, 21 Aug 2025 09:19:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2407944</guid>
    </item>
    <item>
      <title>An Urban Modeling Analysis of the Transport Network in the City of Bogor to Observe the Best Choice of a Transport Model</title>
      <link>https://trid.trb.org/View/2551251</link>
      <description><![CDATA[Transportation is an important part of people's lives, including access to connect one route to another. This study aims to obtain the existing conditions and level of service of public transportation on the Salabenda-Pasar Anyar route. The research method uses a quantitative method. The indicators used in the evaluation refer to applicable regulations. The performance of existing public transportation, namely: load factor does not meet the standard provisions of less than 70%, speed also does not meet the standard provisions of 25 km/hour, travel time results meet the standard provisions of 1-1.5 minutes, waiting time results meet the standard provisions of 5-10 minutes but on Saturdays it does not meet the standard provisions of 5-10 minutes, and headway results have met the standard 1-12minutes. The level of public transportation service on the research route with the characteristics of respondents based on female gender is 56.5%, age 20-30 years is 54.50%, last education is senior high school is 49.75%, and based on occupation, namely students/college students are 32%, more use public transportation route Salabenda-Pasar Anyar.]]></description>
      <pubDate>Fri, 20 Jun 2025 11:58:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2551251</guid>
    </item>
    <item>
      <title>Express Freight Transportation of Railway in China</title>
      <link>https://trid.trb.org/View/2264045</link>
      <description><![CDATA[The article analyses the circumstance of China's railway transportation and points out that the low freight train running speed and the unknowable transit period are the two main problems of their railway transportation. Then the article provides the way to solve the problems. It is to establish the express goods service system in China. Thus it can improve the freight train running speed and change the unknowable transit period to the knowable one.]]></description>
      <pubDate>Mon, 13 Jan 2025 12:02:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2264045</guid>
    </item>
    <item>
      <title>The mechanism of polygonal wheel wear considering a three-dimensional profile</title>
      <link>https://trid.trb.org/View/2444931</link>
      <description><![CDATA[Wheel polygonal wear is one of the most serious problems in the railway industry nowadays. To study the mechanism of wheel polygonal wear, the wear prediction model was established. The three-dimensional wheel profile model and the improved USFD wear prediction algorithm were used to research the wear state of the wheel. The vehicle system dynamic characteristics and wheel wear state under different running speeds are studied. The results show that the vibration state of the wheel will be affected by the vertical and lateral coupling vibration of the wheel when considering the three-dimensional wheel polygonal wear. Due to the influence of coupled vibration, the wheel will appear larger wheel-rail force fluctuation points at different phase angles. The large wheel-rail force fluctuation at these different phase angles is one of the reasons for the formation of wheel polygonal wear. At the same time, the natural mode of the vehicle system will also affect the order of the wheel polygon and the amplitude of the wheel polygon. This study provides a new idea for the research of the wheel polygon mechanism.]]></description>
      <pubDate>Wed, 13 Nov 2024 13:16:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/2444931</guid>
    </item>
    <item>
      <title>Analysis and Forecast of Railway Freight Ton-Kilometers Based on Partial Least Square Regression</title>
      <link>https://trid.trb.org/View/2283009</link>
      <description><![CDATA[Railway Freight Ton-Kilometers (RFTK) mainly results from the interaction between the railway freight transportation demands (RFTD) and the effective supplies of the railway transportation capacity. Based on the qualitative analysis of the influence factors of RFTK, some variables are selected as the influence factors reflecting the supplies of railway transportation capacity. They are the length of railways in operation, the length of electrified railway, the double-tracking length weight, the automatic blocking length weight and the running speed of freight, trains; other variables are selected as the influence factors reflecting the situation of the national economy. They are GDP, the industry production value, the coal output, the total value of imports and exports. The model is built by the means of Partial Least Square Regression (PLS). Modeling is realized by the software SAS 9.0. The results indicate that: (1) the model built by PLS is effective and feasible in this problem (2) In recent years, although the extension scale in the railroad network of the country is not small, it can not match the rapid economic growth; In addition, the running speed of freight trains has been slow for a long time. These are all the restrictive factors of the increase of RFTK. The enhancement of the railway transportation capacity in the country has to depend mainly on the increase of the level of railway technical equipment modernization.]]></description>
      <pubDate>Thu, 26 Sep 2024 15:25:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/2283009</guid>
    </item>
    <item>
      <title>Speed Regulation of Passenger Car Based on Side Wind Speed and Direction</title>
      <link>https://trid.trb.org/View/2282638</link>
      <description><![CDATA[Numerical simulation has been made to predict the aerodynamic loads on a passenger car model. The relation between aerodynamic coefficients and yaw angles is calculated. At the same time a math model of train's overturning is built based on moment balance, and the relationship among the highest safe running speed of train and wind speed and direction is studied. At last train speed regulation is put forward based on the side wind speed and wind direction. The results show that speed regulation based on wind speed and direction will greatly improve the transportation capability of the railway line.]]></description>
      <pubDate>Thu, 29 Aug 2024 09:44:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/2282638</guid>
    </item>
    <item>
      <title>Effects of train speed on dynamic performance of shoe-rail interaction system</title>
      <link>https://trid.trb.org/View/2373950</link>
      <description><![CDATA[The increase of the running speed of electric train has a certain influence on the dynamic performance of coupling of conductor rail and collector shoe. In this paper, the mechanical characteristics of coupling vibration between shoe and rail for high-speed trains are studied by using a numerical simulation method, and the effects of train speed on the vibration law of shoe-rail interaction system are analyzed. The results show that both the maximum displacement of the rail and the maximum contact force between the shoe and the rail increase with the increase of the train speed. The bending moment of the rail, the maximum displacement of the shoe, the elastic and viscous forces of the shoe all decrease first and then increase. In particular, when the train speed increases from 275 to 300 km/h, the displacement, bending moment, contact force, and other mechanical quantities increase significantly, which indicate that it will lead to a sharp increase in vibration degree when the train speed exceeds 275 km/h. Therefore, in the case of actual operating parameters in this paper, it is recommended that the train speed does not exceed 275 km/h.]]></description>
      <pubDate>Thu, 09 May 2024 16:15:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/2373950</guid>
    </item>
    <item>
      <title>A New Multi-objective Solution Approach Using ModeFRONTIER and OpenTrack for Energy-Efficient Train Timetabling Problem</title>
      <link>https://trid.trb.org/View/1975544</link>
      <description><![CDATA[Trains move along the railway infrastructure according to specific timetables. The timetables are based on the running time calculation and they are usually calculated without considering explicitly energy consumption. Since green transportation is becoming more and more important from environmental perspectives, energy consumption minimization could be considered also in timetable calculation. In particular, the Energy-Efficient Train Timetabling Problem (EETTP) consists in the energy-efficient timetable calculation considering the trade-off between energy efficiency and running times. In this work, a solution approach to solve a multi-objective EETTP is described in which the two objectives are the minimization of both energy consumption and the total travel time. The approach finds the schedules to guarantee that the train speed profiles minimize the objectives. It is based on modeFRONTIER and OpenTrack that are integrated by using the OpenTrack Application Programming Interface in a modeFRONTIER workflow. In particular, the optimization is made by modeFRONTIER, while the calculation of the train speed profiles, energy consumption and total travel time is made by OpenTrack. The approach is used with Multi-objective Genetic Algorithm-II and the Non-dominating Sorting Genetic-II, which are two genetic algorithms available in modeFRONTIER. The solution approach is tested on a case study that represents a real situation of metro line in Turkey. For both algorithms, a Pareto Front of solution which are a good trade-off between the objectives are reported. The results show significant reduction of both energy consumption and total travel time with respect to the existing timetable.]]></description>
      <pubDate>Mon, 11 Sep 2023 11:39:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/1975544</guid>
    </item>
    <item>
      <title>Influence of shortwave irregularity on increasing the vehicle running speed on bi-block ballastless track lines</title>
      <link>https://trid.trb.org/View/2212554</link>
      <description><![CDATA[Compared with slab ballastless track, bi-block ballastless track has the advantages of simpler constructed components and better economy, and has been used in high-speed railways for nearly 20,000 km in China. During the construction, the position deviation between sleepers and the disturbance of sleeper position caused by track bed concrete pouring can easily lead to shortwave irregularity with wavelength of 1 ∼ 2 m of bi-block ballastless track. Massive detection data on several high-speed railway lines showed that the standard deviation of vertical wheel-rail contact forces on bi-block ballastless track was about 58% higher than that on slab ballastless track. In this paper, a vehicle-track coupled dynamic analysis model was established, which can consider 1 ∼ 2 m shortwave irregularities of the track. Under the current construction and operation control standards, the dynamic responses of vehicles and tracks under different running speeds were studied. The results showed that vertical shortwave irregularity mainly affected the dynamic response of the wheel and rail, and rarely affected the dynamic response in other components. Compared with no shortwave irregularity, when the track had shortwave irregularity with σv = 0.8 mm, the peak value of the vertical acceleration of wheelset increased by 4.1 times, the standard deviation of wheel-rail contact force increased by 3.9 times, the vertical acceleration of frame increased by 1.7 times, and the vertical acceleration of track bed increased by 1.8 times, while the vibration acceleration of car body had almost no effect. When the track had shortwave irregularity with σh = 0.8 mm, the lateral acceleration of wheelset increased by 2.3 times. When the track had shortwave irregularity with σv = 0.8 mm and the vehicle speed increased to 450 km·h−1, the wheel load reduction rate reached 0.85, which exceeded the safety limit. Consider the results of this study, following suggestions can be obtained:(1) the shortwave irregularity with wavelength of 1 ∼ 2 m can be measured indirectly by the standard deviation of wheel-rail vertical contact force or wheelset vibration acceleration. (2) To control the wheel load reduction rate within 0.6, the standard deviation of random vertical irregularity should be controlled within 0.6 mm when running speed is 350 km/h, and within 0.4 mm when running speed is 400 km/h or above.]]></description>
      <pubDate>Mon, 28 Aug 2023 09:34:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/2212554</guid>
    </item>
    <item>
      <title>Impact of Road Pavement Condition on Vehicular Free Flow Speed, Vibration and In-Vehicle Noise</title>
      <link>https://trid.trb.org/View/2166498</link>
      <description><![CDATA[Road  infrastructure  in good  condition  is  a  key  requirement  for efficient  transportation  systems  which  leads  to economic prosperity and improved quality of life. However, road surface conditions deteriorate over time according to traffic loads and environmental factors. Poor road conditions lead to congestion, accidents, lost productivity, and driver fatigue. This work considers the relationship between road pavement condition and vehicle speed, vibration, and in-vehicle noise. A 7 km section of the Grand Trunk Road, Peshawar, Pakistan divided into 280 segments (140 for each lane), of length 50 m was observed and the Pavement Condition Index (PCI) of each segment was determined based on the  recurrent  distress  type  and  density  according  to  ASTM  D6433-011  guidelines.  The  number  of  very  good, satisfactory, fair, poor, and very poor conditions are 51, 52, 81, 48, and 42, respectively. The mobile app BotlnckDectr was  employed  to  measure  vehicle  speed,  RPM,  noise,  vibration,  GPS  location,  and  time.  Statistical  analysis  was employed to determine the relationship between PCI and vehicle speed, vibration, and in-vehicle noise. The results obtained indicate that noise and vibration increase by 3.3% and more than 30%, respectively, as the pavement condition changes from good to very poor, and vehicle speed decreases by 8.8%.]]></description>
      <pubDate>Wed, 28 Jun 2023 16:29:15 GMT</pubDate>
      <guid>https://trid.trb.org/View/2166498</guid>
    </item>
    <item>
      <title>Speed Planning Method for Autonomous Driving Considering Front / Rear Tire Force and Yaw Moment</title>
      <link>https://trid.trb.org/View/2145995</link>
      <description><![CDATA[In turning at high speed, a vehicle tends to deviate from a target path because the moment to car rotating becomes large. Taking lateral acceleration and transient moment into calculation is valuable to plan vehicle running speed within longitudinal, lateral, and angular acceleration, which can be generated by front and rear tires. Through analysis and verification with the test vehicle, it's shown that the proposed speed planning method that reflects generating rotating moment improves traceability onto trajectory.]]></description>
      <pubDate>Thu, 25 May 2023 13:51:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/2145995</guid>
    </item>
    <item>
      <title>Aerodynamic loads and bridge responses under train passage: Case study of an overpass steel box-girder cable-stayed bridge</title>
      <link>https://trid.trb.org/View/1905258</link>
      <description><![CDATA[Increased train speeds have led to significant train-induced wind problems. This paper describes a numerical study of the aerodynamic loads produced when a train passes under a bridge and the bridge dynamic response based on a steel box-girder cable-stayed bridge. The results indicate that the wind pressure on the bottom plate and the maximum lift on the beam sections increase as the train speed increases or as the clearance under the bridge decreases. Changes in the intersection angle are found to have a greater impact on the 1/4-span and 3/4-span regions. The effects of the various influencing factors are basically the same in the construction and operation stages. As the train speed increases or the clearance under the bridge decreases, the bridge responses exhibit an upward trend. As the intersection angle decreases, the vibration displacement tends to increase, but the effects on the vibration acceleration and maximum counter-force of the temporary pier are not consistent. Compared with the construction stage, the dynamic responses of the main girder are smaller in the operation stage due to the larger overall rigidity and the support constraints. In the parameter ranges investigated in this study, the absolute values of maximum vertical bridge vibration displacement and acceleration decrease from 4 to 16 mm and from 85 to 400 mm/s2, respectively, in the construction stage to 1–5 mm and 42–174 mm/s2 in the operation stage. Moreover, the counter-force falling on the temporary pier after the main girder turns does not exceed the 2000-kN positive force or 300-kN negative force limits. In the operation stage, the bridge vibration responses will not affect the comfort of pedestrians.]]></description>
      <pubDate>Mon, 11 Apr 2022 10:44:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1905258</guid>
    </item>
    <item>
      <title>Study on Traffic Detector Data Cleaning and Characteristic Analysis</title>
      <link>https://trid.trb.org/View/1897511</link>
      <description><![CDATA[With the development of collecting methods and information technology, more traffic detector data can be used to study traffic phenomena. However, the direct use of original data with quality problems to the transportation applications would result in unstable and unsafe application results. Therefore, it is necessary to develop an effective model for road traffic flow data cleaning and repair, so as to obtain the correct traffic information and grasp the law of traffic demand. This study, concentrating in Shanghai urban road intersections, uses SCATS and FCD data as sources and establishes a cleaning and repair model to preprocess data from detectors. The precision of the model is validated by corresponding data. By displaying the characteristics of the running speed and flow in urban roads, the authors find that the error of the model can be controlled at a reasonable level.]]></description>
      <pubDate>Mon, 07 Feb 2022 09:43:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/1897511</guid>
    </item>
    <item>
      <title>Numerical Investigation on Aerodynamic Characteristics of High-Speed-Train on Half-Embankment and Half-Cutting Transition Section under Crosswind</title>
      <link>https://trid.trb.org/View/1756669</link>
      <description><![CDATA[To examine the aerodynamic characteristics (AC) of high-speed-train (HST) running on half-embankment and half-cutting transition section (HEHCTS) under crosswind, a CRH3 HST is taken as the object. The AC of the HST running at four speeds and under crosswind action with five speeds are numerically investigated, and the correlation changing rules between the HST AC and the HST speed or crosswind speed were obtained. When the HST runs on HEHCTS at different speeds and under different-speed crosswind, the lateral forces (LFs), and overturning moments (OMs) acted on the head carriage are the largest. With the increase of crosswind speed or HST speed, the increases of the LFs and OMs on the head carriage are the largest. When the HST speed is 350 km/h or the crosswind speed is 30 m/s, the AC parameters of carriages have cubic relationships with the crosswind speed or HST speed. Crosswind speed has greater influence on HST’s AC than HST speed.]]></description>
      <pubDate>Thu, 25 Mar 2021 09:35:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/1756669</guid>
    </item>
    <item>
      <title>A computational simulation study on the dynamic response of high-speed wheel–rail system in rolling contact</title>
      <link>https://trid.trb.org/View/1711857</link>
      <description><![CDATA[The dynamic wheel–rail responses during the rolling contact process for high-speed trains were investigated using the explicit finite element code LS-DYNA 971. The influence of train speed on the wheel–rail contact forces (including the vertical, longitudinal, and lateral forces), von Mises equivalent stress, equivalent plastic strain, vertical acceleration of the axle, and the lateral displacement of the initial contact point on the tread, were examined and discussed. Simulation results show that the lateral and longitudinal wheel–rail contact forces are very smaller than the corresponding vertical contact forces, and they seem to be insensitive to train speed. The peak value of dynamic vertical wheel–rail contact force is approximately 2.66 times larger than the average quasi-static value. The elliptical wheel–rail contact patches have multiple stress extreme points due to the plastic deformation of the wheel tread and top surface of the rail. The vertical acceleration value of the axle in the steady condition is around ±5 m/s² for the perfected wheel–rail system with the running speed below 300 km/h.]]></description>
      <pubDate>Fri, 29 Jan 2021 16:26:56 GMT</pubDate>
      <guid>https://trid.trb.org/View/1711857</guid>
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