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Open Access
Article
Publication date: 31 October 2023

Hongping Xing, Yu Liu and Xiaodan Sun

The smoothness of the high-speed railway (HSR) on the bridge may exceed the allowable standard when an earthquake causes vibrations for HSR bridges, which may threaten the safety…

Abstract

Purpose

The smoothness of the high-speed railway (HSR) on the bridge may exceed the allowable standard when an earthquake causes vibrations for HSR bridges, which may threaten the safety of running trains. Indeed, few studies have evaluated the exceeding probability of rail displacement exceeding the allowable standard. The purposes of this article are to provide a method for investigating the exceeding probability of the rail displacement of HSRs under seismic excitation and to calculate the exceeding probability.

Design/methodology/approach

In order to investigate the exceeding probability of the rail displacement under different seismic excitations, the workflow of analyzing the smoothness of the rail based on incremental dynamic analysis (IDA) is proposed, and the intensity measure and limit state for the exceeding probability analysis of HSRs are defined. Then a finite element model (FEM) of an assumed HSR track-bridge system is constructed, which comprises a five-span simply-supported girder bridge supporting a finite length CRTS II ballastless track. Under different seismic excitations, the seismic displacement response of the rail is calculated; the character of the rail displacement is analyzed; and the exceeding probability of the rail vertical displacement exceeding the allowable standard (2mm) is investigated.

Findings

The results show that: (1) The bridge-abutment joint position may form a step-like under seismic excitation, threatening the running safety of high-speed trains under seismic excitations, and the rail displacements at mid-span positions are bigger than that at other positions on the bridge. (2) The exceeding probability of rail displacement is up to about 44% when PGA = 0.01g, which is the level-five risk probability and can be described as 'very likely to happen'. (3) The exceeding probability of the rail at the mid-span positions is bigger than that above other positions of the bridge, and the mid-span positions of the track-bridge system above the bridge may be the most hazardous area for the running safety of trains under seismic excitation when high-speed trains run on bridges.

Originality/value

The work extends the seismic hazardous analysis of HSRs and would lead to a better understanding of the exceeding probability for the rail of HSRs under seismic excitations and better references for the alert of the HSR operation.

Open Access
Article
Publication date: 9 May 2022

Guolong Li, Mangmang Gao, Jingjing Yang, Yunlu Wang and Xueming Cao

This study aims to propose a vertical coupling dynamic analysis method of vehicle–track–substructure based on forced vibration and use this method to analyze the influence on the…

Abstract

Purpose

This study aims to propose a vertical coupling dynamic analysis method of vehicle–track–substructure based on forced vibration and use this method to analyze the influence on the dynamic response of track and vehicle caused by local fastener failure.

Design/methodology/approach

The track and substructure are decomposed into the rail subsystem and substructure subsystem, in which the rail subsystem is composed of two layers of nodes corresponding to the upper rail and the lower fastener. The rail is treated as a continuous beam with elastic discrete point supports, and spring-damping elements are used to simulate the constraints between rail and fastener. Forced displacement and forced velocity are used to deal with the effect of the substructure on the rail system, while the external load is used to deal with the reverse effect. The fastener failure is simulated with the methods that cancel the forced vibration transmission, namely take no account of the substructure–rail interaction at that position.

Findings

The dynamic characteristics of the infrastructure with local diseases can be accurately calculated by using the proposed method. Local fastener failure will slightly affect the vibration of substructure and carbody, but it will significantly intensify the vibration response between wheel and rail. The maximum vertical displacement and the maximum vertical vibration acceleration of rail is 2.94 times and 2.97 times the normal value, respectively, under the train speed of 350 km·h−1. At the same time, the maximum wheel–rail force and wheel load reduction rate increase by 22.0 and 50.2%, respectively, from the normal value.

Originality/value

This method can better reveal the local vibration conditions of the rail and easily simulate the influence of various defects on the dynamic response of the coupling system.

Details

Railway Sciences, vol. 1 no. 2
Type: Research Article
ISSN: 2755-0907

Keywords

Open Access
Article
Publication date: 19 May 2022

Wenhua Guo, Xinmin Hong and Chunxia Chen

This paper aims to study the influence of aerodynamics force of trains passing each other on the dynamic response of vehicle bridge coupling system based on numerical simulation…

Abstract

Purpose

This paper aims to study the influence of aerodynamics force of trains passing each other on the dynamic response of vehicle bridge coupling system based on numerical simulation and multi-body dynamics and put forward the speed threshold for safe running of train under different crosswind speeds.

Design/methodology/approach

The computational fluid dynamics method is adopted to simulate the aerodynamic force in the whole process of train passing each other by using dynamic grid technology. The dynamic model of vehicle-bridge coupling system is established considering the effects of aerodynamic force of train passing each other under crosswind, the dynamic response of train intersection on the bridge under crosswind is computed and the running safety of the train is evaluated.

Findings

The aerodynamic force of trains' intersection has little effects on the derailment factor, lateral wheel-rail force and vertical acceleration of train, but it increases the offload factor of train and significantly increases the lateral acceleration of train. The crosswind has a significant effect on increasing the derailment factor, lateral wheel-rail force and offload factor of train. The offload factor of train is the key factor to control the threshold of train speed. The impact of the aerodynamic force of trains' intersection on running safety cannot be ignored. When the extreme values of crosswind wind speed are 15 m·s−1, 20 m·s−1 and 25 m·s−1, respectively, the corresponding speed thresholds for safe running of train are 350 km·h−1, 275 km·h−1 and 200 km·h−1, respectively.

Originality/value

The research can provide a more precise numerical method to study the running safety of high-speed trains under the aerodynamic effect of trains passing each other on bridge in crosswind.

Details

Railway Sciences, vol. 1 no. 2
Type: Research Article
ISSN: 2755-0907

Keywords

Open Access
Article
Publication date: 11 July 2023

Harvey C. Perkins, Michael Mackay and Jude Wilson

The authors report a study of heritage conservation linked to rural small-town regeneration in Aotearoa New Zealand. The purpose of this study is to answer the question: how, with…

Abstract

Purpose

The authors report a study of heritage conservation linked to rural small-town regeneration in Aotearoa New Zealand. The purpose of this study is to answer the question: how, with limited local resources, do the residents and administrators of small settlements conserve historic heritage in the processes of rural regeneration?

Design/methodology/approach

This research is based on an analysis of physical heritage objects (buildings, artefacts and landscapes), associated regulatory arrangements, archival material, news media reporting, community group newsletters and photography. The authors use the river-side town of Rakaia and its environs in Te Waipounamu/the South Island of Aotearoa New Zealand to answer the research question.

Findings

This research found that in a context of limited resources, volunteers, supported by small businesses and local and central government, can contribute positively to the conservation and interpretation of heritage as part of wider rural regeneration activities.

Originality/value

There is only limited writing on the links between heritage conservation, rural regeneration and the development of small towns. To advance the debate, the authors combine ideas about community-led heritage conservation and management with concepts drawn from rural studies, particularly the multifunctional rural space paradigm. This allows us to explore heritage conservation in a context of rapid rural change.

Details

Journal of Place Management and Development, vol. 16 no. 3
Type: Research Article
ISSN: 1753-8335

Keywords

Open Access
Article
Publication date: 31 December 2004

Michael S. Bomba and Robert Harrison

East Asia's emergence as the forthcoming center of global manufacturing is leading nations in the region to reconsider their current and future role in the world economy. For its…

Abstract

East Asia's emergence as the forthcoming center of global manufacturing is leading nations in the region to reconsider their current and future role in the world economy. For its part, the Republic of Korea is pursuing a strategy to transform the country into the business hub of Northeast Asia. A central aspect in this strategy is the development of a regional “Pentaport” in the city of lncheon, which will consist of five components: an airport, a seaport, a business port, a technoport, and a leisure port. Hopefully, the Port of lncheon will be able to specialize in moving both coastal cargoes and transshipment cargoes to and from China and Japan using Short Sea Shipping (SSS). The first section of this paper provides an analysis of recent trade patterns between the Asian countries of the Asian-Pacific Economic Cooperation (APEC) agreement and the United States, with an emphasis on the Republic of Korea. The second part of the paper discusses current intermodal coastal shipping practices in the United States along the Gulf of Mexico and offers suggestions to the developers of Korea s Pentaport initiative; based upon observations in the United States, to maximize the likelihood of their success.

Details

Journal of International Logistics and Trade, vol. 2 no. 2
Type: Research Article
ISSN: 1738-2122

Keywords

Open Access
Article
Publication date: 15 June 2022

Md Mamunur Rashid

This paper presents comparative studies of modern transportation systems in the Bengal Delta and British Borneo. To meet the demands of the new modes of resource extraction, the…

Abstract

This paper presents comparative studies of modern transportation systems in the Bengal Delta and British Borneo. To meet the demands of the new modes of resource extraction, the British colonial rulers introduced a new transportation system in both regions and built roads, railways, and navigational routes connecting major commercial and political centers. There has been little research into the historical connections between modern transportation and environmental changes in colonial South Asia and Malaysia. When modern transportation was introduced, environmental consequences were rarely considered. As a result, significant ecological changes and declines were unintentionally caused. The environmental changes brought about by these transportation systems in these two regions were not the same one from the other. For example, railroad construction harmed the plains and waterways in the Bengal Delta, whereas, in British Borneo, rubber plantations for the global market harmed the rainforests.

Details

Southeast Asia: A Multidisciplinary Journal, vol. 22 no. 1
Type: Research Article
ISSN: 1819-5091

Keywords

Open Access
Article
Publication date: 30 January 2005

Peter J. Rimmer and Claude Comtois

The growth of China’s economy during the 1990s has both shaped and reflected changes in the span and function of the country’s shipping connections both within Asia and with the…

Abstract

The growth of China’s economy during the 1990s has both shaped and reflected changes in the span and function of the country’s shipping connections both within Asia and with the rest of the world. Although sea-land developments within China have been studied, less attention has been paid to the wider global implications stemming from the transformation of the country’s maritime geography during a decade of further market reforms and greater integration into the world economy. Consequently, there is a need to comprehend how China’s state-owned shipping industry has been reorganized during the 1990s to meet the new requirements, with special reference to the country’s liner shipping connections between and within Asia respectively. More purposely, these topics are addressed by examining changes in the organization, approach and set of connections of the state-owned China Ocean Shipping (Group) Company (Cosco) and its post-1993 offshoot COSCO Container Lines Company Ltd (Coscon). This review provides a springboard for a detailed analysis of shifts in both extra- and intra-Asian shipping patterns between 1990 and 2000 and consideration of their strategic implications. Finally, short-sea shipping is defined and the phenomenon’s operational strengths and weaknesses discussed.

Details

Journal of International Logistics and Trade, vol. 3 no. 1
Type: Research Article
ISSN: 1738-2122

Keywords

Open Access
Article
Publication date: 21 May 2018

Zul-Atfi Bin Ismail

A key factor adversely affecting contractor social networking performance is the improper handling and information management of contractor’s services delivery on websites…

1892

Abstract

Purpose

A key factor adversely affecting contractor social networking performance is the improper handling and information management of contractor’s services delivery on websites. Contractor social networking is particularly problematic on industrialised building system (IBS) infrastructure maintenance projects where contractor’s certified quality product and firms are not matched with maintenance specialisation services. The paper aims to discuss this issue.

Design/methodology/approach

This paper reports on the early stages of research which is developing a new information and communications technology (ICT)-based approach to managing contractor social networking on IBS infrastructure maintenance schemes. As a precursor to this work, the paper reviews current contractor social networking websites practices on IBS infrastructure maintenance projects and explores the ICT tools and techniques currently being employed on such projects.

Findings

The findings reveal the need for more sophisticated contractor social networking websites solutions which accord with the needs of IBS infrastructure maintenance schemes.

Originality/value

The paper concludes by presenting a research framework for developing such a system in the future.

Details

Engineering, Construction and Architectural Management, vol. 25 no. 4
Type: Research Article
ISSN: 0969-9988

Keywords

Open Access
Article
Publication date: 12 March 2019

Mounir Bensalah, Abdelmajid Elouadi and Hassan Mharzi

The authors will give an overview of the railway market, with a focus on Morocco, before seeing the challenges to face, before listing some benefits of rail links in terms of…

9114

Abstract

Purpose

The authors will give an overview of the railway market, with a focus on Morocco, before seeing the challenges to face, before listing some benefits of rail links in terms of development, ecology, security, space management, etc. The authors will then give an overview of the development of BIM, its benefits, risks and issues. The purpose of this paper is to verify that the BIM can provide the railway with the tools to face some of its challenges and improve its productivity.

Design/methodology/approach

This paper is part of our research project on the integration of BIM in railway, which is the result of a partnership between Colas Rail Maroc and the ENSAK of the Ibn Tofail University of Kenitra. The objective of this paper is mainly to confirm that the integration of BIM with the railway, through a theoretical and practical study, can have positive impacts. To do this, our methodology consists in studying briefly the development of the railway, the need to improve the budgets and schedules of the projects, to increase the productivity, before showing the advantages of the BIM in the sector of the Architecture, Engineering and Construction (AEC). The study of feedback from railway projects (chosen for their date of completion – beyond 2014, their size, their geographical situation in several countries and for the availability of literature in a new field) will confirm the initial hypotheses. Among the projects studied will be a project that has been the subject of an article written by the authors of this paper. In the discussion of the results, the authors will focus on the benefits, risks and limitations of integrating BIM into the railway. In conclusion, the authors are laying the groundwork for future research in the field.

Findings

The cases study discussed in this paper and previous research confirms the hypotheses of the literature. The integration of BIM into railway projects can have several advantages: collaboration, time saving, cost optimization, prevention of conflicts between networks, construction before construction, optimization of facility management, improvement of the quality of works, prefabrication. They also allowed us to illustrate the risks (status and appropriation of the BIM model, lack of standardization of versions or software and lack of understanding of the basics of schedules and specifications) and limitations (lack of feedback, lack of adaptability and convergence of tools). These experiences have also shown that the use of BIM is not just a technological transition, but a revolution in the project management process, which requires several key success factors (participation of all, commitment, change management and adoption of the collaborative approach). Visualization, collaboration and conflict elimination are the three main chapters where the benefits of BIM can be organized. In fact, there is a lot of intersection between these chapters, but they have been chosen as the main ideas around which all the benefits can be better understood. Visualization primarily addresses the benefits to an individual and improving one’s personal understanding as a result of using BIM. The collaboration refers to the cooperative action of several team members, which is encouraged and facilitated by BIM. Conflict elimination mainly concerns project-related benefits, such as conflict reduction, waste, risks, costs and time. For railway infrastructure projects, the main purpose of using BIM is to improve the design integration process, internal project team communication and collision detection to eliminate risk of rehabilitation.

Research limitations/implications

The application of the BIM process in railway infrastructure requires constant improvement. This concerns the development of libraries and the models available to all users in order to encourage the development of this methodology and, consequently, its use of information throughout the life cycle of an infrastructure work.

Practical implications

The case study of real projects incorporating BIM confirms the results of the literature review. The benefits of integrating BIM into rail projects are multiple and proven: cost control, decision support, avoids extra work due to design errors, improves detection of interface problems, improves planning of vision, help with prefabrication and facility management, etc. Finally, the BIM process is able to overcome delays in procedures slowing the development of the construction industry in many countries, especially in Morocco, because of the slowness of design (or downright bad design).

Social implications

The integration of BIM into rail is becoming a global trend. This integration requires government decisions and a maturation of technology and tools. The authorities of some developed countries studied (Sweden, UK, France, Germany) in the railways, at different stages of implementation, are adopting BIM in the process of setting up new railway projects. This political impulse is still behind in southern countries, such as Morocco. The trend and the data collected indicate an adoption between 2020 and 2030 of BIM in all/some AEC projects in developed countries. This will have an impact on other countries that will soon be doing the same, especially in the railway sector to adopt the BIM.

Originality/value

As part of the realization of this paper, we proceeded to the implementation of an electrical substation as part of the project to build 40 electric traction substations built by Colas Rail on behalf of ONCF.

Details

Smart and Sustainable Built Environment, vol. 8 no. 2
Type: Research Article
ISSN: 2046-6099

Keywords

Open Access
Article
Publication date: 22 June 2020

Andrei Alexander Lux, Flávio Romero Macau and Kerry Ann Brown

This paper extends entrepreneurial ecosystems theory by testing how aspects of the local business environment affect individual entrepreneurs' ability to translate their personal…

4942

Abstract

Purpose

This paper extends entrepreneurial ecosystems theory by testing how aspects of the local business environment affect individual entrepreneurs' ability to translate their personal resources into firm performance.

Design/methodology/approach

Data were collected from 223 business owners across Australia. Moderation hypotheses were tested using multiple hierarchical regression and confirmed with the Preacher and Hayes (2004) bootstrapping method.

Findings

The results show that business owners' psychological capital, social capital and entrepreneurial education directly affect their individual firm performance. These positive relations are moderated by specific aspects of the business environment, such that they are stronger when the environment is more favorable.

Originality/value

This study puts individual business owners back into entrepreneurial ecosystems theory and explains how they can make the most of their personal resources, suggesting a complex interplay where one size does not fit all. Far-reaching practical implications for policymakers are discussed.

Details

International Journal of Entrepreneurial Behavior & Research, vol. 26 no. 5
Type: Research Article
ISSN: 1355-2554

Keywords

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