马平路板可隧道纵坡设计方案比选

隧址区的地形条件是选择隧道路线纵坡的重要影响因素,隧道路线纵坡方案一旦不能和地形相适应,会影响工程数量、造价及运营安全。文章结合广西马山至平果高速公路板可隧道工程实例,从通风、照明、地质条件、施工条件及工期等方面,对该隧道路段拟定的两个纵坡设计方案进行综合比选,提出了典型山区地形条件下的隧道路线纵坡设计的注意事项,为类似地形的隧道路线纵坡设计提供参考。     

基于BIM融合技术的复杂地质路段综合设计研究与应用

文章针对某高速公路古滑坡及岩溶隧道的综合设计难题,开展了激光雷达、实景三维及三维地质建模等BIM融合技术研究,对该工程复杂地质路段的古滑坡对象、岩溶隧道对象分别进行了三维实体建模,并开展了基于BIM的体系化技术应用,确保了复杂地质路段工程安全,取得了较好的应用效果.     

某山区高速公路隧道弃渣填筑路基的应用研究

文章以某山区高速公路为例,对隧道弃渣在路基填筑中的应用进行研究,针对该试验路段特点及工程地质情况,制定合理的施工方案及施工方法,对试验路段碎石路基进行分层填筑施工,并通过相关试验得出隧道弃渣填筑路基的应用效果。     

广西高速公路木冲隧道交通安全性分析

长大隧道是高速公路的控制路段,其运营安全对高速公路畅通和安全有重要影响。文章通过研究木冲隧道交通事故分布特征,分析了长大隧道发生交通事故的原因,提出了改善木冲隧道交通安全状况的工程措施和管理建议,其对提高木冲隧道运营安全性具有指导意义。     

镇清高速特长隧道比选及长大纵坡方案设计研究

长大纵坡路段是山区高速公路事故高发地。文章针对云南省镇康至清水河高速公路在连续长大纵坡路段存在的越岭特长隧道选择、爬坡车道设置、避险车道设置等关键性问题,从平均纵坡、运行速度模拟、货车下坡制动温度等方面进行分析,提出优化纵断面设计、合理选择越岭隧道方式、合理设置避险车道等措施,为山岭重丘区高速公路在连续长大纵坡路段的方案设计提供参考。     

信息园地

1国道214线共和至玉树高速公路一期工程开工建设青藏高原多年冻土地区的首条高速公路,共和至玉树高速公路一期工程开工仪式5月9日在玉树结古镇举行。共和至玉树高速公路是国道214线改扩建工程一期工程,全长647.026km,公路沿线平均海拔4100m左右,路线全线穿越季节性冻土和多年冻土路段,其中,穿越多年冻土路段长190km,占总里程的30%.全线桥梁和隧道总长56km,占总里程的9%.设计时速     

高速公路单向交通隧道内最大纵坡设计研究

文章根据对隧道内施工运输、排水和通风等最大纵坡控制因素的分析,提出了隧道内单向交通连续上坡路段最大纵坡的建议值,以及长大隧道内增大坡度的技术措施,可供公路设计参考和借鉴。     

隧道工程的动态设计与信息化施工研究

鉴于隧道建筑理论体系尚不成熟的情况,需要强化隧道工程动态设计与信息化施工。对隧道工程动态设计与信息化施工内容和流程进行了分析和研究。施工信息反馈内容分为地形环境、地质、监测变形和建设施工需求等;动态设计内容分为隧道支护结构、隧道尺寸、施工方法、辅助工程措施、临时工程等。可供广大设计与施工者参考。     

西气东输靖边至临汾段隧道工程的设计与施工

西气东输管道工程从靖边至临汾段共设计有12座山岭隧道,其中11座隧道穿越黄土地层,1座隧道穿越岩石地层.文章介绍了隧道的工程地质和水文地质概况以及设计原则和施工方法,总结出了天然气管道隧道工程的设计与施工特点.     

广深港高速铁路狮子洋水下盾构隧道修建技术

从环保要求与可持续发展战略考虑,水下隧道必将是我国跨江越海交通工程的主要选择方式。广深港客运专线狮子洋隧道为我国首座水下铁路隧道,也是我国第一条特长水下隧道,其设计速度达350 km/h,该隧道为广深港高速铁路的关键性工程。针对该隧道的工程地质环境和采用的盾构法施工技术,特别是该隧道在我国首次采用的盾构对接方法施工,本文重点介绍了该隧道修建的有关设计与施工的技术,并提出了相应的措施。     

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。     

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.     

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.     

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。