Transportation Engineering最新文献_第2页

Retrofitting existing rolling stock for wire-free travel: Exploring energy storage solutions for partial catenary-free light rail vehicle

Q1 Engineering

Transportation Engineering

Pub Date : 2024-12-21 DOI: 10.1016/j.treng.2024.100291

Anna SF Chang, Roy S Kalawsky

This paper investigates the retrofitting possibilities of equipping existing rolling stock with a catenary-free system for tramways and light rail networks. In this paper, the term 'tramway' includes light rail vehicle (LRV) as defined in EN17343. Installation, ongoing maintenance, and replacement of electric traction systems is a major cost for light rail operators. Installing visible overhead line equipment (OLE) in historical cities has always been a challenge. Past records have shown that the significant capital cost and the time it takes to approve a transport scheme are major barriers to the implementation of light rail vehicle proposals. This paper shows that adopting a catenary-free (wire-free) system can reduce the capital costs of light rail system design and construction, especially in the city centre. Battery-powered transport, once considered economically unfeasible, now shows promise even for large vehicles including urban and main line rail. A thorough analysis of various energy storage options has been investigated, including parameters such as maximum C-rate (the rate of time in which it takes to charge or discharge a battery), specific energy, energy density, safety, lifespan, and cost comparison. Findings have shown that the state-of-the-art solution using Lithium-ion Capacitors (LiC) increases the energy storage weight of the light rail vehicle by just 2.1 tons, equivalent to 3.5% of the light rail's total weight, making it a feasible option to retrofit. The hybrid energy solution contributes to higher energy and higher power densities, as well as longer cycle life compared to pure lithium-ion batteries. It's also more environmentally friendly. This work has implications for other all mass transit systems. The paper provides an innovative solution that bridges the gap between energy storage technology and rail transport design.

{"title":"Retrofitting existing rolling stock for wire-free travel: Exploring energy storage solutions for partial catenary-free light rail vehicle","authors":"Anna SF Chang, Roy S Kalawsky","doi":"10.1016/j.treng.2024.100291","DOIUrl":"10.1016/j.treng.2024.100291","url":null,"abstract":"<div><div>This paper investigates the retrofitting possibilities of equipping existing rolling stock with a catenary-free system for tramways and light rail networks. In this paper, the term 'tramway' includes light rail vehicle (LRV) as defined in EN17343. Installation, ongoing maintenance, and replacement of electric traction systems is a major cost for light rail operators. Installing visible overhead line equipment (OLE) in historical cities has always been a challenge. Past records have shown that the significant capital cost and the time it takes to approve a transport scheme are major barriers to the implementation of light rail vehicle proposals. This paper shows that adopting a catenary-free (wire-free) system can reduce the capital costs of light rail system design and construction, especially in the city centre. Battery-powered transport, once considered economically unfeasible, now shows promise even for large vehicles including urban and main line rail. A thorough analysis of various energy storage options has been investigated, including parameters such as maximum C-rate (the rate of time in which it takes to charge or discharge a battery), specific energy, energy density, safety, lifespan, and cost comparison. Findings have shown that the state-of-the-art solution using Lithium-ion Capacitors (LiC) increases the energy storage weight of the light rail vehicle by just 2.1 tons, equivalent to 3.5% of the light rail's total weight, making it a feasible option to retrofit. The hybrid energy solution contributes to higher energy and higher power densities, as well as longer cycle life compared to pure lithium-ion batteries. It's also more environmentally friendly. This work has implications for other all mass transit systems. The paper provides an innovative solution that bridges the gap between energy storage technology and rail transport design.</div></div>","PeriodicalId":34480,"journal":{"name":"Transportation Engineering","volume":"19 ","pages":"Article 100291"},"PeriodicalIF":0.0,"publicationDate":"2024-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Case study of the dynamics of thermal expansion of concrete in pavements of South Kazakhstan

Q1 Engineering

Transportation Engineering

Pub Date : 2024-12-20 DOI: 10.1016/j.treng.2024.100298

Zh.A. Shakhmov , K.K. Mukhambetkaliev , R.E. Lukpanov , D.S. Dyussembinov , A.A. Zhumagulova , D.O. Bazarbayev , A.E. Jexembayeva

This article explores the behaviour of concrete samples from road sections that have experienced warping due to temperature fluctuations. Warping refers to the curling of concrete slabs. The paper presents a novel approach to tracking the expansion and contraction of concrete joints over time. It analyses how the size and shape of concrete samples from cement-concrete (hereafter referred to as concrete) roads change under varying temperatures. Additionally, this study investigates the impact of temperature on concrete deformation. It was assumed that as the concrete's density and compressive strength increased, the linear expansion coefficient also increased. Furthermore, research has shown that this coefficient can vary along different axes within the concrete volume. This article describes the mechanism behind the deformations observed during the thermal expansion of concrete slabs and identifies the key factors influencing the buckling of concrete slabs as the air temperature rises. The temperature expansion may vary depending on the material's structure, as well as the constant polymorphic transformations of cement minerals within the concrete. These transformations are influenced by ambient temperature, humidity, and the presence of free lime. The factors affecting temperature expansion were determined to be the mineralogical composition of the cement, the concrete's strength class, and the cement content within the concrete.

{"title":"Case study of the dynamics of thermal expansion of concrete in pavements of South Kazakhstan","authors":"Zh.A. Shakhmov , K.K. Mukhambetkaliev , R.E. Lukpanov , D.S. Dyussembinov , A.A. Zhumagulova , D.O. Bazarbayev , A.E. Jexembayeva","doi":"10.1016/j.treng.2024.100298","DOIUrl":"10.1016/j.treng.2024.100298","url":null,"abstract":"<div><div>This article explores the behaviour of concrete samples from road sections that have experienced warping due to temperature fluctuations. Warping refers to the curling of concrete slabs. The paper presents a novel approach to tracking the expansion and contraction of concrete joints over time. It analyses how the size and shape of concrete samples from cement-concrete (hereafter referred to as concrete) roads change under varying temperatures. Additionally, this study investigates the impact of temperature on concrete deformation. It was assumed that as the concrete's density and compressive strength increased, the linear expansion coefficient also increased. Furthermore, research has shown that this coefficient can vary along different axes within the concrete volume. This article describes the mechanism behind the deformations observed during the thermal expansion of concrete slabs and identifies the key factors influencing the buckling of concrete slabs as the air temperature rises. The temperature expansion may vary depending on the material's structure, as well as the constant polymorphic transformations of cement minerals within the concrete. These transformations are influenced by ambient temperature, humidity, and the presence of free lime. The factors affecting temperature expansion were determined to be the mineralogical composition of the cement, the concrete's strength class, and the cement content within the concrete.</div></div>","PeriodicalId":34480,"journal":{"name":"Transportation Engineering","volume":"19 ","pages":"Article 100298"},"PeriodicalIF":0.0,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Save water to generate savings for bus operators: Facts, figures, practice and policy implications

Q1 Engineering

Transportation Engineering

Pub Date : 2024-12-15 DOI: 10.1016/j.treng.2024.100296

Maria Vittoria Corazza, Matthew Robinson, Alvin Benjamin Owusu-Afriyie

This paper aims to examine the frequently neglected concern of water usage in bus fleet maintenance, especially within the transit sector, which has traditionally prioritized energy and emissions management. The study seeks to assess the prospective savings derived from advanced water management technologies, including rainwater harvesting (RHR) and waxing, as part of the EC-funded LIFEH2OBUS initiative. The study employs a cost-benefit analysis (CBA) to compare business-as-usual (BAU) scenarios with the deployment of these technologies, evaluating their feasibility and efficacy in diminishing water consumption and expenses. Key findings indicate that the use of these technologies may decrease water usage by almost 70 %, resulting in an annual save of nearly 18 million liters for a fleet of 500 buses. Furthermore, the economic assessment reveals that both RHR and waxing technologies offer significant cost-saving potential relative to conventional water management techniques. Waxing, derived from the aviation industry, diminishes the need for frequent washing while providing enduring protection advantages for automobiles. The research indicates that implementing new water management technology can markedly improve the sustainability of bus fleet operations. The results indicate that these technologies ought to be adopted more extensively to realize both ecological and financial advantages. The policy implications highlighted include enhancing societal awareness and safeguarding the environment, revising regulatory frameworks, and promoting a "water culture" among transit operators to facilitate the widespread adoption of sustainable water practices in the transportation sector.

{"title":"Save water to generate savings for bus operators: Facts, figures, practice and policy implications","authors":"Maria Vittoria Corazza, Matthew Robinson, Alvin Benjamin Owusu-Afriyie","doi":"10.1016/j.treng.2024.100296","DOIUrl":"10.1016/j.treng.2024.100296","url":null,"abstract":"<div><div>This paper aims to examine the frequently neglected concern of water usage in bus fleet maintenance, especially within the transit sector, which has traditionally prioritized energy and emissions management. The study seeks to assess the prospective savings derived from advanced water management technologies, including rainwater harvesting (RHR) and waxing, as part of the EC-funded LIFEH2OBUS initiative. The study employs a cost-benefit analysis (CBA) to compare business-as-usual (BAU) scenarios with the deployment of these technologies, evaluating their feasibility and efficacy in diminishing water consumption and expenses. Key findings indicate that the use of these technologies may decrease water usage by almost 70 %, resulting in an annual save of nearly 18 million liters for a fleet of 500 buses. Furthermore, the economic assessment reveals that both RHR and waxing technologies offer significant cost-saving potential relative to conventional water management techniques. Waxing, derived from the aviation industry, diminishes the need for frequent washing while providing enduring protection advantages for automobiles. The research indicates that implementing new water management technology can markedly improve the sustainability of bus fleet operations. The results indicate that these technologies ought to be adopted more extensively to realize both ecological and financial advantages. The policy implications highlighted include enhancing societal awareness and safeguarding the environment, revising regulatory frameworks, and promoting a \"water culture\" among transit operators to facilitate the widespread adoption of sustainable water practices in the transportation sector.</div></div>","PeriodicalId":34480,"journal":{"name":"Transportation Engineering","volume":"19 ","pages":"Article 100296"},"PeriodicalIF":0.0,"publicationDate":"2024-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Aggregate crash prediction model based on gravity model: Introducing crash risk distribution concept

Q1 Engineering

Transportation Engineering

Pub Date : 2024-12-14 DOI: 10.1016/j.treng.2024.100297

Saman Dabbaghfeizi , Ali Naderan , Ali Tavakoli-Kashani

Crash prediction models (CPMs) can be valuable for future transportation planning decisions. This study aims to develop CPMs based on the trip distribution step of the common four-step demand models. For this purpose, the Gravity Model is used. For model calibration, the frequency of severe crashes (including the total of fatal and injury crashes) between each origin-destination (OD) pair of traffic analysis zones (TAZs) in the city of Qom in Iran has been used as the dependent variable. The number of trip distributions by purpose, traffic characteristics on the links, and road network characteristics has been used as the explanatory variables. The model validation results show a significant relationship between the mentioned variables. Therefore, in addition to predicting the crash frequency according to trip number changes in the future, the developed model in this study determines the relationship between the crash frequency with the OD characteristics of the trips that lead to crashes. This makes it possible to evaluate the impact of different travel demand management scenarios on safety so that the crash risk (i.e., crash occurrence probability) of trips distributed between TAZs is identified and prioritized and can be planned to improve or reduced them.

{"title":"Aggregate crash prediction model based on gravity model: Introducing crash risk distribution concept","authors":"Saman Dabbaghfeizi , Ali Naderan , Ali Tavakoli-Kashani","doi":"10.1016/j.treng.2024.100297","DOIUrl":"10.1016/j.treng.2024.100297","url":null,"abstract":"<div><div>Crash prediction models (CPMs) can be valuable for future transportation planning decisions. This study aims to develop CPMs based on the trip distribution step of the common four-step demand models. For this purpose, the Gravity Model is used. For model calibration, the frequency of severe crashes (including the total of fatal and injury crashes) between each origin-destination (OD) pair of traffic analysis zones (TAZs) in the city of Qom in Iran has been used as the dependent variable. The number of trip distributions by purpose, traffic characteristics on the links, and road network characteristics has been used as the explanatory variables. The model validation results show a significant relationship between the mentioned variables. Therefore, in addition to predicting the crash frequency according to trip number changes in the future, the developed model in this study determines the relationship between the crash frequency with the OD characteristics of the trips that lead to crashes. This makes it possible to evaluate the impact of different travel demand management scenarios on safety so that the crash risk (i.e., crash occurrence probability) of trips distributed between TAZs is identified and prioritized and can be planned to improve or reduced them.</div></div>","PeriodicalId":34480,"journal":{"name":"Transportation Engineering","volume":"19 ","pages":"Article 100297"},"PeriodicalIF":0.0,"publicationDate":"2024-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Properties of reclaimed asphalt pavement with Bio-Heating Oil as a rejuvenator considering ageing

Q1 Engineering

Transportation Engineering

Pub Date : 2024-12-10 DOI: 10.1016/j.treng.2024.100295

Silvino Dias Capitão , Luís Guilherme de Picado-Santos , Arminda Maria Marques Almeida

This paper studies the use of Bio Heating Oil (BHO), a waste derived from biodiesel production, as the rejuvenator of aged bitumen of reclaimed asphalt pavement (RAP). The BHO was added to the blend during the asphalt concrete mixing process (dry process). The study assessed whether BHO is suitable to rejuvenate a high percentage of RAP (60 % or 80 %) to produce hot- and warm-mix asphalt concrete adequate for medium/low-traffic roads. The analysis involved the laboratory evaluation of volumetric and Marshall properties and the assessment of mechanical performance. The study also evaluated workability in a gyratory compactor, rutting resistance using wheel tracking tests, and resistance to water damage by indirect tensile strength testing. Because durability after long-term ageing may be an issue for the studied mixtures, the laboratory testing program assessed stiffness and resistance to fatigue cracking in four-point bending tests performed before and after applying a pre-validated ageing protocol to the specimens. The study also evaluated slabs' texture depth and skid resistance with and without ageing. The findings confirm that hot-mix and warm-mix asphalt concrete with 60 % and 80 % RAP, respectively, and 10 % of BHO by mass of bitumen fulfil the requirements for use in medium/low-traffic roadways regarding water sensitivity, stiffness, resistance to permanent deformation and fatigue, and surface performance, even after long-term ageing.

{"title":"Properties of reclaimed asphalt pavement with Bio-Heating Oil as a rejuvenator considering ageing","authors":"Silvino Dias Capitão , Luís Guilherme de Picado-Santos , Arminda Maria Marques Almeida","doi":"10.1016/j.treng.2024.100295","DOIUrl":"10.1016/j.treng.2024.100295","url":null,"abstract":"<div><div>This paper studies the use of Bio Heating Oil (BHO), a waste derived from biodiesel production, as the rejuvenator of aged bitumen of reclaimed asphalt pavement (RAP). The BHO was added to the blend during the asphalt concrete mixing process (dry process). The study assessed whether BHO is suitable to rejuvenate a high percentage of RAP (60 % or 80 %) to produce hot- and warm-mix asphalt concrete adequate for medium/low-traffic roads. The analysis involved the laboratory evaluation of volumetric and Marshall properties and the assessment of mechanical performance. The study also evaluated workability in a gyratory compactor, rutting resistance using wheel tracking tests, and resistance to water damage by indirect tensile strength testing. Because durability after long-term ageing may be an issue for the studied mixtures, the laboratory testing program assessed stiffness and resistance to fatigue cracking in four-point bending tests performed before and after applying a pre-validated ageing protocol to the specimens. The study also evaluated slabs' texture depth and skid resistance with and without ageing. The findings confirm that hot-mix and warm-mix asphalt concrete with 60 % and 80 % RAP, respectively, and 10 % of BHO by mass of bitumen fulfil the requirements for use in medium/low-traffic roadways regarding water sensitivity, stiffness, resistance to permanent deformation and fatigue, and surface performance, even after long-term ageing.</div></div>","PeriodicalId":34480,"journal":{"name":"Transportation Engineering","volume":"19 ","pages":"Article 100295"},"PeriodicalIF":0.0,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mobility as a Service: Insights from pilot studies across different Italian settings

Q1 Engineering

Transportation Engineering

Pub Date : 2024-12-01 DOI: 10.1016/j.treng.2024.100294

Italo Meloni , Giuseppe Musolino , Francesco Piras , Corrado Rindone , Francesco Russo , Eleonora Sottile , Antonino Vitetta

Mobility as a Service (MaaS) has been tested in numerous cities and enables users to travel within an integrated system of collective and shared transport services, with a single travel package or bundle, giving them the ability to plan, book and pay for a trip using a unique technological platform. At this stage of the MaaS system experimentation, a detailed analysis on a small scale enables, through the understanding of the mechanisms governing travel choices, the planning of a MaaS service on a large scale that has the right flexibility to adapt to different territorial contexts. The paper reports the main findings of a study carried out as part of a national research project funded by the Italian Ministry of University and Research. Within this project, evaluation methodologies were developed (Technology Acceptance Model, Revealed Preferences and Intended Preference surveys), pilot surveys were conducted on samples of potential users, and the results were analysed and compared to assess the potential activation of a MaaS and to estimate its impacts on mobility.

Two pilot experiments and an extended test, with a sample of almost 200 users, were carried out in different territorial contexts in Italy: the metropolitan areas of Reggio Calabria and Messina, the extra-urban area of Gioia Tauro and the urban area of the metropolitan city of Cagliari. The activities should be regarded as preliminary and indispensable stage for the design of more extensive investigations, as well as for the planning of a possible MaaS system in the areas examined.

{"title":"Mobility as a Service: Insights from pilot studies across different Italian settings","authors":"Italo Meloni , Giuseppe Musolino , Francesco Piras , Corrado Rindone , Francesco Russo , Eleonora Sottile , Antonino Vitetta","doi":"10.1016/j.treng.2024.100294","DOIUrl":"10.1016/j.treng.2024.100294","url":null,"abstract":"<div><div>Mobility as a Service (MaaS) has been tested in numerous cities and enables users to travel within an integrated system of collective and shared transport services, with a single travel package or bundle, giving them the ability to plan, book and pay for a trip using a unique technological platform. At this stage of the MaaS system experimentation, a detailed analysis on a small scale enables, through the understanding of the mechanisms governing travel choices, the planning of a MaaS service on a large scale that has the right flexibility to adapt to different territorial contexts. The paper reports the main findings of a study carried out as part of a national research project funded by the Italian Ministry of University and Research. Within this project, evaluation methodologies were developed (Technology Acceptance Model, Revealed Preferences and Intended Preference surveys), pilot surveys were conducted on samples of potential users, and the results were analysed and compared to assess the potential activation of a MaaS and to estimate its impacts on mobility.</div><div>Two pilot experiments and an extended test, with a sample of almost 200 users, were carried out in different territorial contexts in Italy: the metropolitan areas of Reggio Calabria and Messina, the extra-urban area of Gioia Tauro and the urban area of the metropolitan city of Cagliari. The activities should be regarded as preliminary and indispensable stage for the design of more extensive investigations, as well as for the planning of a possible MaaS system in the areas examined.</div></div>","PeriodicalId":34480,"journal":{"name":"Transportation Engineering","volume":"18 ","pages":"Article 100294"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Importance of geotechnical diagnosis in railway management: A review

Q1 Engineering

Transportation Engineering

Pub Date : 2024-12-01 DOI: 10.1016/j.treng.2024.100293

Jorge Rojas Vivanco , Pierre Breul , Aurélie TALON , Miguel Angel Benz-Navarrete , Sébastien Barbier , Younes Haddani

Railway tracks, like all civil works, experience degradation after being put into service, thus losing their initial design conditions. This degradation manifests itself mainly through misalignment and specific deterioration mechanisms of each component, which reduces safety and comfort during the passage of trains. In order to maintain their operational capabilities or prolong their service life, continuous monitoring, diagnosis and maintenance processes are carried out. These actions aim to restore the physical, mechanical and geometrical properties necessary for track operation.

In practice, rail managers often employ hegemonic techniques such as geometric measurements to detect defects and routine maintenance to realign, known as tamping. Although these practices have proven to be effective, in some cases they do not technically and economically competently solve the root problem. For this reason, diagnosis should be multidisciplinary and incorporate various disciplines associated with the track components.

This paper aims to highlight the importance and impact of geotechnical diagnosis in the management of railway networks. To achieve this, the article has the following structure: (a) Railway track components: the main elements of the track are described and the role of geotechnical components in the stability of the infrastructure is highlighted, (b) Track degradation: The main deterioration of the track, such as loss of geometry, and its relation to the wear of the geotechnical elements are addressed, (c) Monitoring and monitoring: the most commonly used geotechnical inspection methods and their effectiveness in the analysis of granular material are presented, (d) Geotechnical diagnosis: Current maintenance management is analyzed and guidelines for a comprehensive diagnosis are suggested, highlighting cases where poor assessment has generated problems, (e) Maintenance techniques: Preservation methods are reviewed, stressing the importance of accurate diagnosis for their effectiveness, and (f) Future perspectives: Trends such as the use of artificial intelligence and advanced data management in the railway sector are explored.

{"title":"Importance of geotechnical diagnosis in railway management: A review","authors":"Jorge Rojas Vivanco , Pierre Breul , Aurélie TALON , Miguel Angel Benz-Navarrete , Sébastien Barbier , Younes Haddani","doi":"10.1016/j.treng.2024.100293","DOIUrl":"10.1016/j.treng.2024.100293","url":null,"abstract":"<div><div>Railway tracks, like all civil works, experience degradation after being put into service, thus losing their initial design conditions. This degradation manifests itself mainly through misalignment and specific deterioration mechanisms of each component, which reduces safety and comfort during the passage of trains. In order to maintain their operational capabilities or prolong their service life, continuous monitoring, diagnosis and maintenance processes are carried out. These actions aim to restore the physical, mechanical and geometrical properties necessary for track operation.</div><div>In practice, rail managers often employ hegemonic techniques such as geometric measurements to detect defects and routine maintenance to realign, known as tamping. Although these practices have proven to be effective, in some cases they do not technically and economically competently solve the root problem. For this reason, diagnosis should be multidisciplinary and incorporate various disciplines associated with the track components.</div><div>This paper aims to highlight the importance and impact of geotechnical diagnosis in the management of railway networks. To achieve this, the article has the following structure: (a) Railway track components: the main elements of the track are described and the role of geotechnical components in the stability of the infrastructure is highlighted, (b) Track degradation: The main deterioration of the track, such as loss of geometry, and its relation to the wear of the geotechnical elements are addressed, (c) Monitoring and monitoring: the most commonly used geotechnical inspection methods and their effectiveness in the analysis of granular material are presented, (d) Geotechnical diagnosis: Current maintenance management is analyzed and guidelines for a comprehensive diagnosis are suggested, highlighting cases where poor assessment has generated problems, (e) Maintenance techniques: Preservation methods are reviewed, stressing the importance of accurate diagnosis for their effectiveness, and (f) Future perspectives: Trends such as the use of artificial intelligence and advanced data management in the railway sector are explored.</div></div>","PeriodicalId":34480,"journal":{"name":"Transportation Engineering","volume":"18 ","pages":"Article 100293"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143149204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimizing renewable energy-based plug-in hybrid electric vehicle charging stations for sustainable transportation in India 优化基于可再生能源的插电式混合动力汽车充电站，实现印度的可持续交通

Q1 Engineering

Transportation Engineering

Pub Date : 2024-12-01 DOI: 10.1016/j.treng.2024.100292

Anandan P , Siow Chun Lim , Anbuselvan N

India's burgeoning population necessitates innovative transportation solutions, with electric vehicles (EVs) emerging as a locally viable and urgent need. However, a significant obstacle lies in the improper deployment of charging stations, which strains the power distribution system. Recognizing the environmental benefits of Renewable Energy Sources (RES), high-priority buses are now equipped with Plug-in Hybrid Electric Vehicle (PHEV) charging stations, bolstering effective utilization. This study leverages meta-heuristic optimization techniques to propose an efficient allocation strategy for PHEV charging stations powered by RES. The core objective is to establish a cost-effective charging infrastructure while upholding the effective integrity of the network in distribution system. To address these challenges, the study employs meta-heuristic optimization algorithms and optimizes forecasting around sustainable energy systems to achieve desired output. Consequently, the research introduces a novel approach, conceptualizing the distribution of optimal charging stations as a multi-objective problem with added parameters. Furthermore, this study tackles the RES PHEV and charging station site challenge by introducing the innovative Walrus Optimization Algorithm (WaOA), which effectively overcomes issues related to slow convergence and local optima. Experimental findings demonstrate the superiority of the proposed model in terms of minimizing the cost function. This research offers a promising pathway toward sustainable transportation in India's evolving landscape.

印度迅速增长的人口需要创新的交通解决方案，电动汽车（ev）正在成为当地可行和迫切的需求。然而，一个重要的障碍是充电站的部署不当，这给配电系统带来了压力。认识到可再生能源（RES）的环境效益，高优先级公交车现在配备了插电式混合动力汽车（PHEV）充电站，提高了有效利用。本研究利用元启发式优化技术，提出了一种高效的插电式混合动力充电站配置策略，其核心目标是建立一个具有成本效益的充电基础设施，同时保持配电系统网络的有效完整性。为了应对这些挑战，该研究采用了元启发式优化算法，并围绕可持续能源系统优化预测，以实现预期的输出。因此，该研究引入了一种新颖的方法，将最优充电站的分布概念化为一个带有附加参数的多目标问题。此外，本文还引入了创新的海象优化算法（Walrus Optimization Algorithm, WaOA），有效地解决了RES插电式混合动力汽车和充电站选址问题，有效地克服了收敛速度慢和局部最优的问题。实验结果证明了该模型在最小化成本函数方面的优越性。这项研究为在印度不断变化的景观中实现可持续交通提供了一条有希望的途径。

{"title":"Optimizing renewable energy-based plug-in hybrid electric vehicle charging stations for sustainable transportation in India","authors":"Anandan P , Siow Chun Lim , Anbuselvan N","doi":"10.1016/j.treng.2024.100292","DOIUrl":"10.1016/j.treng.2024.100292","url":null,"abstract":"<div><div>India's burgeoning population necessitates innovative transportation solutions, with electric vehicles (EVs) emerging as a locally viable and urgent need. However, a significant obstacle lies in the improper deployment of charging stations, which strains the power distribution system. Recognizing the environmental benefits of Renewable Energy Sources (RES), high-priority buses are now equipped with Plug-in Hybrid Electric Vehicle (PHEV) charging stations, bolstering effective utilization. This study leverages meta-heuristic optimization techniques to propose an efficient allocation strategy for PHEV charging stations powered by RES. The core objective is to establish a cost-effective charging infrastructure while upholding the effective integrity of the network in distribution system. To address these challenges, the study employs meta-heuristic optimization algorithms and optimizes forecasting around sustainable energy systems to achieve desired output. Consequently, the research introduces a novel approach, conceptualizing the distribution of optimal charging stations as a multi-objective problem with added parameters. Furthermore, this study tackles the RES PHEV and charging station site challenge by introducing the innovative Walrus Optimization Algorithm (WaOA), which effectively overcomes issues related to slow convergence and local optima. Experimental findings demonstrate the superiority of the proposed model in terms of minimizing the cost function. This research offers a promising pathway toward sustainable transportation in India's evolving landscape.</div></div>","PeriodicalId":34480,"journal":{"name":"Transportation Engineering","volume":"18 ","pages":"Article 100292"},"PeriodicalIF":0.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142756878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Improving powertrain efficiency through torque modulation techniques in single and dual motor electric vehicles 通过单电机和双电机电动汽车的扭矩调节技术提高动力总成效率

Q1 Engineering

Transportation Engineering

Pub Date : 2024-11-10 DOI: 10.1016/j.treng.2024.100289

Y. Xu , P. Ingelström , A. Kersten , A. Andersson , S. Klacar , S. George , D. Sedarsky

Battery Electric Vehicles (BEVs) typically experience reduced powertrain energy efficiency under low-torque operating conditions. This issue can be mitigated by torque modulation, i.e., alternating driver torque demand between zero and an appropriate value. This paper aims to maximize the efficiency improvement of torque modulation and investigate its potential in two powertrain topologies: single and dual motor powertrains. To this end, optimal modulation strategies are proposed for both powertrains, considering overall powertrain energy losses and specific powertrain characteristics. Additionally, the adverse impact on driver comfort and powertrain durability due to the pulsating torque is examined. The results suggest that the proposed optimal modulation strategies can enhance powertrain efficiency while maintaining acceptable levels of driver comfort and powertrain durability. In addition, complementary modulation and torque distribution can be applied in the dual motor powertrain to provide further energy-saving potential and reduced impact on driver comfort.

在低扭矩运行条件下，电池电动汽车（BEV）的动力总成能效通常会降低。这一问题可以通过扭矩调制来缓解，即在零和适当值之间交替调节驱动扭矩需求。本文旨在最大限度地提高扭矩调制的效率，并研究其在两种动力总成拓扑结构（单电机和双电机动力总成）中的潜力。为此，考虑到动力总成的整体能量损失和动力总成的具体特性，为这两种动力总成提出了最佳调制策略。此外，还研究了脉动扭矩对驾驶舒适性和动力总成耐用性的不利影响。结果表明，所提出的最佳调制策略可以提高动力总成效率，同时保持可接受的驾驶舒适性和动力总成耐用性水平。此外，在双电机动力总成中还可采用互补调制和扭矩分配，以进一步提高节能潜力并减少对驾驶员舒适性的影响。

{"title":"Improving powertrain efficiency through torque modulation techniques in single and dual motor electric vehicles","authors":"Y. Xu , P. Ingelström , A. Kersten , A. Andersson , S. Klacar , S. George , D. Sedarsky","doi":"10.1016/j.treng.2024.100289","DOIUrl":"10.1016/j.treng.2024.100289","url":null,"abstract":"<div><div>Battery Electric Vehicles (BEVs) typically experience reduced powertrain energy efficiency under low-torque operating conditions. This issue can be mitigated by torque modulation, i.e., alternating driver torque demand between zero and an appropriate value. This paper aims to maximize the efficiency improvement of torque modulation and investigate its potential in two powertrain topologies: single and dual motor powertrains. To this end, optimal modulation strategies are proposed for both powertrains, considering overall powertrain energy losses and specific powertrain characteristics. Additionally, the adverse impact on driver comfort and powertrain durability due to the pulsating torque is examined. The results suggest that the proposed optimal modulation strategies can enhance powertrain efficiency while maintaining acceptable levels of driver comfort and powertrain durability. In addition, complementary modulation and torque distribution can be applied in the dual motor powertrain to provide further energy-saving potential and reduced impact on driver comfort.</div></div>","PeriodicalId":34480,"journal":{"name":"Transportation Engineering","volume":"18 ","pages":"Article 100289"},"PeriodicalIF":0.0,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A dynamic boundary condition finite difference model for predicting pavement profile temperatures: Development and validation 用于预测路面温度的动态边界条件有限差分模型：开发与验证

Q1 Engineering

Transportation Engineering

Pub Date : 2024-11-10 DOI: 10.1016/j.treng.2024.100287

Zahra Motamedi , Tarun Bansal , Hans Mattsson , Jan Åström , Johan Casselgren

The appearance of ground frost is of vital importance in construction and maintenance of roads in cold climates. Frost often causes ground heave and subsequent road damage, which must be taken into account in designing the road structure. Frost depth, pavement temperature, and freezing/thawing cycles are also important for estimating the frequency of road maintenance and treatment. Various analytical, numerical, and empirical models have been developed to estimate the surface temperature of the pavement and to model the heat flow in the underlying layers. The pavement surface experiences a variety of intricate nonlinear heat transfer mechanisms during winter, making it challenging to accurately model the surface boundary. Dynamic variation of parameters such as cloud cover and traffic density during the modeling period introduces additional complexity. To address this challenge, we have established an experimental setup in Luleå, Sweden, to measure pavement profile temperatures during the winter season. Additionally, we have developed a Finite Difference Model that utilizes local weather data including dynamic cloud cover, and which also takes traffic into account. The experimental and simulation findings demonstrate how the impact of surface temperature fluctuations diminishes and, more or less, vanishes for depths more than 55 [cm] below the pavement surface. The Finite Difference Model presented in this study exhibits the ability to forecast the pavement profile temperatures, including the surface temperature based on weather conditions, with acceptable precision for at least 3 days. As a consequence, a reasonable assessment of pavement layer conditions appears feasible based on local weather conditions, and the model can serve as a useful tool for planning road maintenance and construction in cold regions.

地面霜冻的出现对于寒冷气候条件下的道路建设和维护至关重要。霜冻通常会导致地面起伏，进而造成道路损坏，在设计道路结构时必须考虑到这一点。霜冻深度、路面温度和冻融循环对于估算道路维护和处理的频率也很重要。目前已开发出各种分析、数值和经验模型，用于估算路面表面温度和建立底层热流模型。路面表面在冬季会经历各种错综复杂的非线性传热机制，因此对路面边界进行精确建模极具挑战性。建模期间云层和交通密度等参数的动态变化也带来了额外的复杂性。为了应对这一挑战，我们在瑞典吕勒奥建立了一个实验装置，用于测量冬季路面的温度。此外，我们还开发了一个有限差分模型，该模型利用了包括动态云层在内的当地天气数据，并将交通情况考虑在内。实验和模拟结果表明，表面温度波动的影响会逐渐减小，当路面以下深度超过 55 [cm] 时，这种影响或多或少会消失。本研究中提出的有限差分模型能够预测路面剖面温度，包括基于天气条件的表面温度，精度至少为 3 天。因此，根据当地天气条件对路面层状况进行合理评估似乎是可行的，该模型可作为寒冷地区道路维护和建设规划的有用工具。

{"title":"A dynamic boundary condition finite difference model for predicting pavement profile temperatures: Development and validation","authors":"Zahra Motamedi , Tarun Bansal , Hans Mattsson , Jan Åström , Johan Casselgren","doi":"10.1016/j.treng.2024.100287","DOIUrl":"10.1016/j.treng.2024.100287","url":null,"abstract":"<div><div>The appearance of ground frost is of vital importance in construction and maintenance of roads in cold climates. Frost often causes ground heave and subsequent road damage, which must be taken into account in designing the road structure. Frost depth, pavement temperature, and freezing/thawing cycles are also important for estimating the frequency of road maintenance and treatment. Various analytical, numerical, and empirical models have been developed to estimate the surface temperature of the pavement and to model the heat flow in the underlying layers. The pavement surface experiences a variety of intricate nonlinear heat transfer mechanisms during winter, making it challenging to accurately model the surface boundary. Dynamic variation of parameters such as cloud cover and traffic density during the modeling period introduces additional complexity. To address this challenge, we have established an experimental setup in Luleå, Sweden, to measure pavement profile temperatures during the winter season. Additionally, we have developed a Finite Difference Model that utilizes local weather data including dynamic cloud cover, and which also takes traffic into account. The experimental and simulation findings demonstrate how the impact of surface temperature fluctuations diminishes and, more or less, vanishes for depths more than 55 [cm] below the pavement surface. The Finite Difference Model presented in this study exhibits the ability to forecast the pavement profile temperatures, including the surface temperature based on weather conditions, with acceptable precision for at least 3 days. As a consequence, a reasonable assessment of pavement layer conditions appears feasible based on local weather conditions, and the model can serve as a useful tool for planning road maintenance and construction in cold regions.</div></div>","PeriodicalId":34480,"journal":{"name":"Transportation Engineering","volume":"18 ","pages":"Article 100287"},"PeriodicalIF":0.0,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0