武汉三阳路公铁合建长江隧道总体设计关键技术研究

武汉三阳路长江隧道是世界上首座城市道路与地铁合建的盾构隧道,具有超大直径、高水压、小间距、地质条件复杂、建设条件困难等特点,总体设计难度大。文章针对三阳路长江隧道公铁合建的工程实践,结合其工程建设环境条件、隧道施工安全与风险、两种不同交通方式本身的技术要求及在运营防灾救援方面的相互影响等因素,对隧道平面、纵断面、横断面、疏散救援等部分关键技术进行了分析研究,确定了合理的工程总体设计方案,可为类似工程提供参考。     

宁波轨道交通越江隧道盾构法施工控制技术研究

轨道交通越江隧道工程一旦发生事故将造成巨大的社会影响和财产损失。详细分析了宁波越江隧道盾构施工场地的土层及地下障碍物分布情况,对越江隧道盾构在不同地层及软硬分界面处施工、控制河床冲淤对隧道施工的影响、处理管片上浮、结泥饼、穿越河流段浅覆土等关键技术及工程风险进行了分析评价,提出了越江隧道穿堤设计和施工合理化建议,为软土地区轨道交通越江区间隧道盾构施工提供技术参考。     

上海崇明越江通道长江隧道工程综述(一)——长江隧道工程设计

介绍了上海长江隧桥（崇明越江通道）工程的建设背景、规模和上海长江隧道建设的自然条件;阐述了工程总体设计方案,以及超大直径盾构隧道管片结构、大深度高水压管片防水、长距离隧道通风系统和防灾体系等关键技术方案;描述了两台Ф15430泥水加压复合盾构机的性能特点;叙述了隧道总体施工方案和盾构隧道施工正面稳定、大直径隧道抗浮、长距离施工测量、内部结构同步施工、成淡交替土层环境条件下连接通道施工等长大越江隧道关键施工技术方案和风险预案措施。     

越江隧道工程大型泥水盾构进出洞施工关键技术

盾构进出洞施工是上海复兴东路越江隧道工程圆形断面隧道施工的重要环节,其技术的成功与否,将直接影响隧道盾构的正常推进.复兴东路越江隧道工程盾构进出洞段施工难点主要是浅覆土中泥水平衡系统的建立和控制,其进出口段地层的冻结加固处理、洞口的止水设计、盾构轴线控制及泥水平衡控制等都是大型泥水盾构进出洞掘进施工的关键技术.     

珠江口海底隧道盾构法施工方案可行性分析

盾构法已经在国内外的地下工程中被广泛运用,特别是国外一些著名的海底盾构隧道,如英吉利海峡隧道、日本东京湾海底公路隧道、荷兰W esterschelde隧道;国内盾构技术也发展迅速,先后建成上海大连路、复兴东路过江盾构隧道,还有在建的上海翔殷路越江公路隧道、上中路隧道和已经开工建设的武汉、南京、上海长江桥隧工程等。这些海底、江底隧道的修建为盾构隧道的发展积累了丰富的经验。文章首先论述了国内外大直径、高水压、长距离推进等盾构施工关键技术,并结合珠江口海底隧道的建设条件与国内外的施工成功实例,对海底隧道盾构法施工方案的可行性进行了初步研究。     

地铁隧道施工过古城墙的地表变形及控制措施

西安地铁二号线区间隧道施工对城墙等国家级文物的影响是隧道安全施工中需要解决的关键问题之一。文章针对该地铁工程介绍了上行线隧道盾构下穿护城河及城墙时的地表变形控制措施和施工变形监测方案,并对监测结果进行分析。分析结果表明,隧道盾构施工中,造成地表沉降是多种因素共同作用的结果;盾构施工过程中,注浆必须同步、足量且补浆及时;随着盾构的推进,需要不断调整土压力以适应地层的变化。隧道已经安全通过城墙,表明所采用的地表沉降控制措施和监测方案是合理可行的。     

武汉三阳路隧道为国内已建最大直径、世界首条公轨合建的盾构法隧道

正武汉三阳路长江隧道全长2 590 m,直径15.2 m,是长江中上游首条超大直径越江隧道,也是国内已建最大直径、世界首条公轨合建的盾构法隧道,采用2台海瑞克直径15.76 m的泥水气平衡盾构机施工。由于武汉市主城区过江通道资源有限,该隧道规划定位为城市道路与轨道交通7号线共用的越江隧道,道路隧道布置在上层,轨     

壁后注浆对大直径盾构隧道劣化的影响

大直径盾构越江隧道的错台、破损和渗漏之间没有直接的联系,但若注浆量较大容易导致压注点附近较大的错台。结合上海延安东路隧道北线修复工程,针对隧道壁后注浆层厚度、错台、破损和渗水情况进行对比分析,找出了相互间的内在关系;提出了隧道施工中需要注意的问题。这对今后同类型隧道施工具有参考价值。     

大直径泥水盾构施工小半径曲线隧道的质量控制措施

上海长江西路越江隧道系采用15.43m泥水气压盾构施工,为避开逸仙路高架桩基和轨交3号线高架桩基,曲线段隧道的最小转弯半径仅为910m。通过对盾构设备的优化、管片的合理拼装、盾构姿态控制等措施,使隧道轴线平面偏差控制在±40mm内,高程偏差控制在±30mm内;施工中未出现管片碎裂现象,其盾尾间隙均匀,从而保护了盾尾钢丝刷,规避了盾尾漏浆等施工风险,积累的经验可供类似工程参考。     

地面超载对大型盾构施工扰动位移的影响

上海军工路越江隧道工程中泥水系统由于地面条件所限,布置于施工隧道上方,紧临防汛墙的盾构隧道施工影响区域内。泥水系统庞大的自重荷载及设备振动荷载造成地面超载,从而对周围土体产生扰动,造成较为复杂的位移,影响施工过程。本文通过对该隧道工程施工过程中地面超载条件下土体扰动位移进行监测,来研究位移变化规律,分析变化原因,预测发展趋势。     

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.     

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。     

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.     

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。     

Predicting queue variability to enable analysis of overload risk

ABSTRACT

Predicting the risk of traffic demands and delays exceeding critical limits at road junctions, airports, hospitals, etc., requires knowing how both mean and variance of queue size vary over time. Microscopic simulation can explore variability but is computationally demanding and gives only sample results. A computationally efficient approximation to the mean is used in many modelling tools, but only empirical extensions for variance in particular situations have been available. The paper derives theoretical formulae for time-dependent and equilibrium variance, believed to be novel and to apply generally to queues covered by the Pollaczek–Khinchin mean formula, and offering possible structural insights. These are applied in an extended approximation giving mutually consistent mean and variance estimates with improved accuracy. Tests on oversaturated peak demand cases are compared with Markov probabilistic simulation, demonstrating accuracy (R^2?>?0.99) for typical random, priority-like (M/M/1) and traffic-signal-like (M/D/1) queues. Implications for risk analysis, planning and policy are considered.     

Planning guidelines for metro–bus interchanges by means of a pedestrian microsimulation model

The big paradigm for cities nowadays is to study the movement of pedestrians at the interface between metro and bus systems – metro–bus interchanges. When these interchanges are not well designed, walking is inefficient and can be unsafe for pedestrians. This paper analyses, by means of a pedestrian microsimulation model, metro–bus interchange spaces in order to propose planning guidelines for the city of Santiago de Chile. Specific objectives are (1) to identify the variables that provide efficiency and safety in those spaces; (2) to simulate different scenarios using the pedestrian simulation model LEGION; (3) to propose planning and design guidelines for pedestrian spaces at metro–bus interchanges; and (4) to contrast the recommendations in the recently opened terminal station on Line 1 of Metro de Santiago: Los Dominicos Station.     

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。