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1.
计划经济时代火车“一枝独秀”.上世纪90年代以来公路占尽风光.如今的“和谐号”动车抢尽风头——在交通运输神话的不断演绎中.公铁竞争从未停却。  相似文献   

2.
文章结合世界上海拔最高的青藏铁路风火山隧道的施工实践,从工程设计、机械的选型与配套、制氧、供氧系统的研制及应用、冻土、冻岩光爆、保温、控温、防水保温层的铺设、信息化施工和工序网络管理等方面,介绍了冻土隧道施工新技术。  相似文献   

3.
青藏铁路昆仑山隧道冻胀压力计算   总被引:6,自引:4,他引:6  
隧道衬砌的冻害一直都是人们密切关注的问题,但对作用在衬砌上的冻胀压力大小及模式很少有人进行较深入的研究.文章试图以青藏铁路昆仑山隧道为例,分析隧道衬砌冻胀压力的作用规律,旨在为冻土地区隧道的设计及施工提供参考.  相似文献   

4.
十年前大致,今天变成10:1 我国交通投资领域"贫富悬殊"的失衡局面,到了去年创下最高纪录:在2005年全国交通工作会议上,交通部部长张春贤介绍,2004年我国交通基础设施投资突破5000亿元人民币,投资额是2000年的两倍.而在全国铁路工作会议上,铁道部部长刘志军介绍,2004年全国铁路建设完成的投资总额是510亿元.  相似文献   

5.
文章主要介绍了福建省龙(岩)-长(汀)高速公路隘岭隧道下穿赣(州)-龙(岩)铁路古城隧道的施工工艺和施工方法,并简要阐述了对施工中的公路隧道和运营中的铁路隧道所采取的安全监测措施。  相似文献   

6.
2005年,我国国民经济继续保持高位增长,国内生产总值将超过15万亿元.对外开放进一步扩大,预计2005年进出口总额将超过13800亿美元,比2000年的4743亿美元增长1.9倍.作为对外贸易商品运输的大动脉,全国公路总里程超过190万公里,其中高速公路里程超过4万公里.  相似文献   

7.
通过农村公路建设原则,提出了农村公路网建设要重实用、重排水、重防护的设计要点。  相似文献   

8.
Traffic engineering in Germany has a long tradition. The standards for practical application, however, are distributed among a variety of guidelines. These, in many cases, are not up to date. Therefore, in practice, more recent research results are applied by traffic authorities and consultants. To improve this practical application on a more sophisticated background, a manual for traffic quality and capacity on streets and highways is intended to be prepared. A first draft has been worked out by a university institute and is to be published in 1994. This article presents the background for the chapter on highway sections and motorway interchanges for signalized and unsignalized intersections. Pedestrian and public transit facilities are mentioned as well. Special attention is drawn to the most recent research results which are included in the manual. These are delays at intersections under nonstationary conditions, including queue length and distributions (e.g. 95-percentile queue length). For motorways, the lack of a general speed limit in Germany has important impacts on determining measures of effectiveness.  相似文献   

9.
This paper presents an analysis of a market-based policy aimed at encouraging manufacturers to develop more fuel efficient vehicles without affecting the car buyer’s choice of vehicle size. A vehicle’s size is measured by its “footprint”, the product of track width and wheelbase. Traditional market-based policies to promote higher fuel economy, such as higher gasoline taxes or gas guzzler taxes, also induce motorists to purchase smaller vehicles. Whether or not such policies affect overall road safety remains controversial, however. Feebates, a continuous schedule of new vehicle taxes and rebates as a function of vehicle fuel consumption, can also be made a function of vehicle size, thus removing the incentive to buy a smaller vehicle. A feebate system based on a vehicle’s footprint creates the same incentive to adopt technology to improve fuel economy as simple feebate systems while removing any incentive for manufacturers or consumers to downsize vehicles.  相似文献   

10.
Two semi-logarithmic regression models are developed to estimate accident rates and accident costs, respectively, for rural non-interstate highways in the state of Iowa. Data on 21,224 accidents occurring between 1989 and 1991 on 17,767 road segments are used in the analysis. Seven road attributes of these road segments are included as predictor variables. Applying the resulting regression models to a rather typical highway upgrade situation, the present value of the accident cost saving is computed. The sensitivity of the estimated cost saving to values for fatal, personal injury, and property damage only accidents is tested.Because factors other than road characteristics greatly influence accident costs, the models developed in this research explain a limited amount of the variance in these costs among road segments. Results of the analysis indicate that the most important attribute associated with accident costs is average daily traffic per lane, followed by conditions requiring passing restrictions and the sharpness of curves. Varying the values for the three categories of accidents shows that results are far more sensitive to the value of personal injuries than fatalities. The feasibility of using predictive models of accident costs in benefit-cost analyses of highway investments is demonstrated.  相似文献   

11.
Strategies used to deploy technological innovations are central determinants of the degree to which those innovations realize their potential effect on social and economic productivity. The U.S. Interstate highway system was a deployment mechanism for the design innovations of high-speed geometric design and the control of highway access. This strategy was defined by rigid uniform minimum standards of facility design, severely constrained alternatives for configuring the network of facilities, and an inflexible and, in some cases, inappropriate institutional structure for constructing facilities. This strategy compromised the realization of productivity improvements available through the deployment of these innovations. This paper explores the origins of this deployment strategy and generalizes to a discussion of deployment strategies for large engineered systems. It shows that each of the Interstate program's provisions derived from traditions of the agency charged with implementing it and from political expedients embraced to enact the program.  相似文献   

12.
物流过程的全程可见性一直是物流信息技术应用的核心问题.而对于广博、复杂的中国版图,实现公路运输途中的全程跟踪一直是所有物流企业、货主的梦想.  相似文献   

13.
Transport planning is based on traffic forecasts which are subject to great uncertainties. These uncertainties have generally been ignored or, at least, not explicitly included in the planning process. This paper describes the principles behind the estimation of the uncertainty (or range of error) of the forecasts of a traffic model and discusses the means by which this information can be absorbed into the decision-making in transport planning projects. These principles have been applied to the appraisal of a British highway project and throughout the paper reference is made to this project in order to illustrate the results of the practical application of an explicit treatment of uncertainty. It is believed that this approach can and should be developed for application in most areas of transport planning, leading inevitably to an improvement in the quality of the decisions taken.  相似文献   

14.
通过对高速公路边坡水土保持的研究,主要论述边坡水土保持植物防护设计的应用,从高速公路水路流失的特点出发,指出边坡为公路水土流失重灾区。进行植物防护设计不仅能够达到防护效果,还有利于恢复植被,改善生态环境,有效地防止水土流失,并介绍了高速公路边坡水土流失植物防护技术设计原则。最后通过实践分析,对植物防护做出具体设计,为今后同类工程的水土保持措施布局提供参考和借鉴。  相似文献   

15.
当前我国铁路建设不断加快,而铁路工程路基施工技术是铁路工程建设的重点之一。基于此,文章以某地区铁路路基工程施工为依托,对铁路工程路基施工中的地基处理及施工过程中的若干问题进行研究,并且结合该铁路路基施工工程的具体情况给出了相应的实施方案,以期能为其他同类型工程的修建提供参考。  相似文献   

16.
In 1963 the Beeching Report on Britain's railways proposed the closure of a substantial part of the railway network (British Railways Board, 1963). Although many services were withdrawn, disquiet at the Report's failure to analyse the social benefits of rail passenger services eventually led to the application of the technique of cost-benefit analysis to the problem of unremunerative rail services. However, although such studies revealed that the retention of many rural rail services could not be justified on social grounds, these services were not withdrawn. This paper outlines briefly the history of attempts to deal with the question of the optimal size of the rail passenger network. Secondly, it considers the social cost-benefit case for reducing the present size of the network in Britain and the quantifiable benefits from such a reduction. The problem of joint costs is discussed. Finally, it attempts to explain the failure of successive Governments to apply the results of cost-benefit studies in practice, and suggests how the decision-making process might be altered to facilitate a more rational approach towards public transport problems in Britain.  相似文献   

17.
从观今宜鉴古、温故而知新角度来概略梳理回顾我国铁路隧道爆破技术的发展史,其意不仅试图鼓励爆破技术同人为隧道爆破事业前仆后继,更望我国的隧道工程爆破技术以崭新的面貌跨入21世纪.  相似文献   

18.
结合公路桥梁养护管理实际,提出了重点监控桥梁养护管理理念,探讨了监控管理原则、监控程序以及实施要求,进一步加强桥梁养护管理,提升管理水平,保障桥梁运营安全。  相似文献   

19.
高速公路监控技术为高速公路的信息化建设提供了很好的手段,对高速公路交通监控系统的内涵、功能和体系结构设计等进行了初步探讨。  相似文献   

20.
结合工程实例介绍了公路隧道施工监测的主要内容及其作用,并对施工监测中存在的一些问题进行了探讨,对提高公路隧道施工监控量测的质量具有一定的指导作用。  相似文献   

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