Transportation Research Record: Journal of the Transportation Research Board最新文献_第9页

Novel Approach for Reducing Train Wheel and Brake Shoe Wear Using Speed Profile Optimization 利用速度曲线优化减少列车车轮和制动蹄磨损的新方法

Transportation Research Record: Journal of the Transportation Research Board Pub Date : 2024-02-14 DOI: 10.1177/03611981231225652

Hasan Adeli, Ahmad Mirabadi, Shahin Yousefi, Saeed Fazel

引用次数: 0

Novel Approach for Reducing Train Wheel and Brake Shoe Wear Using Speed Profile Optimization 利用速度曲线优化减少列车车轮和制动蹄磨损的新方法

Transportation Research Record: Journal of the Transportation Research Board Pub Date : 2024-02-14 DOI: 10.1177/03611981231225652

Hasan Adeli, Ahmad Mirabadi, Shahin Yousefi, Saeed Fazel

引用次数: 0

Case Study on Instrumenting and Monitoring Geosynthetic-Reinforced Pile-Supported Mechanically Stabilized Earth Wall Built over Soft Soil 软土上建造的土工合成材料加固桩支撑机械稳定土墙的仪器和监测案例研究

Transportation Research Record: Journal of the Transportation Research Board Pub Date : 2024-02-14 DOI: 10.1177/03611981231224738

MohammadAli Izadifar, Murad Y. Abu-Farsakh, Shengli Chen

{"title":"Case Study on Instrumenting and Monitoring Geosynthetic-Reinforced Pile-Supported Mechanically Stabilized Earth Wall Built over Soft Soil","authors":"MohammadAli Izadifar, Murad Y. Abu-Farsakh, Shengli Chen","doi":"10.1177/03611981231224738","DOIUrl":"https://doi.org/10.1177/03611981231224738","url":null,"abstract":"This paper presents a case study on instrumenting, monitoring, and finite element modeling (FEM) of geosynthetic-reinforced pile-supported (GRPS) mechanically stabilized earth (MSE) walls. The GRPS-MSE wall was monitored using various instruments such as piezometers, earth pressure cells, shape-acceleration arrays (SAAs), and strain gauges. The performance criteria included efficacy, stress concentration ratio (SCR), differential settlement, and reinforcement tension. Collected data, such as excess pore-water pressures, contact pressures on pile and soft soil, differential settlements, and lateral displacement of MSE wall, were analyzed thoroughly. A 3D FEM was also developed to simulate the GRPS MSE wall, and the results are in good agreement with field data. The results demonstrated significant load transfer from soil to piles as a result of soil arching, yielding 30–32 SCR. The field efficacy was measured at 37.69 %, while the FEM efficacy was estimated as 42.4. Strains in geogrids within the geosynthetic-reinforced load transfer platform (GLTP) system were under 1%, less than the 5% maximum recommended by FHWA. The maximum differential settlement measured between pile cap and soft soil from SAAs is 7.1 mm, while it is estimated to be 8.3 mm from FEM. The MSE wall exhibited low lateral displacement (<25 mm), indicating enhanced stability because of GLTP. The comparison between five analytical GLTP design methods showed that the CUR226 methods gave the closest results to field measurements and FEM results. This study offers crucial insights into leveraging GLTP and MSE walls in highway construction.","PeriodicalId":509035,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":"433 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139839524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Laboratory Characterization of Additive-Modified Asphalt Concrete Mixtures 添加剂改性沥青混凝土混合物的实验室表征

Transportation Research Record: Journal of the Transportation Research Board Pub Date : 2024-02-12 DOI: 10.1177/03611981231224742

Matthew Kmetz, David Timm, Carolina Rodezno, Nam Tran, Fan Yin

{"title":"Laboratory Characterization of Additive-Modified Asphalt Concrete Mixtures","authors":"Matthew Kmetz, David Timm, Carolina Rodezno, Nam Tran, Fan Yin","doi":"10.1177/03611981231224742","DOIUrl":"https://doi.org/10.1177/03611981231224742","url":null,"abstract":"There is a need for a more rapid system of evaluation and implementation for new and existing asphalt additives, especially because of the prohibitive cost of full-scale performance evaluations. To help to meet this need, the Additive Group (AG) experiment at the National Center for Asphalt Technology (NCAT) was developed and began in 2021. A comprehensive laboratory evaluation of six mixtures, each modified with a popular additive type selected by the AG state DOT sponsors, was conducted. Simultaneously, full-scale test sections were constructed at the NCAT test track to evaluate the field performance and structure behavior of each modified mixture. Trafficking of these test sections is currently underway, and estimated to be completed in 2024, at which point an investigation linking the laboratory and field results will be done. This paper presents the completed laboratory evaluation of each AG mixture via complex dynamic modulus (E*), direct tension cyclic fatigue, and bending beam fatigue testing. The wet-process rubber modified mixture was found to have reduced E* and initial flexural stiffness, but increased fatigue resistance, relative to the styrene-butadiene-styrene (SBS)-modified control mixture. The dry-process rubber-modified mixture displayed similar trends, though to a lesser degree. Conversely, the dry-process plastic-modified mixture was found to have increased E* and initial flexural stiffness, but reduced fatigue resistance, relative to the SBS-modified control mixture. The other AG mixtures—a dry-process fiber and a wet-process plastic-modified mixture—were found to display E*, initial flexural stiffness, and fatigue resistance similar to that of the SBS-modified control mixture.","PeriodicalId":509035,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":"97 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139784452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Development of a Predictive Model for the Indirect Tensile Strength Load–Displacement Curve for Asphalt Mixtures 开发沥青混合料间接拉伸强度荷载-位移曲线预测模型

Transportation Research Record: Journal of the Transportation Research Board Pub Date : 2024-02-12 DOI: 10.1177/03611981241229091

Mohammed Abu Saq, Emad Kassem

{"title":"Development of a Predictive Model for the Indirect Tensile Strength Load–Displacement Curve for Asphalt Mixtures","authors":"Mohammed Abu Saq, Emad Kassem","doi":"10.1177/03611981241229091","DOIUrl":"https://doi.org/10.1177/03611981241229091","url":null,"abstract":"The indirect tensile (IDT) strength test is one of the common laboratory tests conducted to characterize asphalt mixtures. The IDT load–displacement curve is used to calculate various indicators to evaluate the cracking performance of asphalt mixtures. This study evaluated the effect of the mix composition on the IDT load–displacement curve. Asphalt mixtures with different characteristics, including binder content, binder grade, and mix gradation, were prepared and tested. The study developed statistical regression models to predict the entire IDT load–displacement curve using parameters that describe the mix composition and properties, including the binder complex shear modulus and phase angle, aggregate gradation, and binder content. The results demonstrated that the predicted model parameters were found to correlate well with those calculated from the experimental IDT load–displacement curves. All predicted cracking performance indicators calculated from the predicted IDT load–displacement curve had a strong correlation with those calculated from the measured IDT load–displacement curve. The proposed model can be used as a tool to check the preliminary cracking performance of the asphalt mixtures during the mix design stage. In addition, the mix composition can be adjusted to improve the cracking performance of the designed mix (e.g., adjust binder grade, binder content, gradation, etc.).","PeriodicalId":509035,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":"180 14","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139843173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Laboratory Characterization of Additive-Modified Asphalt Concrete Mixtures 添加剂改性沥青混凝土混合物的实验室表征

Transportation Research Record: Journal of the Transportation Research Board Pub Date : 2024-02-12 DOI: 10.1177/03611981231224742

Matthew Kmetz, David Timm, Carolina Rodezno, Nam Tran, Fan Yin

{"title":"Laboratory Characterization of Additive-Modified Asphalt Concrete Mixtures","authors":"Matthew Kmetz, David Timm, Carolina Rodezno, Nam Tran, Fan Yin","doi":"10.1177/03611981231224742","DOIUrl":"https://doi.org/10.1177/03611981231224742","url":null,"abstract":"There is a need for a more rapid system of evaluation and implementation for new and existing asphalt additives, especially because of the prohibitive cost of full-scale performance evaluations. To help to meet this need, the Additive Group (AG) experiment at the National Center for Asphalt Technology (NCAT) was developed and began in 2021. A comprehensive laboratory evaluation of six mixtures, each modified with a popular additive type selected by the AG state DOT sponsors, was conducted. Simultaneously, full-scale test sections were constructed at the NCAT test track to evaluate the field performance and structure behavior of each modified mixture. Trafficking of these test sections is currently underway, and estimated to be completed in 2024, at which point an investigation linking the laboratory and field results will be done. This paper presents the completed laboratory evaluation of each AG mixture via complex dynamic modulus (E*), direct tension cyclic fatigue, and bending beam fatigue testing. The wet-process rubber modified mixture was found to have reduced E* and initial flexural stiffness, but increased fatigue resistance, relative to the styrene-butadiene-styrene (SBS)-modified control mixture. The dry-process rubber-modified mixture displayed similar trends, though to a lesser degree. Conversely, the dry-process plastic-modified mixture was found to have increased E* and initial flexural stiffness, but reduced fatigue resistance, relative to the SBS-modified control mixture. The other AG mixtures—a dry-process fiber and a wet-process plastic-modified mixture—were found to display E*, initial flexural stiffness, and fatigue resistance similar to that of the SBS-modified control mixture.","PeriodicalId":509035,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":"65 14","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139844344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Development of a Predictive Model for the Indirect Tensile Strength Load–Displacement Curve for Asphalt Mixtures 开发沥青混合料间接拉伸强度荷载-位移曲线预测模型

Transportation Research Record: Journal of the Transportation Research Board Pub Date : 2024-02-12 DOI: 10.1177/03611981241229091

Mohammed Abu Saq, Emad Kassem

{"title":"Development of a Predictive Model for the Indirect Tensile Strength Load–Displacement Curve for Asphalt Mixtures","authors":"Mohammed Abu Saq, Emad Kassem","doi":"10.1177/03611981241229091","DOIUrl":"https://doi.org/10.1177/03611981241229091","url":null,"abstract":"The indirect tensile (IDT) strength test is one of the common laboratory tests conducted to characterize asphalt mixtures. The IDT load–displacement curve is used to calculate various indicators to evaluate the cracking performance of asphalt mixtures. This study evaluated the effect of the mix composition on the IDT load–displacement curve. Asphalt mixtures with different characteristics, including binder content, binder grade, and mix gradation, were prepared and tested. The study developed statistical regression models to predict the entire IDT load–displacement curve using parameters that describe the mix composition and properties, including the binder complex shear modulus and phase angle, aggregate gradation, and binder content. The results demonstrated that the predicted model parameters were found to correlate well with those calculated from the experimental IDT load–displacement curves. All predicted cracking performance indicators calculated from the predicted IDT load–displacement curve had a strong correlation with those calculated from the measured IDT load–displacement curve. The proposed model can be used as a tool to check the preliminary cracking performance of the asphalt mixtures during the mix design stage. In addition, the mix composition can be adjusted to improve the cracking performance of the designed mix (e.g., adjust binder grade, binder content, gradation, etc.).","PeriodicalId":509035,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":"12 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139783185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact of Settlement Size and Regional Density on the Frequency of Different Holiday Types 居民点规模和地区密度对不同类型假期频率的影响

Transportation Research Record: Journal of the Transportation Research Board Pub Date : 2024-02-12 DOI: 10.1177/03611981231224747

Tanja Scheffler, Eva Heinen

{"title":"Impact of Settlement Size and Regional Density on the Frequency of Different Holiday Types","authors":"Tanja Scheffler, Eva Heinen","doi":"10.1177/03611981231224747","DOIUrl":"https://doi.org/10.1177/03611981231224747","url":null,"abstract":"Despite its contribution to climate change, holiday travel has received less attention in research than daily travel. Research has revealed that individuals residing in dense and large settlements tend to travel more frequently and over longer distances. Whether this is attributable to compensation for shortcomings of dense cities or a reflection of lifestyle is still inconclusive, yet important to uncover for formulating mitigation strategies for the environmental impact. To advance this discussion, we analyze the 2019 Norwegian holiday travel survey to determine to what extent settlement size and regional density in Norway are associated with different holiday types that reflect different lifestyles and motivations. Using negative binomial and logistic regression while controlling for socioeconomic factors, we find that (1) it is not settlement size that influences the number of holiday trips, but whether a settlement lies in a dense county; (2) making nature getaways in Scandinavia and intercontinental trips are both positively associated with county density; (3) making city trips does not show a consistent link with spatial characteristics; (4) Mediterranean seaside holidays are typical for all Norwegians, no matter the place of residence. Our results indicate compensatory motivation behind nature getaways. However, dense everyday surroundings are not detrimental to visiting other densely populated areas on city vacations. The increased likelihood of intercontinental trips among people in dense areas may be explained by lifestyle and cosmopolitan attitudes rather than being a result of compensation.","PeriodicalId":509035,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":"60 15","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139844435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact of Settlement Size and Regional Density on the Frequency of Different Holiday Types 居民点规模和地区密度对不同类型假期频率的影响

Transportation Research Record: Journal of the Transportation Research Board Pub Date : 2024-02-12 DOI: 10.1177/03611981231224747

Tanja Scheffler, Eva Heinen

{"title":"Impact of Settlement Size and Regional Density on the Frequency of Different Holiday Types","authors":"Tanja Scheffler, Eva Heinen","doi":"10.1177/03611981231224747","DOIUrl":"https://doi.org/10.1177/03611981231224747","url":null,"abstract":"Despite its contribution to climate change, holiday travel has received less attention in research than daily travel. Research has revealed that individuals residing in dense and large settlements tend to travel more frequently and over longer distances. Whether this is attributable to compensation for shortcomings of dense cities or a reflection of lifestyle is still inconclusive, yet important to uncover for formulating mitigation strategies for the environmental impact. To advance this discussion, we analyze the 2019 Norwegian holiday travel survey to determine to what extent settlement size and regional density in Norway are associated with different holiday types that reflect different lifestyles and motivations. Using negative binomial and logistic regression while controlling for socioeconomic factors, we find that (1) it is not settlement size that influences the number of holiday trips, but whether a settlement lies in a dense county; (2) making nature getaways in Scandinavia and intercontinental trips are both positively associated with county density; (3) making city trips does not show a consistent link with spatial characteristics; (4) Mediterranean seaside holidays are typical for all Norwegians, no matter the place of residence. Our results indicate compensatory motivation behind nature getaways. However, dense everyday surroundings are not detrimental to visiting other densely populated areas on city vacations. The increased likelihood of intercontinental trips among people in dense areas may be explained by lifestyle and cosmopolitan attitudes rather than being a result of compensation.","PeriodicalId":509035,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":"81 25","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139784582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Adopting the Performance Margin in Horizontal Curve Design 在水平曲线设计中采用性能保证金

Transportation Research Record: Journal of the Transportation Research Board Pub Date : 2024-02-09 DOI: 10.1177/03611981241229090

Troy Jaisohn Kim, John B. Ferris

{"title":"Adopting the Performance Margin in Horizontal Curve Design","authors":"Troy Jaisohn Kim, John B. Ferris","doi":"10.1177/03611981241229090","DOIUrl":"https://doi.org/10.1177/03611981241229090","url":null,"abstract":"A vehicle negotiating a curve experiences a centripetal force that is partially supplied by the tire–pavement friction. The American Association of State Highway and Transportation Officials’ design handbook, A Policy on Geometric Design of Highways and Streets (“Green Book”), dictates the design of horizontal curve segments according to the side friction (demand) factor, which is a fraction of the available friction used during a maneuver. However, the Green Book casts the side friction factor not as a measure of tire–pavement friction but as a measure of lateral acceleration. In this way, the Green Book conflates these independent concepts (tire–pavement friction versus lateral acceleration). It is shown in this work that keeping these curve design parameters independent has meaningful benefits. A rigorous mathematical clarification of the differences among the side friction (demand) factor, lateral acceleration, and coefficient of friction is developed. It is shown that changing the coefficient of friction affects the side friction factor, but the opposite is not necessarily true. An alternate metric is proposed, the performance margin [Formula: see text], that has several advantages for assessing friction margins. Currently, horizontal curves are designed only with a lateral friction reserve. Excluding longitudinal dynamics may not be realistic given the manner in which drivers react in limit handling maneuvers. The [Formula: see text] accounts for both bidirectional dynamics and road geometry, and highlights regions where the Green Book’s standards are inconsistent with vehicle performance capabilities. The work concludes by posing recommendations aimed at implementing the [Formula: see text] in future Green Book editions.","PeriodicalId":509035,"journal":{"name":"Transportation Research Record: Journal of the Transportation Research Board","volume":" 40","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139790430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0