柔性基层在路面病害治理中的应用

通过对半刚性基层和柔性基层特点进行对比分析,叙述了柔性基层材料在半刚性基层沥青路面裂缝治理中的可行性。     

长寿命路面设计与应用探讨

针对目前国内半刚性基层沥青路面普遍出现的早损现象,吸收国外先进的设计理念,合理考虑超载影响,结合高速公路路面维修实例,对柔性路面基层进行了有益的探讨,寻找适宜的路面结构,延长沥青路面全寿命面使用周期.     

冷再生半刚性道路基层修筑技术

针对我国沥青路面结构的特点,依托实体工程开展就地冷再生半刚性基层配合比设计及施工工艺研究。     

大碎石沥青混合料柔性基层在路面补强中的应用

在旧路的改造工程中采用大碎石沥青混合料柔性基层能够充分满足结构强度和高温稳定性要求,同时可起到路面结构排水的作用,并且在一定程度上可以有效地防止反射裂缝的出现。文章结合具体的旧路改造工程实例,介绍大碎石沥青混合料柔性基层施工工艺及质量控制与检验方法,以期对类似工程起到借鉴作用。     

广佛高速公路沥青路面破坏分析与结构优化

以广佛高速公路路面状况调查和评价为背景,介绍了半刚性基层沥青路面结构破坏机理,对半刚性基层沥青路面的破坏原因进行了分析.引入永久性路面结构概念,提出了沥青路面结构优化方向.     

基于沥青路面半刚性结构的破损研究及评价

半刚性基层路面的性能评价是对路面养护、铺装、维护的有力依据。然而依据现行公路技术评价体系对西部高速公路进行评价时,路面状况指数经常超限。针对这一问题,文章基于国内外沥青路面破损及评价研究现状,从计算弯沉值、路面结构强度指数PSSI、路面车辙状况RDI等方面,研究了半刚性基层沥青路面结构破损状况的计算方法,并结合工程实例进行了应用分析,为沥青路面半刚性结构破损评价提供理论依据。     

公路工程施工中的沥青路面冷再生技术

在公路工程施工中,沥青路面冷再生技术有重要作用,为提高该技术应用效果,结合工程实例对公路工程沥青路面冷再生技术的应用进行研究。分析了测量放样、旧路面预处理、原材料选择、撒布水泥与乳化沥青、再生路面整形、碾压与养护等沥青路面冷再生技术应用要点。根据检验结果可知,通过合理控制上述要点,该项目的再生基层多项指标满足设计要求,沥青路面结构更加稳固,可保障车辆通行安全,可为同类工程提供参考。     

半刚性基层沥青路面结构优化设计

文章在对沥青路面早期损坏原因进行分析的基础上，探讨了解决路面早期损坏的途径，提出了采用组合式基层的优化设计思路，并对组合式基层沥青路面结构进行了设计分析，认为组合式基层沥青路面是一种比较适合于重载交通的路面结构。     

混合式基层沥青路面结构的力学特性研究

文章拟定3种混合式基层沥青路面结构,通过BISAR软件进行路面应力、应变计算分析,研究不同混合式基层路面结构的力学性能。研究结果对混合式基层沥青路面的设计、施工及养护具有一定的指导意义。     

浅析水稳基层施工工艺对沥青路面裂缝产生的影响

路面结构是一个整体,它依附在土基之上,由沥青面层、基层、底基层、垫层等部分组成,任何一个结构层次存在缺陷或者各层间衔接不当都有可能导致路面出现裂缝。本文以某高等级公路沥青路面水稳基层为例,就其施工工艺对沥青路面裂缝产生的影响从原材料控制、施工过程控制、施工后的养生、底基层或垫层的处理四个方面分析了如何有效减少沥青路面出现的各种裂缝数量,减缓裂缝出现的时间,达到延长沥青路面使用寿命的目的。     

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.     

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.     

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.     

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.     

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。     

天然气站往复式压缩机活塞失效分析

针对天然气站往复式压缩机活塞的断裂事故,运用失效分析方法,开展了活塞断口扫描电镜分析、能谱和金相分析。根据断口形貌的电镜和金相观察结果,结合理论知识,分析确定了该活塞发生断裂事故的主要原因,即在特定工况下该活塞的材料缺陷是造成断裂的主要因素。     

中国城市道路规划方位性问题研究

文章结合中国的传统建筑文化理念和现代科学原理,从历史文化、能源节约、环境保护、房地产定价、交通安全等多方面分析研究了城市道路在规划和设计时所应遵从的定向规则。     

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.     

生命大过天

文章介绍了广西壮族自治区公路管理局开展专项行动,治理以桥梁为重点的交通基础设施安全隐患的情况,针对在役桥梁、在建桥梁和农村公路桥梁存在的安全隐患提出了相应的治理措施。