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1.
In the course of Deutsche Bahn's new high - speed railway line between Nuremberg and Ingolstadt, a number of tunnels are being constructed, with a total length of about 15 km. One of the longest tunnel is the 7,250 m long Irlahüll tunnel.The tunnel was driven in karst geology. It was not expected that karst phenomena would be so widespread. This forced client, designer and contractor to take a new approach to the project. Different tools were developed to handle the problems on site. Additional site investigations had to be performed to identify karst phenomena in the vicinity of the tunnel. For validating the stability and serviceability of the tunnel, a new way of defining the probability of failure of the construction had to be found. Based on the experience of the tunnel driving at the high - speed railway line in Germany between Nuremberg and Ingolstadt, two different methods of tunnelling are discussed: Drill and blast ( New Austrian Tunnelling Method: NATM) and the use of tunnel boring machines (TBM).  相似文献   

2.
Kane  Lisa  Del Mistro  Romano 《Transportation》2003,30(2):113-131
The 1990s saw the emergence of influential transport legislation both in the UK and in the USA. This "watershed" period appears to indicate that a significant turning point in transport policy is underway. There is now a need to re-evaluate how transport planning is done, and to consider changes to commonly used methods. Criticisms of urban transport planning are traced in the paper. These often focus on the four-stage modelling approach, but some authors also criticise the "rational comprehensive" paradigmatical framework within which the use of four-stage computer models is situated. It is argued that the rational comprehensive model of thinking is less useful today, due to the increasing complexity of the transport planning exercise; the rejection by the public of the transport planner as "expert"; and the highly political nature of transport planning. Alternative approaches are needed in order to address the new types of problems which transport planners face. The use of one such alternative approach, the Soft Systems Methodology, is illustrated as suitable for investigating complex decision-making systems in transport planning. It is suggested that this method could be beneficial in other problematic transport planning situations where the rational comprehensive approaches prove inadequate. Finally, the paper briefly looks ahead and considers the implications of a changing policy environment to the training of transport planners in the future.  相似文献   

3.
Using four consecutive days of SITRAMP 2004 data from the Jakarta metropolitan area (JMA), Indonesia, this study examines the interactions between individuals’ activity-travel parameters, given the variability in their daily constraints, resources, land use and road network conditions. While there have been a significant number of studies into day-to-day variability in travel behaviour in developed countries, this issue is rarely examined in developing countries. The results show that some activity-travel parameter interactions are similar to those produced by travellers from developed countries, while others differ. Household and individual characteristics are the most significant variables influencing the interactions between activity-travel parameters. Different groups of travellers exhibit different trade-off mechanisms. Further analyses of the stability of activity-travel patterns across different days are also provided. Daily commuting time and regular work and study commitments heavily shape workers’ and students’ flexibility in arranging their travel time and out-of-home time budget, leading to more stable daily activity-travel patterns than non-workers.  相似文献   

4.
Abstract

Railways restructuring takes place under very different circumstances and with very different goals in Western Europe, Central and Eastern Europe, and Russia. There are some improvements in productivity associated with the reforms in the European Union (among others access to infrastructure and vertical separation). But they are not certain to be replicated following similar restructuring in transition economies, especially if one takes account of the much higher shadow price on government subsidies in the latter. The current and proposed reforms in the railways of Central and Eastern Europe and Russia are described in detail; the likely outcomes of reforms in the special economic, regulatory and legal environments of these countries are analysed; and an alternative proposal for restructuring in Russia is presented.  相似文献   

5.
The purpose of this article is to present an optimization model to plan the deployment strategy for hydrogen refuelling stations in a city when Origin–Destination (OD) data are not available. This model considers two objectives: to maximize the traffic covered by the selected hydrogen refuelling stations and minimize the average distance of the city’s inhabitants to the nearest hydrogen refuelling station. As OD data are assumed to be unavailable, the clustering of stations in the highest traffic zones is prevented by a new constraint that takes into account information on the distribution of existing conventional refuelling stations. This model is applied to Seville, a city in Southern Spain of about 140 km2 with a population of around 700,000. This application uses the results of a survey of more than 200 Sevillian drivers on their current refuelling tendencies, their willingness to use alternative fuel vehicles and their minimum requirements (regarding maximum distance to be travelled to refuel and number of stations in the city) when establishing a network of alternative refuelling stations.  相似文献   

6.
7.
Suburban sprawl has been widely criticized for its contribution to auto dependence. Numerous studies have found that residents in suburban neighborhoods drive more and walk less than their counterparts in traditional environments. However, most studies confirm only an association between the built environment and travel behavior, and have yet to establish the predominant underlying causal link: whether neighborhood design independently influences travel behavior or whether preferences for travel options affect residential choice. That is, residential self-selection may be at work. A few studies have recently addressed the influence of self-selection. However, our understanding of the causality issue is still immature. To address this issue, this study took into account individuals’ self-selection by employing a quasi-longitudinal design and by controlling for residential preferences and travel attitudes. In particular, using data collected from 547 movers currently living in four traditional neighborhoods and four suburban neighborhoods in Northern California, we developed a structural equations model to investigate the relationships among changes in the built environment, changes in auto ownership, and changes in travel behavior. The results provide some encouragement that land-use policies designed to put residents closer to destinations and provide them with alternative transportation options will actually lead to less driving and more walking.
Susan L. HandyEmail:

Xinyu (Jason) Cao   is a research fellow in the Upper Great Plains Transportation Institute at North Dakota State University. His research interests include the influences of land use on travel and physical activity, and transportation planning. Patricia L. Mokhtarian   is a professor of Civil and Environmental Engineering, Chair of the interdisciplinary Transportation Technology and Policy graduate program, and Associate Director for Education of the Institute of Transportation Studies at the University of California, Davis. She specializes in the study of travel behavior. Susan L. Handy   is a professor in the Department of Environmental Science and Policy and Director of the Sustainable Transportation Center at the University of California, Davis. Her research interests center around the relationships between transportation and land use, particularly the impact of neighborhood design on travel behavior.  相似文献   

8.
Abstract

The institutional environment of rail transport has changed as a result of recent European directives, but the changes have taken different forms from one country to another. In the case of international maritime chains, the development of door‐to‐door services makes inland haulage from the loading and discharging ports extremely important, and it highlights the need to reshape the rail freight industry. This paper analyses the degree of involvement of different actors drawn from the maritime industry in developing and commercializing rail services in the changing regulatory environment. Several maritime operators, shipping lines, port‐handling companies and port authorities have been involved in some container rail services since the early days of liberalization. Their commitments take very different forms, however. Whereas contracts are mainly used for the provision of service, particularly for train haulage, integration by means of shareholding or creating subsidiaries or joint ventures is used for marketing. Important differences between France, the UK, Germany and the Netherlands are detailed. In the latter two countries, there is more involvement in the provision of rail services. Marketing rail services appear to be the main strategic issue for the maritime operators in all four countries  相似文献   

9.
The CCS Hydropower Station in Ecuador is a water diversion type power station, in which two superdeep vertical shafts with depth of 537.9 m are arranged. After comparison of alternative options, a new type of 1088DC RHINO raise boring machine was chosen to construct the vertical shafts. The construction process with the raise boring machine is divided into 3 stages, i.e. pilot hole construction by forward drilling, pilot shaft construction by reverse expanded excavation and shaft construction by manual expanded excavation. In view of the problems of buried drill bits and pilot hole deflection in the first stage, the problems of shaft collapse and cutter damage in the second stage, and the problems of collapse, water inflow and shaft blocking in the third stage, some preventive and treatment measures were proposed based on causes analysis, and good construction effect was achieved. The success- ful construction of super-deep vertical shafts at CCS hydropower station with raise boring method is significant to improve the construction level of deep shafts of domestic water conservancy and hydropower engineering, and the re- lated research can provide a reference for the similar shaft engineering construction. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

10.
截至2011年9月,中国客车统计信息网的数据显示:1~9月全国50家客车企业累计销售客车169231辆,累计增量11268辆,增幅为7.13%。庞大的销量下,我们很难想象,55年前的中国,甚至连一辆"made inChina"的客车都没有!建国前到建国初期,上海百老汇门口,偶尔能看见几辆略显破旧又摇摇欲坠的大客车缓缓开过,车尾的铜  相似文献   

11.
During the 1950s, the share of freight carried by railroads was similar and declining in both the United States and Europe. By 2000, the railroads’ share of freight (measured in ton–kilometers) had reached 38% in the United States while falling to 8% in Europe. This paper examines the reasons for the difference in rail’s share of freight in Europe and the United States. We find that almost 83% of the gap in 2000 is probably due to natural or inherent differences, principally geography, shipment distance, and commodity mix. However, 17% of the gap cannot be explained by these inherent differences and is presumably due to public policies including priority of passenger service, lack of interoperability at borders, service quality and rates, and incentives of the rail operators. We estimate that if that policy gap were closed, railroads’ share of freight in Europe would increase from 8% to 13%.
Mark FaganEmail:
  相似文献   

12.
Shunting locomotive/switcher (AmE)/utilization profiles are analyzed in this paper, in particular on the basis of idle time data collected in nineteen Polish industrial sidings and yards. 40 years old, diesel-electric locomotives are observed during 1000 h. Idle times related to work cycles are analyzed statistically. The percentage of the shunting locomotive daily operating time that the engine is operating at idle amounts to 70% (from 55% to 90%), and average daily idle fuels consumption amounts to 150 l a day (from 90 to 240 l a day).Many European and Asian countries still operate a significant number of similar (ChME3, e.g. S200) old, diesel-electric locomotives (almost 8000 locomotives have been produced), for moving trains over long distances and as shunting locomotives.Observed frequent short idle time periods suggest necessity of widening future scope of idling times’ analysis. Adaptation of Polish rolling stock will be possible using prior general public education about dangerous carcinogens in diesel exhaust smoke and fuel waste related to diesel engines’ idling. Simple simultaneous depiction of diesel engine power time series together with idle time could be used for educational visualization of idling among a wider audience. In the future classical aggregated idle time statistics should be supplemented by models that are more related to the variability of shunting locomotives diesel generator’s power time series, e.g. distribution of frequent short individual idle time cases.  相似文献   

13.
For the bed rock of the foundation pit of the Bandar Malaysia North Station (BMNS) in Kuala Lumpur,the karst, fissure and cave are very developed, and curtain grouting, spud grouting and compaction grouting were conducted to achieve waterproofing and reinforcement. A Lugeon test and pumping test were carried out to test the grouting performance. The results show that the waterproofing effect of the Bandar Malaysia North Station (BMNS) is significant, meeting the basic requirements for waterproofing. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

14.
Currently, two immersed tunnels are being constructed in Holland as part of a high speed railway link. Designing and building these two tunnels was a challenge due to a combination of factors: Technical specifications with small tolerances, which are never encountered before in Holland, poor soil conditions and a short construction period had to be managed.Some major aspects will be explained in this paper.  相似文献   

15.
C. A. Nash 《Transportation》1984,12(3):243-259
The 1974 Railways Act set British Rail (BR) the rather vague objective of providing a passenger service broadly comparable with that then existing within a given level of support. For the first few years under the Act, BR succeeded in operating within the financial constraints imposed, but only by considerable increases in charges and by negotiating wage settlements which implied declining real wages. From 1978 on, rising labour costs and reduction in traffic led to a rapidly developing crisis in BR's financial position.The position of each section of BR's business is discussed briefly. It is shown that the designation of some sectors as being purely commercial is inappropriate, since this means that benefits to users and to the community at large are ignored in decision-making. Similarly, the direction to maintain social passenger services at a given level means that finance and investment are concentrated unduly on preservation of the existing pattern of service, rather than on providing value for money. In both sectors, the likelihood is that in general fares are too high and services too frequent.At an operational level, the criterion of maximising the (weighted) volume of traffic carried is advocated as a practical way of choosing between alternative fare and service-level packages. More broadly based strategic studies would be needed to decide on the weights to be adopted, the level of finance to be made available, and the overall strategy.  相似文献   

16.
A sensitivity analysis of plausible errors in population, employment, fuel price, and income projections is conducted using the travel demand and emissions models of the Sacramento, CA, USA, region for their transportation plan. The results of the analyses indicate that plausible error ranges for household income and fuel prices are not a significant source of uncertainty with respect to the region's travel demand and emissions projections. However, plausible errors in population and employment projections (within approximately one standard deviation) may result in the region's transportation plan not meeting the conformity test for nitrogens of oxides (NOx) in the year 2005 (i.e., an approximately 16% probability). This outcome is also possible in the year 2015 but less likely (within approximately two standard deviations or a 2.5% probability). Errors in socioeconomic projections are only one of many sources of error in travel demand and emissions models. These results have several policy implications. First, regions like Sacramento that meet their conformity tests by a very small margin should rethink new highway investment and consider contingency transportation plans that incorporate more aggressive emissions reduction policies. Second, regional transportation planning agencies should conduct sensitivity analyses as part of their conformity analysis to make explicit significant uncertainties in the methods and to identify the probability of their transportation plan not conforming. Third, the US Environmental Protection Agency (EPA) should clarify the interpretation of “demonstrate” conformity of transportation plans; that is, specify the level of certainty that it considers a sufficient demonstration of conformity.  相似文献   

17.
There is a drive towards delivering and operating public infrastructure through public–private partnership (PPP) rather than traditional public procurement. The assessment of the value for money achieved by the two alternative approaches rests in the cost of financing and their efficiency in delivery and operation. This paper focuses on the cost of financing, in particular the cost associated with transferring risk from the public to private sphere. If capital markets were efficient and complete, the cost of public (government) and private financing should be the same, with the relative delivery and operational efficiency remaining as the primary determinant of value-for-money. Evidence suggests, however, that the risk transfer to a PPP entails an inefficient risk pricing premium which goes beyond the direct cost of financing. We argue that a high price for PPPs results from large risk transfers, risk treatment within the private sector, and uncertainty around the past and future performance of public–private consortia. The corollary is that the efficiency gains from a PPP must be much higher than commonly expected to deliver a greater value for the money than under a traditional approach.  相似文献   

18.
Traditionally, theory suggests the ageing individual is strongly influenced by the environment and has difficulties in overcoming distance and space. Recently, however, theory has moved to suggest that older people possess greater agency, being more capable of selecting and mastering their environments and spaces according to their needs and preferences. This paper suggests that both opposing theories are correct for differing groups. Observations and surveys of older people (n = 365) in public space examined how far person–environment agency is present in active use of outdoor space, measured by confidence to use and explore space, in three locations (urban shopping centres, suburban residential area and an area of shared space). In all three areas, dominance of the space was associated with being male and having higher levels of reported health, confidence and higher socio-economic status. Only 11% of participants walked at least as fast as the UK department for transport guidance on crossing speeds.  相似文献   

19.
Karel Martens 《Transportation》2012,39(6):1035-1053
This paper seeks to provide a theoretical basis for a distributive approach to transport. Using the theory developed by Michael Walzer in his ??Spheres of Justice?? (1983), I argue that the transport good, defined as accessibility, should be distributed in a so-called separate sphere, i.e. independent from the way in which other key goods, like money or power, are allocated. I subsequently explore what kind of justice principle could guide the distribution of the transport good, once a separate sphere would be established. This preliminary exploration results in the elimination of a number of widely supported distributive principles, and in the tentative identification of a criterion matching the particularities of the transport good. The explorations in the paper are not intended as final answers, but rather seek to open the debate about the need for an explicit distributive transport policy and the distributive principle that should guide such a policy.  相似文献   

20.
This paper examines the current application of transport appraisal in the UK, in particular exploring the partiality of cost–benefit analysis (CBA) within the wider multi-criteria analysis (MCA) process. It argues that applying a quantitative assessment of the varied impacts of complex transport projects can only be partial within the CBA. Analysis can overlook social, human life, environmental and built environment impacts, and projects can be inconsistent with the planning strategy for an area. The application of CBA is critically reviewed using two case studies: the proposed upgrade of the South Fylde railway line and the Heysham-M6 Link Road, both from North West England. A participatory MCA process is suggested to help improve the process of transport appraisal, as part of an improved public debate on transport investment priorities.  相似文献   

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