城市立交桥施工事故统计与分析

文章基于以往桥梁倒塌事故的分析缺乏针对性,提出了以城市立交桥为分析对象,对1988-2016年间国内发生的多起桥梁倒塌事故进行统计分析,结果表明:事故自2000年左右发生得越来越频繁,主要集中在施工建设阶段,且事发时间主要集中在年中和年末;事故的类型主要分为支架失稳、脚手架失稳、墩柱失稳、钢箱梁倾侧、挂篮事故和贝雷梁事故等六类,其中以支架失稳发生得最为频繁,钢箱梁倾覆造成的平均人员死亡人数最多。     

我国公路桥梁安全状况及对策

文章针对目前我国桥梁安全现状,分析桥梁事故发生的原因,指出解决桥梁安全问题是一个系统工程,须由政府部门和建设、养护、使用单位共同努力才能奏效。     

我国隧道桥梁危险货物运输管理的设想

道路隧道、桥梁是危险货物运输易发生事故的关键节点,容易造成重大损失,应是运输安全的关键风险控制点。本文通过对比分析美国、欧盟的风险管理模式和方法,提出我国在道路隧道、桥梁地段危险货物运输风险管理的建议。     

桥梁钻孔灌注桩施工控制探讨

施工过程控制直接关系到桥梁钻孔灌注桩的质量。众多因素都会对施工过程控制产生影响,甚至导致事故的发生,因此应当加强对桥梁钻孔灌注桩施工过程的控制管理。针对钻孔施工中可能出现的问题,分析桥梁钻孔灌注桩的施工工序,提出相应的解决措施,以供参考。     

生命大过天——广西壮族自治区公路管理局交通基础设施安全隐患排查治理专项行动纪实

2007年6至8月,国内外连续发生3起桥梁坍塌事故,造成重大人员伤亡和财产损失。桥梁安全问题引起了党中央、国务院领导的高度重视。2007年8月17日,交通部召开全国交通系统电视电话会议,李盛霖部长做了题为《认真贯彻落实中央领导同志重要批示精神,深入开展以桥梁为重点的交通基础     

桥梁抗震性能评估及加固方法研究

桥梁由于受到结构以及基础尺寸的影响,很容易发生地震破坏。桥梁结构一旦出现地震破坏,不仅会造成交通运输的中断,同时也有可能造成严重的人员伤亡以及财产损失事故。因此,桥梁抗震设计非常重要,以桥梁工程中最为常见的混凝土桥梁为例,首先分析了现行相关规范中对于桥梁抗震设计的相关要求,进而系统地论述了桥梁抗震性能的评估方法,并提出了提高桥梁抗震性能加固措施,可以为桥梁工程检测与加固工作的实施提供合理的参考。     

重庆桥梁交通安全状况调查与改善技术研究

频繁发生的客车坠桥事故造成了重大的人员伤亡和财产损失,提高桥梁运营安全水平工作十分迫切。文章在对重庆市桥梁交通安全状况调查的基础上,分析了桥梁路段在设计、管理、交通运行等方面存在的问题,提出从桥头视距、道路养护、警示设施设置、中央分隔带设置等方面进行综合整治的安全改善措施,为桥梁的安全设计与管理提供参考。     

高原寒区长大桩基施工技术浅析

大跨径桥梁一般具有上部荷载大及基础埋深大的特点,因此多采用桩基础。然而近年来,由于部分施工单位对桩基础施工中的一些施工要点及质量控制不到位等原因,导致施工事故的发生。本文通过介绍施工技术要点、质量控制关键点等桩基础施工中的各个技术环节,对桩基施工最为广泛的钻孔灌注桩施工技术进行系统的归纳,从而积累桩基础施工经验,确保桩基础承载力满足设计要求。对保证大跨径桥梁桩基础施工安全,避免事故的发生具有重要的理论与现实意义。     

高原寒区长大桩基施工技术浅析

大跨径桥梁具有上部荷载大及基础埋深大的特点,多采用桩基础。近年来,因对桩基础施工中的一些技术要点把握不足以及质量控制不到位等原因,致使施工事故频繁发生。本文通过介绍桩基础施工关键技术环节,如其施工技术要点和质量把控关键点等,特别针对桩基施工最为广泛的钻孔灌注桩施工技术进行系统的归纳,从而积累桩基础施工经验,明确质量控制要点,确保桩基础承载力满足设计要求。对保证大跨径桥梁桩基础施工安全,避免事故的发生具有重要的理论与现实意义。     

搭建平安桥梁

著作者:刘玉民陈惟珍杨修志出版社:人民交通出版社出版时间:2013年2月页数:321页开本:787×1092 1/16价格:55.00元一句话点评:从桥梁养护管理和养护工人文化、技术状况的实际出发,注重实用性、知识性,叙述深入浅出,涉猎内容全面。公路桥梁,安全至上。桥梁养护管理"防之当如渡海浮囊,勿容一针之罅漏",防范错误就像是浮囊渡海,不能容忍哪怕是针孔一样大小的漏洞。近年来,世界各国相继发生的在役桥梁和在建桥梁的垮塌事故,不仅让人们心存担忧,而且还引起了各国政府及世界桥梁工程界的高度关注。社会经济的快速发展,需要桥梁承载着更大的交通量和承载量。桥梁运营时,由于频繁承载,甚至超载,再加上自然灾害,以及交通事故等人为事故的侵袭,会造成桥梁损伤和局部破坏。     

Survey of R&D in PRT systems

A survey of research and development in advanced transit has been made by Chalmers University of Technology in Gothenburg in cooperation with Trans21 in Boston. Summary findings are reported for fourteen academic research programs and ten development programs for PRT. An earlier version of this paper was presented at the International Conference of PRT and other Emerging Systems held in Minneapolis in 1996.     

The Impact of Container Type Diversification on Regional British Port Development Strategies

Abstract

Despite a concentration of container traffic in the southeast of the UK over the last few decades, regional ports are attempting new development strategies to capture or retain specific traffic segments. These include intra-European short-sea traffic and a potentially increasing feeder market. These trends are reflected in the movement of different container types, which result in a number of planning challenges related to changing infrastructural and operational requirements. This paper uses highly disaggregated data on container type movements to address three issues that can inform these planning challenges. First, the imbalance of trade resulting in empty container repositioning; second, the requirement for gauge-cleared rail routes to cater for the increasing proportion of high-cube containers; and third, the specialisation of European short-sea traffic at secondary UK ports. The results reveal the disproportionate repositioning of empty containers at Scottish ports and the importance of 45?ft, high-cube and pallet-wide containers at regional ports, highlighting their focus on intra-European short-sea traffic and raising difficulties relating to their lower quality of landside infrastructure (particularly rail) in comparison to the large south-eastern ports. The potential repercussions on hinterland infrastructure development raise questions about both public and private sector responses to regional port development.     

Modular route bus design – A method of meeting transport operation and vehicle manufacturing requirements

This research examines the problem of route bus specification and vehicle manufacturability. In order for bus operators to provide transport services, a range of vehicle configurations must be available from bus manufacturers, generating variety which has a negative impact on the manufacturing process. Larger part inventories, uncontrolled labour tasks and more troublesome maintenance are known impacts of this variety. This research identifies the functional necessities in route bus interior design and reduces the problems in bus manufacture and operation caused by specification diversity by proposing a modularised system of bus design. In particular, it makes recommendations as to how bus configuration should be carried out, ensuring an optimum mix of operational and manufacturing needs:

• 1.Determine user needs before the bus specification process.
• 2.Designs to be developed by the manufacturer in response to user needs.
• 3.This design should be standardised where possible, as suggested by the user needs.
• 4.Where user needs dictate product variations, apply a mass customisation approach to accommodate these needs.

The recommendations are communicated in design proposals for a modular bus interior, demonstrated by four cases designed to meet the present status quo of bus interior design and predictions for the future of the field.     

Optimization of bus stop locations for improving transit accessibility

A mathematical model is developed in this paper to improve the accessibility of a bus service. To formulate the optimization model, a segment of a bus route is given, on which a number of demand entry points are distributed realistically. The objective total cost function (i.e. the sum of supplier and user costs) is minimized by optimizing the number and locations of stops, subject to non‐additive users' value of time. A numerical example is designed to demonstrate the effectiveness of the method thus developed to optimize the bus stop location problem. The sensitivity of the total cost to various parameters (e.g. value of users' time, access speed, and demand density) and the effect of the parameters on the optimal stop locations are analyzed and discussed.     

Productive efficiency and ownership of urban bus services

The established ownership mix of urban bus operations in Australia provides a unique opportunity to investigate the productivity differences between public and private bus service supply. Using duality theory in economics which links economic indices of factor productivity to the cost structure of a firm, we develop empirical measures of total and partial productivity of inputs, and adjust the differences for the effects of ownership status and operating environment. The evidence supports the notion that private supply of public passenger transport in general has performed more efficiently in the past than public supply, although the differences in productivity need not continue in the future.     

管道风险分析指数评分法中分值调整初探

管道风险分析指数评分法中重要步骤之一就是确定影响管道事故因素的权重,各个管道风险因素在整个管道事故中所占的权重是不相同的。针对目前管道风险分析指数评分法基本假设之一（各因素的分值范围都是0～100分）,为了更加客观、准确、合理地反映各个风险因素对于管道事故的影响程度,提出并论述了依据层次分析法的数学逻辑性进行综合计算得出管道风险因素的权重,然后对评分法中各个因素的最高分值,根据其权重不同进行相应调整,从而增强评价者对风险因素的认识和评判能力,提高管道风险评价结果的准确性。     

Determinants of modal choice in freight transport

In the next few years, exciting developments in the field of freight transport are likely to occur. The Channel Tunnel will be perceived as giving railways much greater distance of operation, compared to the current train ferry to/from Great Britain. The further development of swap-body technology will allow easier modal transfer and the creation, in 1992, of a single market in Europe will transform the pattern of trade. All of these are likely to have significant impacts on modal choice, and hence modal split, in freight transport. Reappraisal by many firms of the modes of transport used is likely but will it result in a net transfer of freight from road to rail and, if so, to what extent? To answer such questions, an accurate and reliable method of predicting modal split is required. Research in the past has concentrated on the development of modal split models based on generalised costs. These fail to explain adequately the prevalence of road freight in the UK. From surveys of freight managers within industry, it is clear that models to date rely too heavily on the economic cost factor and too little on behavioural factors (Jeffs 1985). This paper derives from a recent study of freight transport modal choice from the standpoint of the transport decision-maker within the firm. It attempts to shed light on the actual parameters which should be incorporated into a modal split model. Many variables appear to exert an influence on modal choice decision-making process. However, it is possible to categorise them into six main groups, namely: customer-requirements; product-characteristics; company structure/organisation; government interventions; available transport facilities; and perceptions of the decision-maker him/herself. It is the interactions and inter-relationships between these which ultimately determine freight modal split. This study has shown that the relationship between the outcome of the transport decision process and the values of particular determinants of modal split is not straight-forward, due to the complexity and variety of interactions involved. Perhaps one of the main reasons for researchers' failure hitherto to develop a successful modal-split model has been the preoccupation with techniques that rely on the development of common metric (e.g. generalised cost), which has led to the exclusion of some important explanatory variables along quite different dimensions. Another important issue concerns the appropriate level of aggregation. In order not to reduce the explanatory power of the key variables, it is important to work at a disaggregate level, although this does make substantial demands on data. The use of factor analysis enables both the aggregation of information without loss of behavioural reality and the specification of variables in terms of a common metric. In conclusion, freight transport has usually been examined within too narrow a framework. It must be placed firmly within the context of the total industrial process. The demand for freight transport is directly influenced by the level, composition and geographical distribution of production and consumption activities. Freight flows are complex and so it is highly unlikely that a universal mode-choice model can ever be developed. Future research should, therefore, be directed towards developing partial models in response to specific needs of those involved in decision-taking in the freight sector.     

A century of evolution of the accessibility concept

The concept of accessibility has acquired numerous meanings along multiple dimensions during the century of its evolution. This essay argues for the salience of two dimensions: application-based and definition-based. In its application, accessibility has incorporated positive and normative dimensions which have varied in prominence over time. In its definition, accessibility has varied between a mode of evaluation incorporating measured mobility and proximity, on the one hand, and a predefined market basket of urbanist improvements to transportation and land use systems, on the other. Advocates of the accessibility shift should emphasize both the measured approach to accessibility and accessibility’s normative side.