伦敦道路拥挤收费政策

伦敦市于2003年2月在中心区实施了拥挤收费政策,该政策取得了良好的成效。简单介绍了伦敦市拥挤收费方案,概括了在拥挤收费实施过程中,伦敦市出台的主要政策措施;通过拥挤收费政策实施前后车流量、环境、商务活动的对比,归纳了拥挤收费政策的实施效果。此外,介绍了伦敦市拥挤收费政策的未来发展规划。最后,提出了伦敦市拥挤收费政策对于我国城市的经验借鉴。     

浅析地下水对公路隧道建设的不利影响

地下水可以通过对岩石溶蚀、软化以及与岩石、岩体构造的共同作用等方式,影响隧道围岩和初支稳定、破坏隧道衬砌结构受力安全及增加隧道运营养护难度。文章总结归纳了地下水对公路隧道施工和运营产生不利影响的作用方式,为工程技术人员进行隧道设计、施工提供参考。     

基于阈值分割法的地下工程防水板孔隙结构识别

利用X射线CT技术扫描地下工程高密度聚乙烯(HDPE)防水板,基于阈值分割法对获得图像进行分割处理,探讨该种分割方法在图像处理中的适用性。对经过处理的防水板试样置于显微CT设备上进行扫描,获得系列二维切片图像,利用阈值分割法对其中单张图像进行处理,得到较为理想的二值图像,对图像中孔隙进行标记,据此进行孔隙结构分析。结果表明:处理后图像中的大小孔隙可以被清晰识别;孔隙面积、孔隙率及孔隙连通性等指标整体水平较低;小孔隙个数最多,且小孔隙在孔隙总面积中占有很大比例,孔隙面积与其个数与直径有关。研究结果证实利用阈值分割法对显微CT扫描图像进行分割处理是可行的,为地下工程防水板材料微观研究提供方法上的参考。     

地下工程湿喷混凝土技术探讨

结合某隧道初期支护喷射混凝土的施工,介绍了湿喷混凝土技术在地下工程中的具体应用。     

输油管道腐蚀与杂散电流测量

阐述了直流杂散电流干扰对管道腐蚀的基本原理,针对直流杂散电流的特点及工程测试要求,设计了智能杂散电流测试仪并用于地下管道的工程测试中。实际应用表明,该仪表具有良好的性能。     

城市综合体地下车库机动车引导系统设计方法

因驾驶员受视觉环境的影响,城市综合体地下车库存在标志视认性不足、安全性不佳的问题．通过总结地下停车库机动车引导系统的设计经验,提出了地下车库机动车引导系统的设计流程,和根据建筑业态确定了设置引导标志位置与密度的方法;提出了地下车库机动车引导标志悬挂净空标准以及净空不足时的改善措施;针对机动车引导标志版面信息需求提出了优化设计原则及实施方法,并以某城市综合体地下停车库工程实例进行验证。     

沈阳地铁二号线五里河车站围护结构设计

介绍了沈阳地铁二号线五里河车站围护结构的选择过程,重点叙述地下连续墙的计算要点。     

地下连续墙在沈阳地铁中的应用

沈阳市某地铁车站距浑河较近,地铁结构底板埋深大,地下水水量丰富,地层透水性强,为防止流砂、管涌等现象,采用地下连续墙在该地进行支护取得了较好的效果,通过施工方案比选及施工优化,对地下连续墙在该区域的适用性及工程实践进行了初步探讨。     

A new measure of resilience: An application to the London Underground

The many varied views on resilience indicate that it is an important concept which has significance in many disciplines, from ecology to psychology to risk/disaster management. Therefore, it is important to be able to quantifiably measure the resilience of systems, and thus be able to make decisions on how the resilience of the system can be improved. In this paper we will work with the definition, due to Pimm (1991), that resilience is “how fast a variable that has been displaced from equilibrium returns to it.” We will think of a system as being more or less resilient depending on the speed with which a system recovers from disruptive events or shocks. Here we consider systems which revert to an equilibrium state from shocks, and introduce a measure of resilience by providing a quantification of the rapidity of these systems’ recovery from shocks.We use a mean-reverting stochastic model to study the diffusive effects of shocks and we apply this model to the case of the London Underground. As a shock diffuses through the network, the human-flow in the network recovers from the shock. The speed with which the passenger counts return to normal is an indicator of how quickly the line is able to recover from the shock and thereafter resume normal operations.     

An exploration of shoppers travel mode choice in visiting convenience stores in the UK

Using data from over 2000 convenience store customers within and outside London, this paper explores how individuals access their convenience stores and how significant the influence of their socio-demographics, shopping types and trip chaining is to their mode choice in visiting the stores. Trip chaining is found to be crucial in influencing customers' mode choice and their visit frequency. The application of logit models also shows that frequent shoppers are the ones most likely to visit the stores on foot. Interestingly, the estimation results also show that the location's density, shopping types and the day of the week are not significant in influencing travel modes. Customers who live in the most deprived areas are less likely to use a private car in visiting the stores.