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621.
隧道式复合锚碇的作用机理   总被引:2,自引:0,他引:2  
采用原位模型试验和有限元(ANSYS软件)数值分析,研究了悬索桥带预应力岩锚的隧道式锚碇系统的承载机理,根据施工动态过程反演确定关键参数.锚碇-围岩、岩锚-注浆体-围岩相互作用力学行为采用无厚度接触单元模拟.结果表明,岩锚初始预应力控制着锚碇体和岩锚对主缆荷载的分担和参与时机,岩锚存在最小自由段长度,以均匀分布和传递围岩应力,形成岩石锚固墙新围压效应.  相似文献   
622.
综合客运枢纽布局规划体系探讨   总被引:1,自引:0,他引:1  
布局规划是综合客运枢纽规划建设的顶层设计,文章结合相关课题的研究与实践,对综合客运枢纽布局规划体系涉及的内容、原则和要求、思路和方法、选址要求等进行了归纳和总结,以供参考.  相似文献   
623.
随着城市经济的不断发展,机动化进程的不断加快,城市交通问题越来越突出。“交通7+1论坛”第五次理事会会议围绕系统工程与城市交通主题,以北京市和深圳市为案例,重点探讨了优先发展公共交通,解决城市交通问题的战略,从网络线路、换乘枢纽、优先通行、管理体制等方面进行了深入的分析,并结合系统工程理论方法,提出了相关建议。  相似文献   
624.
发展绿色交通被国内外专家学者一致认为是缓解城市交通拥堵的根本途径。文章通过分析绿色交通的基本内涵以及与土地利用的相关关系,以历史文化名城扬州为例,探讨基于土地利用的绿色交通发展策略,并提出扬州市绿色交通系统规划布局方案。  相似文献   
625.
随着我国城市化、机动车化的进程不断加快,城市交通问题日益突出,特别是大城市的交通拥堵,为城市经济、居民生活和环境带来了巨大的影响。“交通7+1论坛”第二次理事会会议围绕城市交通规划、建设与管理主题,以北京市为案例,分析了北京城市交通的现状、问题与趋势,阐述了构建新北京交通体系的目标和战略措施。针对城市交通结构、公交优先、信息技术、需求管理等问题,探讨了应用复杂系统理论方法解决交通问题的思路与应用前景。  相似文献   
626.
Resilience theory has management implications useful when planning for cruise ship tourism. In small coastal communities, cruise ships often provide welcomed economic incentives that can bolster a waning economy. However, in some coastal communities, the magnitude and intensity of passenger visits can reduce social resilience and induce an economic regime shift that leads to rapid socioeconomic reorganization. The implications of such a regime shift are a loss of economic diversity, reduced social resilience, and a loss of social capital. Planning for cruise ship resilience increases the likelihood of successful coping strategies and addresses the socioecological changes inherent to a cruise ship destination. Both Holling's adaptive cycle and the four principals for building resilience established by Berkes and Seixas are fundamental to a successful management plan.  相似文献   
627.
In order to plan for, and achieve, a sustainable and accessible transport system, research and policies alike recognize a need to implement and enhance alternative transport options in favor of the private car. Moreover, these sustainable alternatives need to offer sufficient levels of accessibility regardless of where people live or work. We present and discuss an approach for capturing and evaluating perceived accessibility, with the ability to differentiate between individuals. Levels of perceived accessibility are compared before and after a fictive car use restriction, and between residential areas, using data from 2711 residents of Malmö, Sweden. A main conclusion is that levels of perceived accessibility become significantly lower for car users when they are limited in their options for daily travel. The difference is more substantive for frequent car users, who already travel less by sustainable modes today. There are also significant differences in levels of perceived accessibility in the restricted scenario, depending on where individuals live. These novel findings may not come as a surprise, but they emphasize the importance of including and analyzing perceptions of car users when designing accessible and sustainable transport systems. The paper ends with a discussion on how to facilitate the transition from current transport systems to an inclusive and accessible system.  相似文献   
628.
为探讨城市变化过程中线网规划的发展规律、变化趋势及优化方法,以大西安都市区为例,研究历次城市规划、线网规划主要技术指标特征,通过ROXY指数定量分析其变化特征并分析存在问题,结合研究对象特征提出未来线网优化思路并给出优化方案。经计算,ROXY指数在不同阶段的结果分别为161.75,16.20,-85.41,结果表明大西安都市区呈现"集中-分散"的发展趋势,需求特征日趋多样化。既有线网规划存在服务范围小、多网融合程度低、线网层次单一等问题,可通过发展多网融合、多层次多制式轨道交通来满足城市发展与交通需求的变化。  相似文献   
629.
Several factors contribute to short-duration unscheduled absences of bus transit drivers. This article aims to understand these factors at the aggregate level and to anticipate future total absence that will need to be filled for a large-size transit operator. The aggregate level is defined as the total number of regular driver absences per garage, day of week and time period that need to be covered by the extraboards. This study analyzes absenteeism data obtained from OC Transpo, the transit provider of the city of Ottawa, Canada. A multilevel regression model is generated to investigate regular drivers’ absences. The short-unscheduled absence is estimated in relation to temporal factors, drivers’ personal characteristics, aspects of assigned work, and service delivery characteristics. Furthermore, using the model’s coefficients, sensitivity analyses are conducted to demonstrate the advantages of this technique over traditional ones adopted by various transit agencies. This study provides transit planners and policy makers with a practical methodology that can be used to support extraboard planning practice and help reduce the incidence of missed trips due to absences while having the appropriate size of extraboard drivers.  相似文献   
630.
When discussing the future of cities, there is a tendency to focus on technology that will make cities and mobilities more sustainable. A bit further down the line the question of understanding or changing everyday practice arises – how to get people to transform their current mobility practice, or to adjust to the technologies introduced. As a key to understanding and changing practice I argue that storytelling plays a crucial role on different scales. In line with this, the concept of structural stories can be used to understand how specific framings of modes of transport guides everyday practices. To illustrate this, I will use the example of a concept of redesigning Copenhagen’s streets. On these streets space is redistributed so that pedestrians, cyclists and busses get more space, and more space is created for public places and city life. Consequently, the space allocated for cars and parking is scaled down.  相似文献   
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