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421.
顾伟杰 《城市道桥与防洪》2011,(8):288-289,307,7
该文介绍了地铁车站施工对运营中地铁车站保护的施工措施,并通过工程实例,阐述了该工艺的施工方法及所取得的成果。  相似文献   
422.
针对中国城市化进程不断加速的趋势,面向十二五期间中国城市群发展对交通发展的影响和要求,运用系统分析、交通规划、城市规划、需求分析以及适应性的理论和方法,从城市群交通需求特征、网络结构以及交通模式3个方面全面分析中国城市群交通系统发展特征,提出了适应中国城市群交通发展的总体思路和发展对策。研究结果表明:中国城市群交通系统仍需不断完善,应重点关注城市群城际通道优化、城市出入口衔接、综合枢纽建设以及一体化管理体制的推进。研究结果能够为科学制定中国城市群交通发展规划及相关政策奠定基础。  相似文献   
423.
吕军 《中南公路工程》2011,(3):149-151,156
以上瑞高速公路怀新段第8合同段青山冲隧道为工程实例,针对左线出口端洞口浅埋偏压情况,为了节约工程投资,实施了反压回填的处治方案,采用数值模拟分析及现场监控量测数据分析了偏压隧道支护结构的受力状态和稳定性,可供类似工程参考。  相似文献   
424.
随着城市交通拥堵问题的日益突出,在物流需求质量要求越来越高的背景下,物流配送的准时性成为物流业发展的一个十分重要的问题。在道路网络畅通可靠度理论的基础上,进行基于畅通可靠度的城市物流配送运输网络优化研究。提出了物流配送运输网络畅通可靠度的概念,建立了物流配送运输网络优化模型,给出了蚁群算法的求解过程,最后进行了案例比较分析,验证了所建模型的实用性。提出的物流配送网络优化模型对指导城市物流配送运输网络优化决策,降低城市物流配送过程中的不确定性具有较好的实用意义。  相似文献   
425.
为解决穿村镇公路由于警告标志设置不当而造成的交通安全问题,以北京琉辛路密云县不老屯路段为例,根据驾驶员离散驾驶行为理论和心生理特性,研究穿村镇公路警告标志的前置距离,获得在限速60 km/h的穿村镇公路上,预告需要采取停车措施通过危险地点的警告标志的前置距离应在70~90 m之间的结论,并利用模拟驾驶实验测得驾驶员的心生理数据加以验证。认为细化警告标志的设置位置可以更加有效地指导驾驶员的驾驶,避免因为信息遗漏和误导造成的驾驶误操作,为穿村镇公路交通安全提供了有力保障。  相似文献   
426.
Kåre Rumar 《Transportation》1990,17(3):215-229
Initially the driver's role as a link in the driver-vehicle-road-traffic control-chain is discussed in a historical perspective. The gradual changes and the advantages and problems arising from these changes are discussed from behavioural point of view.Then the driver tasks are analyzed. A separation is made between trip planning, navigation, road following, traffic interaction, rule compliance, other than traffic tasks, car handling and speed choice. The relations between and the weights of these subtasks are discussed. Some existing driver behaviour models are reviewed in relation to the above mentioned tasks.Finally an effort is made based on the analyses of driver tasks and driver models to specify some general and some more specific potential advantages and problems with expected future RTI-systems.  相似文献   
427.
This article deals with highly motorized large West German cities of about 200,000 inhabitants and more, which usually provide reasonable public transport systems. Illegal parking with shares of about 40 to 50% of the total parking is widespread in the parking problem areas of those cities, especially in the inner-city residential and mixed-use areas. Parking spaces are demanded by residents, employees, customers and visitors, and by delivery and service traffic. The different characteristics of parking demands by different user groups are discussed. The total parking supply consists of public and private spaces. The share of private spaces is about 40 to 50% of the total parking spaces in German cities. The amount of car traffic generated by a parking space depends on parking duration and parking turnover, as well as on search traffic. So the change of a space from long-duration use of an employee to short-duration of customers — as often discussed in parking concepts — generates at least five-fold car traffic. The measurements and effects of parking control of public spaces as well as the parking regulations in zoning ordinances, restrictions on the construction of new private parking spaces and park-and-ride are discussed. Finally, a parking concept methodology — using the example of Frankfurt am Main — is discussed.  相似文献   
428.
Reform of trucking Vehicle Weights and Dimensions (VWD) regulations in Canada is now underway. The effect these reforms will have on the freight transportation industry are only recently the subject of research. This paper is part of this new research effort, aimed at understanding how regulatory reform in the trucking sector will affect the existing competitive relationship between trucks and the railways. The paper presents the results of study and research into modelling the relationship between mode choice and the service characteristics that are affected by VWD reform.Using several periods of data, a series of econometric models are developed which help to elucidate the relative relationships between the mode service characteristics for both of the principal interprovincial freight modes. A technique is developed and presented to model railway user costs in order to overcome the complex and often unrepresentable pricing activities of Canadian railways.The strength of the developed econometric models is presented, including their significance and statistical reliability. This is further reinforced by the similarities exhibited by all the models in the series. The selected model is applied to predict market service responses required of the railway industry in order to compete with the trucking sector now adapting to the new regulations.The impact of the newly implemented vehicle weight and dimension reform on the rail transportation industry is analyzed and railway industry improvements aimed at maintaining its market share are presented. The results predicted by the model show that railway user cost reductions should be moderate, and likely less than the level of inflation over the period of time when trucking converts its fleet to take advantage of the new regulations.Abbreviations AASHTO American Association of State Highway and Transportation Officials - CCMTA Canadian Conference of Motor Transport Administrators - EPI End products, inedible commodity classification - GVW Gross Vehicle Weight - NA 1988 VWD National Agreement - RTAC Roads and Transportation Association of Canada - VWD Vehicle Weight(s) and Dimension(s) - WA 1988 VWD Western Agreement  相似文献   
429.
Major highway reconstruction can cause significant disruptions to existing travel patterns and economic activity. Reducing these impacts on travelers, shippers, businesses and residents requires that innovative and effective transportation management actions be developed and implemented. This paper reports the major findings and recommendations of a research study on managing transportation during highway, reconstruction. The primary objectives of the study were
–  to investigate and document the critical interrelationships among state-of-the-art reconstruction and scheduling techniques, traffic accommodation strategies, construction quality control measures, and project planning and evaluation processes, and
–  to formulate and recommend a corridor transportation management process that can be used to develop, implement and evaluate a transportation management plan of strategies to mitigate the corridor-wide impacts of major highway reconstruction.
The recommended process consists of five chronological phases, each composed of many tasks having related focuses within the overall process. Each task is designed to contribute to the common objective of seeing that an effective transportation management plan for mitigating travel impacts throughout the project corridor is successfully realized. This process was formulated on the basis of information collected on 25 highway reconstruction projects throughout the United States by way of site visits, direct meetings with project personnel, requests for documentation, and phone interviews.  相似文献   
430.
随着我国高铁迅速发展,高铁建设如何与城市功能空间协同发展的问题引起广泛关注。为了评价高铁与城市协同发展的效率,本文从城市协同性、高铁枢纽建设、站城距离等角度,构建高铁枢纽建设与城市功能空间协同发展效率评价指标体系。并引入DEA模型进行分析计算其效率匹配度,为城市既有高铁站与城市协同发展程度提供依据。最后以京沪高铁为案例分析了24个车站与所在城市的协同关系效率值,结果表明,北京南站、上海虹桥站等高铁枢纽发展较好,常州北站、苏州北站、天津南站等较差,尤其是天津南站的通过能力、客流量等产出指标还需要进一步加强。  相似文献   
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