新建结构与运营地铁车站接驳关键技术

以深圳地铁新建3号线老街站换乘综合体与运营地铁车站接驳工程为实例,对运营车站临时加固防护、分部切割既有结构、新旧结构接驳等关键技术展开论述。提出运用金刚石绳锯与金刚石水钻相结合的一种静力切割工艺,很好地解决了该工程作业环境复杂、技术要求高、风险大等难题,安全、高效地完成了新建结构与运营地铁车站接驳工程。     

Commuters’ willingness-to-pay for improvement of transfer facilities in and around metro stations – A case study in Kolkata

Although several cities in India are developing the metro system, there are lacunas associated with transfer facilities in and around metro stations. The present work aims to investigate the perception of commuters of Kolkata city, India in terms of their willingness-to-pay (WTP) for improvement of transfer facilities. A stated preference survey instrument was designed to collect choice responses from metro commuters and the database was analysed by developing random parameter logit (RPL) models. The decomposition effects of various socioeconomic and trip characteristics on mean estimates were also investigated in random parameter logit models with heterogeneity. The work indicates significantly high WTP of metro commuters as compared to the average metro fare for improvement of various qualitative attributes of transfer facility such as ‘facility for level change’, ‘visual communication’, ‘pedestrian crossing’, and ‘pedestrian environment’. The WTP values are also found to vary across different groups of commuter formed on the basis of ‘trip purpose’, ‘monthly household income’, ‘station type’ and ‘metro fare’. ‘Work trip’ commuters are found to have higher WTP for improvement of access time, pedestrian environment and use of an escalator over the elevator. On the other hand, ‘high-income group’ commuters have shown higher WTP for improvement of access time, pedestrian crossing, and pedestrian environment. While ‘high fare group’ commuters have higher WTP for access time and pedestrian environment, heterogeneity is also observed in WTP for facility for level change, pedestrian crossing, and pedestrian environment across commuters using different ‘station type’ (underground, at-grade, and elevated). The findings from the study provide a basis for formulating policies for the improvement of transfer facilities in and around metro stations giving due attention to the preference of commuters having different socioeconomic and trip characteristics.     

CSM水泥土搅拌隔离桩在地铁基坑紧邻桥桩时的保护效果研究

为研究隔离桩在地铁车站基坑紧邻桥桩时的保护效果,避免基坑开挖对桥桩产生不利影响,采用二维数值模拟的方式对CSM水泥土搅拌桩在天津地铁某车站的应用进行分析,研究隔离桩长度、布设位置、无侧限抗压强度等参数对于桥桩水平及竖向变形的影响。研究认为:隔离桩采用合理桩长并具备一定强度时对邻近基坑的桥桩保护有一定的效果,能够在一定程度上控制桥桩的水平与竖向变形,可为类似工程设计和施工提供参考。     

地铁车辆辅助逆变电源分析研究

分析直接逆变方式、斩波降压逆变方式、两重斩波降压逆变方式地铁车辆辅助逆变电源的电路结构方案。结合北京"复八线"地铁车辆进口辅助逆变电源的技术条件,介绍DC750V国产化地铁车辆辅助逆变电源的研制方案和主要技术特点。给出方案的试验波形。     

天津地铁既有车站改建设计

通过对天津地铁1号线既有车站改建的实例分析,论述了既有地铁车站改建的设计方法,提出了对于其他地铁既有项目也会面临的局部改建和设备更新的问题。地铁车站的设计应以预测规定年限的客流量为依据,具有科学性、可行性、经济性和前瞻性。     

故障区段判断和隔离方法

本文简要介绍了配线自动化系统中故障区段判断和隔离方法的基本原理,并论述了该方法的实施步骤。微机综合保护测控装置的直接I/O功能,使得将该方法用于地铁供电系统中成为可能。     

砂层地铁车站暗挖施工技术研究

北京地铁5号线磁器口车站主体结构大部分位于粉细砂、细砂及中粗砂层中,结构埋深10m左右,采用中洞法施工。由于地质条件多为砂层,施工环境复杂,对地表沉降要求严格,主要阐述车站主体的施工方法,对施工各阶段地表沉降原因进行分析,提出车站施工中的相关建议。     

移动式布料皮带机在双护盾TBM出碴中的应用

隧道TBM施工采用有轨运输方式出碴时,掘进过程中矿车卸碴布料涉及工序较多,且牵引列车编组的内燃机车持续运行会增加尾气排放,造成隧道内空气污染。应用于青岛地铁隧道施工的双护盾TBM的后配套配置了移动式布料皮带机,该皮带机可实现往复移动和正反向运行为矿车卸碴布料。对该移动式布料皮带机的工作原理、结构组成、移动方式、张紧方式和驱动方式等进行研究,并分析其应用效果。实践证明,该技术应用于TBM后配套出碴可行、实用,简化了施工工序并提高了工作效率。     

大直径中空孔直眼掏槽微振动爆破参数研究

为最大限度减小掏槽区的爆破振动对地表建筑物的扰动,以青岛地铁3号线太延区间下穿伊美尔整形医院段为背景,通过理论分析和现场试验,对大直径中空孔直眼掏槽的中空孔孔径、掏槽装药炮孔数目、首响孔与中空孔距离、逐孔起爆时差和中空孔布设位置各爆破参数进行探讨。结果表明:在断面中下部位布置直径为120~150 mm的中空孔,环形布置4个掏槽眼,首响孔距中空孔200~350 mm,逐孔起爆时差宜在40 ms以上,可使掏槽爆破振速得到有效控制。     

全断面硬岩地层盾构隧道管片上浮控制技术研究

为了解决盾构在全断面硬岩地层中管片上浮的问题,确保管片衬砌的施工质量,结合广州7号线某全断面硬岩段的盾构施工,从力学条件和空间条件等方面分析了导致管片上浮的原因和机制,从盾构施工和设计等方面提出了减小管片上浮的新措施。包括:采用豆砾石回填灌浆工艺进行管片壁后填充、利用止浆环与隔水环防止浆液流失、半敞开式掘进提高同步注浆的填充效果、采用前盾底部设计千斤顶防止盾构栽头等。