双层隧道土建结构设计关键技术探讨

双层隧道为大断面隧道工程,结构新颖,施工工艺较为复杂,目前国内采用新奥法设计施工的双层隧道工程成功案例较少,可借鉴经验不多.本文结合温州某在建城市主干道双层隧道工程,分别从设计技术标准的采用、横断面设计、隧道结构设计、洞口过渡段设计、施工方案各角度对双层隧道进行论述,相对于普通公路隧道工程来讲,具有一定的创新.希望通过本文的分析与总结,为今后类似的双层隧道设计提供一些借鉴.     

分离式特长隧道结构设计探讨

结合工程实践经验,对隧道结构设计相关要求进行了阐述,并以某分离式特长隧道为实例,总结该隧道的明洞和暗洞的设计过程及方法,为同类工程提供参考借鉴。     

甬江水底隧道工程实施中几个值得商榷的问题

笔者通过对组织实施软土基沉管法水下隧道－浙江宁波甬江水底隧道工程建设全过程的体会和认识，分别将工程的前期工作、设计班子组建、勘察的广度、深度、试验项目、北引道工程、江中管段工程、土坞工程、竖井工程、南、北护岸工程和南引道工程原设计进行回顾和总结，某种意义上是对工程设计进行后评估，是很有必要和具有现实意义的。     

上海软土隧道盾构施工技术专家系统综述

由上海隧道工程股份有限公司、上海市地铁总公司、同济大学和上海大学等单位结合上海地铁１号线工程，成功地开发了“软土隧道盾构施工技术专家系统”。研究人员在归纳总结国内外隧道盾构施工的理论研究、工程实践的基础上，形成了专家系统的知识源，然后应用先进的计算机技术，开发了盾构型式及辅助施工法的选择、预测地面变形、优化施工参数、控制地层变形和保护建筑设施的软件程序，实现了人机对话，经地铁１号线区间隧道工程应用     

地铁隧道施工对地表沉降影响的优化控制分析

基于控制理论,建立了城市地铁隧道工程地表沉降的理论控制模型;结合动态规划原理,提出了城市地铁隧道工程地表沉降动态最优控制策略制定程序.文章对深圳地铁大剧院站～科学馆站区间三连拱隧道工程地表沉降的控制问题进行了理论探索,取得一些有意义的成果,为该工程的顺利实施提供了重要的依据并具有一定的指导作用.     

高海拔寒区隧道建设管理中应注意的问题

对隧道工程建设管理中的工程合同、工程进度、工程质量、工程费用方面应注意的问题进行了阐述.     

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.     

盾构法与矿山法相结合施工技术

深圳地铁一期工程益田～香蜜湖区间隧道,采用盾构法与矿山法相结合的施工技术,既缩短了工期、降低了工程成本,又维持正常交通,保护了沿线建筑物,达到了保护环境的目的,介绍施工步骤和要点,可供类似工程参考。     

博斯普鲁斯海峡公路隧道开始掘进

博斯普鲁斯海峡隧道工程于2014年4月19日开始盾构掘进作业。工程建于伊斯坦布尔欧洲区的Kazlicesme和亚洲区的Goztepe之间。隧道段全长约5．4km，为单管双层4车道盾构隧道（见图1）。     

地铁重叠隧道施工顺序研究

文章以深圳地铁三号线老-东区间盾构隧道工程为背景,采用有限元数值模拟研究方法,对地铁重叠隧道段在地表无任何建筑物和地表有房屋基础两种工程条件下,采用先上洞后下洞和先下洞后上洞两种施工顺序的盾构区间隧道施工全过程的力学行为进行了分析对比。通过分析,揭示出了相关的研究成果与实际施工顺序不同的关键所在,可为今后类似工程的设计与施工提供参考。     

Bicycles in large cities in China

Bicycles are a main means of transport in China. This paper discusses several aspects of the current situation and future policy, including the production of bicycles, their possession and utilization in typical large cities, the reasons for their importance in communication, the advantages and problems of bicycle traffic, and two different opinions on solving the existing problems. The paper also deals with road design for bicycles and their regulation in China's cities.     

Travel choices in alcohol-related situations in Virginia

Transportation - Using survey data from 3004 respondents aged 21 and older in Northern Virginia, Richmond, and the Tidewater area, this paper identifies factors associated with respondents’...     

Parking policies in large cities in Germany

This article deals with highly motorized large West German cities of about 200,000 inhabitants and more, which usually provide reasonable public transport systems. Illegal parking with shares of about 40 to 50% of the total parking is widespread in the parking problem areas of those cities, especially in the inner-city residential and mixed-use areas. Parking spaces are demanded by residents, employees, customers and visitors, and by delivery and service traffic. The different characteristics of parking demands by different user groups are discussed. The total parking supply consists of public and private spaces. The share of private spaces is about 40 to 50% of the total parking spaces in German cities. The amount of car traffic generated by a parking space depends on parking duration and parking turnover, as well as on search traffic. So the change of a space from long-duration use of an employee to short-duration of customers — as often discussed in parking concepts — generates at least five-fold car traffic. The measurements and effects of parking control of public spaces as well as the parking regulations in zoning ordinances, restrictions on the construction of new private parking spaces and park-and-ride are discussed. Finally, a parking concept methodology — using the example of Frankfurt am Main — is discussed.     

Role of transport in rural development in Africa

Rural Africa is starved of transport services. The transport routes run towards the export enclaves and the coast.

The political, social and developmental rural transport benefits are discussed. Rural transport will help (i) integrate the country and ease its governance; (ii) widen markets; (iii) induce increased agricultural output, through new technologies, reduced transport costs, etc. The transport cost savings should be passed on to rural firms and producers. The paper warns against their accruing only to middlemen — agricultural parastatals inclusive, thereby stifling the benefits to production. This could happen under some forms of pan‐territorial pricing. Negative aspects of road development, e.g. the substitution of local goods by imports, increased migration and noise, are noted.

The place and role of project appraisal in rural road planning is acknowledged. The broad‐based development packages approach associated with Integrated Rural Development Projects has, despite its attractions, some pitfalls. It favours well established villages and ignores distribution benefits within villages.

Project appraisal can be used to justify socially uneconomic transport developments. However, rural road investment projects with immediate negative returns are unlikely to be funded. Given clear priorities, short of elaborate cost/benefit analysis, obvious road investments choices can be made by the local community. Greater public accountability of transport planners and peoples’ participation in determining rural transport needs and priorities is emphasized. Increased rural road maintenance especially through self‐help schemes and increased use of traditional modes of transport, e.g. walking, animal and water transport, is recommended.     

Changes in transport risk perception in urban populations in Norway from 2004 to 2013

Urban populations transport risk perception is interesting because it is associated with travel mode choices and use. This study investigates changes in transport-related risk constructs in the urban population in Norway in 2004 and 2013, and describes whether people perceive private or public to be associated with the highest risk. The results are based on self-completion questionnaire surveys conducted in two independent representative samples living in the same urban areas in 2004 (n?=?592) and 2013 (n?=?1035). Overall, the respondents perceived the risk as lower in 2013 than in 2004. For both time periods, people consistently assessed the risk constructs related to private motorized transportation as higher than corresponding risk in public transportation. The findings suggest that while transportation risk perception in urban populations may change over time, the pattern that private motorized transportation is associated with a higher perceived risk than public transportation remains stable.     

Logistics opportunities in Asia and development in Taiwan

The economy in Asia is growing rapidly. As a consequence, transportation and communication technologies and the changing needs of customers and shippers have resulted in Asian and Taiwan's logistics being in transition. This paper discusses why logistics changes, and explores the opportunities for Asian logistics development. The issues of logistics perspectives of private sectors in Taiwan are then raised. Finally, logistics development in Taiwan is described.     

Mapping minibuses in Maputo and Nairobi: engaging paratransit in transportation planning in African cities

ABSTRACT

Often called paratransit because of their flexible stops, schedules and routes, minibuses make up the bulk of public transport in African cities. Despite their ubiquity and importance, these systems are poorly understood by transportation planners who tend to focus on large-scale urban infrastructure projects such as highways, commuter rail or bus rapid transit systems. The assumption within much of this planning is that these minibus systems are barriers to change and will become at most secondary “feeder” buses within large-scale projects, but structured plans detailing this vision are lacking. This paper argues that frequent failure to collect data and value important paratransit systems as a critical part of transportation in their own right is deeply problematic from the point of view of equity, access and inclusive and effective planning. We ask whether the growing number of bottom up mapping projects of minibus systems can disrupt this status quo. By comparing two mapping projects, Digital Matatus in Nairobi and the Mapa Dos Chapas in Maputo, we find that inclusive, collaborative mapping can help render these minibuses more visible in planning and provoke more grounded and inclusive “planning conversations” on multi-modal integration, passenger information and minibus upgrading, all key but relatively marginalised aspects of creating accessible, low emission, high quality and safe public transport in African cities.     

Passenger rail in North America in the light of developments in Western Europe and Japan

Because of different geo‐demographic and economic conditions, the impact of the new passenger modes (road and air) on rail travel was much larger in North America than in Europe. In 1960s and 1970s, as the railway share of intercity traffic in North America shrunk to a negligible one or two percent, the passenger trains were abandoned by private railway companies and taken over by state organizations, which have continued to operate traditional trains and generate mounting losses. On the technology side, no attempts have been made to improve competitiveness of trains vis‐a‐vis automobiles and airplanes.

In Europe and Japan, the railways responded to the challenge by (i) upgrading the performance (speed) and comfort of traditional trains operating on existing tracks and (ii) developing trains which could, on short and intermediate range distances, compete successfully, in terms of speed and economy, with the road and air modes. The Japanese (Shinkansen trains) and French (TGV trains) experience clearly shows that trains operating on dedicated lines at average speeds of 150 to 200 km/hr provide a superior transportation service and economy on high‐traffic intercity routes of up to about 500 km length. In this paper the factors responsible for the present status of passenger rail in North America are analysed, the current policies in the U.S. and Canada are evaluated in the light of experience to date and developments abroad, and suggestions for a long‐term passenger rail policy are made. This includes examination of (i) the viability of continued subsidization of traditional train services, (ii) the viability of operation of faster trains on existing tracks, (iii) the scope for introduction of modern, fast trains on dedicated lines in high‐density, intercity corridors, (iv) the application of fast trains as access to major airports and integration of airports with fast intercity lines, and (v) the impact of energy (oil) consumption in transportation.

     

美国煤浆体管道检测方法的新进展

从煤浆密度和浓度、流变参数和粒子带电量测量3个方面简要地总结了美国煤浆检测技术的新方法、新仪器的发展状况,分析了其发展特点。这将有助于促进国内煤炭浆体管道输送的发展。     

Gender inequality in mobility and mode choice in Pakistan

Using the nationally representative dataset of the 2007 Pakistan Time-Use Survey, this paper examines gender differences in daily trip rate, mode choice, travel duration, and purpose of travel, which are previously unreported because of limited data availability. Wide gender mobility gaps are observed in the country, where women are less likely to travel, are half as mobile as men and may rely heavily on walking. The particular social and cultural context of the country, that renders women as private, secluded and family honor, seems influential in shaping their mobility and choice of activities. Demographic factors such as age, household income, and marital status significantly decrease female mobility levels. Hence, these findings call for a gender-based culturally responsive transportation policy in the country.