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1.
随着经济的快速发展,高速公路通车里程得到快速增长,道路客、货运量及周转量不断高速发展,但高速公路的交通安全问题已经成为一个重要的研究课题。本文首先分析了浙江省高速公路交通事故的特点,然后运用轨迹交叉论进行交通事故的原因分析,识别浙江省高速公路危险源,最后有针对性地提出了浙江省高速公路交通事故防治措施。  相似文献   

2.
在深入分析农村公路交通现状的基础上,结合社会主义新农村的建设,研究了社会主义新农村在公路等级及里程、客运及货物运输系统、公路养护与管理、道路交通安全防护等方面对交通的需求,提出了适应社会主义新农村建设的道路交通安全保障措施。  相似文献   

3.
The forecasting of road freight traffic has relied heavily on the close correlation between GDP and road tonne-kilometers. It has not been rooted in an understanding of the causes of freight traffic growth. The research reported in this paper has investigated this process of traffic growth in two ways: first, by analysing official data on the production, consumption and movement of food and drink products, and second, by conducting a survey of the changing freight transport requirements of 88 large British-based manufacturers.The analysis of secondary data shows how, in the food and drink sector, the relationship between the real value of output and road vehicle-kms hinges on four key parameters: value density, handling factor, average length of haul and consignment size. An attempt is made to explain variations in these parameters.The survey of manufacturers suggests that the growth of lorry traffic is the net result of a complex interaction between factors operating at four levels of logistical management: strategic planning of logistical systems, choice of suppliers and distributors, scheduling of product flow and the management of transport resources. Changes in the frequency and scheduling of freight deliveries in response to tightening customer service requirements and just-in-time management appear to have become a more prevalent cause of freight traffic growth than the physical restructuring of logistical systems. Manufacturers anticipate that their road freight demand will broadly increase in line with sales and be largely unaffected by road transport cost increases at the levels currently proposed. The paper concludes by examining their likely reactions to a much sharper increase in the cost of road freight movement.  相似文献   

4.
Jeremy Drew 《运输评论》2013,33(2):223-237
Abstract

This paper reviews and analyses the benefits for rail freight customers of the two principal models for introducing competition in main line railway networks: (1) the vertical separation of infrastructure from operations; and (2) the introduction of competition providing other operators with open access to the network. The paper shows that traffic growth has generally been higher in those European countries that have liberalized most. It then examines in detail the impact of restructuring in Great Britain in terms of the competition, freight rates and traffic growth. The paper concludes that vertical separation benefits freight customers more than just open access.  相似文献   

5.
Highway work zones caused excessive delay to road users. To reduce user and maintenance costs, work zones shall be designed and scheduled accordingly. An analytical model is developed to jointly optimize work zone lengths and schedule as well as diverted traffic volume for highway maintenance projects, considering time‐varying demand, variable maintenance cost, and various production rates of maintenance crew. With a genetic algorithm, an iterative procedure is developed to search for the optimal solution. A numerical example is illustrated, in which various traffic mitigation plans for a highway maintenance project are evaluated. A sensitivity analysis is conducted, and results indicate the threshold volumes for various conditions (e.g., maintenance crews and capacity of the work zone) at which diverting traffic is desirable. This study demonstrates an effective approach to search for the optimal work zone schedule, which is also applicable to evaluate the effectiveness of traffic diversion plans for a pre‐planned work zone schedule. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

6.
High-speed rail is often touted as a means to reduce congestion on the United States’ highways by removing passenger car traffic. But highway congestion can also be reduced by reducing the amount of freight traffic. So, given the advances in high-speed rail, the potential exists for developing a national high-speed network for freight distribution. To design such a network considering highway traffic and transit times, we present an uncapacitated network design model with a post-processing step for the capacity constraint. To illustrate how our modeling approach could be used by policy makers to evaluate the impacts of a high-speed rail network, we apply our models with preliminary data on high-speed rail operating parameters for freight applications and from current data on shipments from a major truckload carrier and the US Census Bureau.  相似文献   

7.
公路隧道交通安全措施探索   总被引:1,自引:0,他引:1  
保障公路隧道的交通安全不仅事关隧道内司乘人员的生命安全,对隧道本身的结构安全同样有很大的影响。从公路隧道的总体设计、交通工程设施、防火、隧道内装、洞口增减光设施、火灾的预防与救援、隧道的运营管理、宣传教育和交通法规等多方面对影响公路隧道交通安全的因素和相关措施进行了探讨,旨在为公路隧道交通安全措施的研究提供一些思路。  相似文献   

8.

In recent years, Chinese railway freight transport has been facing great challenges from transport market reformation and economic expansion. Although the total volume of railway freight has been increasing, its market share has decreased greatly, especially at the beginning of migration from command economy to market economy. This paper considers four aspects believed to be responsible for the loss of the railway freight market share. First, we review the history and current situation of the Chinese railway freight transport and study the relationship between economic development and freight transport in China. Second, the causes resulting in the loss of the market share of railway freight are analysed in detail. Third, the current measures taken by Chinese Railways (CR) to restore its competitiveness are discussed. The effects of these measures on railway traffic volume, market share and productivity are also studied. Finally, the way forward for the future of CR is discussed. It is concluded that CR has not yet adapted sufficiently to new economic conditions, although in recent years progress has been made. Further reform will be needed.  相似文献   

9.
Intermodal rail/road freight transport has always been considered as a competitive alternative to its road freight counterpart in the European medium- to long-distance corridors (markets). Such consideration has been based on the increasing competitiveness of some innovative rail services and the existing and prospective performance of both modes in terms of the full social – internal or operational and external – costs. The most recent innovation of rail technologies and related services launched by some European railway companies, still at the conceptual level, is the Long Intermodal Freight Train (LIFT). This is supposed to be a block train operating in long-distance corridors (markets) with a substantial and regular freight demand.This paper develops analytical models for assessing the performance of the LIFTs, the already-operating Conventional Intermodal Freight Trains (CIFTs), and their road counterpart as well. The performance consists of the full – internal (private) and external – costs of the door-to-door delivery of loading units – containers, swap-bodies, and semi-trailers. The internal costs embrace the operational costs of the transport (rail and road) and intermodal terminal operators. The external costs include the costs of the impacts of door-to-door delivery of loading units on society and the environment. These negative externalities include noise, air pollution, traffic accidents, and congestion.The models are applied to a simplified version of intermodal and road transport system using inputs from the European freight transport sector. The aims are to compare the full costs of particular modalities in order to investigate the potential of the LIFTs as compared with the CIFTs in improving the internal efficiency of the rail freight sector and its competitiveness with respect to its road counterpart. In addition, the paper attempts to assess some effects on the potential modal shift of EU (European Union) transport policies on internalizing transport externalities.  相似文献   

10.
Russ Haywood 《运输评论》2013,33(4):387-412

Over the last couple of decades there has been a trend in Western Europe and North America towards making the railway industry more able to compete successfully with road for freight haulage through deregulation and/or structural change. This trend has been drive, partly, by a concern to produce more commercially viable railway industries, but also by concerns to reduce the environmental impacts of road haulage through modal shift. The latter in particular has led to the development of public policies supportive of rail freight, particularly at the national or international levels. This paper reports on qualitative research that analysed public policy aimed at promoting rail freight in Britain but, unusually, the focus was on local rather than national policy. The research was an investigation of the approach of local authorities to the encouragement of rail freight as evidenced through their Local Transport Plans. The paper concludes that in Britain there has been a significant amount of local policymaking for rail freight and that although national policy matters are of overriding importance, the role of local policy is significant and can be developed further.  相似文献   

11.
基于我国道路货物运输的发展现状,以探索推行道路货物运输网络化的发展模式为主线,以提高道路货物运输组织效率和行业发展水平为最终目标,阐述道路货物网络化运输的概念及内涵,对网络化运输服务进行了划分,构建了我国推行道路货物网络化运输的两类发展模式,并利用图示和文字结合的方式对其进行了分析评价。  相似文献   

12.
高速公路的取、弃土场及施工便道如不采取有效措施加以修复,极易引起水土流失等生态破坏,文章通过总结实例研究,探讨了高速公路取、弃土场与施工便道将工程措施和植物措施相结合的生态修复技术与施工方案,对高速公路取、弃土场及施工便道的生态修复具有一定的技术指导作用。  相似文献   

13.
Road Pricing models with maintenance cost   总被引:2,自引:0,他引:2  
Chu  Chih-Peng  Tsai  Jyh-Fa 《Transportation》2004,31(4):457-477
According to the Federal Highway Administration of the United States, maintenance expenditure takes up more than 25% of road revenue disbursement and this percentage has been increasing gradually. The reason for the increment in maintenance cost is that there lacks incentives for road users to take this cost component into their driving behavior. That is, different classes of vehicles should be levied different levels of congestion tax due to the different degrees of damage on the highway if a road pricing policy is implemented. This paper intends to incorporate this concept into road pricing literature by introducing two types of vehicles. After the analysis of the problem, we find that different types of vehicles should be charged different tolls. The toll includes not only the travel delay cost of one's own vehicle and the other types of vehicles, but also the marginal maintenance cost that is dependent on the traffic flow. A set of numerical examples is provided to demonstrate the theoretical analyses. The result shows that both the welfare and cost coverage rate will increase when the road pricing mechanism takes the maintenance cost factor into account.  相似文献   

14.
We access the abundance of Xinjiang ground jay near the Taklimakan Desert Highway in Northwestern China, and also we used alert distance and flight initiation distance to evaluate the effects of the Taklimakan Desert Highway on Xinjiang ground jay responses to human encroachment. The results showed that Xinjiang ground jay were more abundant adjacent to the roadway than further way, and the alert distance and flight initiation distance of the Xinjiang ground jay decreased significantly with increasing road effect. These results indicated that the Taklimakan Desert Highway and its shelter forest attracted more Xinjiang ground jay to live near the road, and also the highway significantly affected the bird’s vigilance behavior.  相似文献   

15.
公路在我国的交通中占有重要的一席之地,对我国的经济贡献巨大。近年来,公路的损毁问题也越来越严重,由于公路的损毁导致的交通事故屡见不鲜。因此本文对公路设计中的缺陷及解决措施进行了探讨,提出了一定可行的解决措施。这些解决措施对公路的设计具有一定的参考价值。  相似文献   

16.
以人为本、尊重自然、适用完善是北欧公路的鲜明特点。本文介绍了北欧公路在总体设计、路线、路基路面、排水、桥遂、交通工程及服务设施、运营管理等方面的具体做法,并结合我国公路的现状提出了一些思路。  相似文献   

17.
文章通过对重庆成渝高速公路某段运行后的车流量及路面性能状况进行调查,分析其路面病害状况及产生的原因,研究其路面衰减的规律,并针对各个阶段的路面性能,制定出适宜的养护方案。  相似文献   

18.

Addressing the issues of traffic safety in rural areas presents a constant challenge. The mix of light and heavy vehicles and the considerable differences in speed among these traffic participants result in high risks and delays for the faster vehicles. Agricultural vehicles (AVs) in particular have such an impact on traffic, especially when using arterial highways. This paper reviews the problems of safety and delays that AVs cause on arterial highways, and the appropriate mitigation. The concept of 'sustainable safety' in The Netherlands focuses on these problems, because of the proposed construction of parallel roads alongside all arterial highways. However, Dutch accident statistics cannot justify the high costs for the construction of parallel roads alongside 7000 km of arterial highways. Delays experienced by fast traffic are another reason for separating AVs from other road users with parallel roads. Alternative measures alongside the arterial highway, such as passing bays, restricting AVs to travelling at off-peak only and improving the conspicuity of the AVs, may be more cost-effective ways of reducing delays and/or improving traffic safety on arterial highways. Another solution may be to eliminate the need for AVs to use the arterial highway by altering their routes. For this purpose, land reallocation projects (as practised in Holland) can provide a useful tool.  相似文献   

19.
In this paper, renewal costs for railway tracks are investigated using survival analysis. The purpose is to derive the effect from increased traffic volumes on rail renewal cycle lengths and to calculate associated marginal costs. A flow sample of censored data containing almost 1300 observations on the Swedish main railway network is used. We specify Weibull regression models, and estimate deterioration elasticities for total tonnage as well as for passenger and freight tonnages separately. Marginal costs are calculated as a change in present values of renewal costs from premature renewal following increased traffic volumes. The marginal cost for total tonnage is estimated to approximately SEK 0.002 per gross ton kilometre.  相似文献   

20.
Highway automation entails the application of control, sensing and communication technologies to road vehicles, with the objective of improving highway performance. It has been envisioned that automation could increase highway capacity by a factor of three. The purpose of this paper is to develop a methodology for predicting highway capacity and comparing alternative automation concepts. It extends earlier research on optimal lane assignment on an automated highway to dynamic networks. A path-based linear program is formulated and solved through a column generation method. The algorithm has been applied to networks with as many as 20 on and off ramps, 80 segments, 4 lanes and 12 time periods.  相似文献   

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