摘要
研究目的:随着我国新型城镇化战略的深入实施,中心城区人口不断聚集,既有地下空间的改造、拓建,是实现地下空间资源充分利用的重要手段,城市轨道交通地下空间的网络化拓建正是典型代表。基于目前地下空间改扩建类型及存在问题的调研,对新建与改拓建地下工程的差异进行系统分析,提出既有城轨交通地下空间横向与竖向拓建关键技术。研究结论:(1)从三个维度对城市轨道交通地下结构的改拓建工程进行了分类,从横向连通接驳、竖向增层与交叉穿越两个方面对各类城轨交通地下工程的拓建技术进行了分析;(2)研究提出的大刚度C型咬合梁在接驳连通方面可实现新旧结构接缝部位的零渗漏目标,明确了竖向支撑是实现既有隧道扩挖期间拱顶应力释放、沉降变形控制的关键;(3)提出了基于中洞法的竖向荷载主动托换体系可实现运营车站下方零距离增层拓建,进一步针对运营隧道上方的跨越拓建,提出了基坑或竖井跳挖技术,可有效应对隧道上方地层卸载引起的回弹隆起变形;(4)本研究结论可为地下空间改扩建工程提供借鉴。
Research purposes:With the deepening implementation of China's new urbanization strategy,the population continues to concentrate in central urban areas.The renovation and expansion of existing underground space represent a crucial means of achieving the full utilization of underground spatial resources,with the networked expansion of urban rail transit underground space serving as a typical example.Based on the investigation of current types of underground space expansion projects and their associated issues,this paper systematically analyzes the differences between newly constructed and expanded underground projects,and proposes the key technologies for horizontal and vertical expansion of existing urban rail transit underground space.Research conclusions:(1)The renovation and expansion projects for underground structures in urban rail transit can be classified from three aspects.The expansion technologies for various types of underground projects in urban rail transit are analyzed from two aspects:horizontal connection and joint,vertical expansion(adding levels)and crossing traversal.(2)The research proposes that the large-stiffness C-shaped interlocking beam can achieve zero leakage at new-to-existing structure interfaces in horizontal connection and joint projects.It identifies vertical supports as the key element for controlling stress release at the tunnel vault and mitigating settlement deformation during the excavation and expansion of existing tunnels.(3)For zero-distance vertical expansion beneath operational metro stations,the study proposes an active vertical loadtransfer underpinning system utilizing the center pilot tunnel method.Furthermore,for over-crossing expansion above operational tunnels,it introduces the skip excavation technique for foundation pits or shafts,which can effectively mitigate rebound heave deformation induced by stratum unloading above the tunnels.(4)The research findings can provide valuable references for upcoming underground space renovation and expansion projects.
作者
戴志仁
张莎莎
李国良
邹维列
冯虎
李明宇
贾建伟
杨志全
韩雪
DAI Zhiren;ZHANG Shasha;LI Guoliang;ZOU Weilie;FENG Hu;LI Mingyu;JIA Jianwei;YANG Zhiquan;HAN Xue(Chang’an Universirty,Xi'an,Shaanxi 710064,China;China Railway First Survey&Design Institute Group Co.,Ltd.,Xi'an,Shaanxi 710043,China;State Key Laboratory of Intelligent Construction and Maintenance for Extreme Environmental Geotechnical and Tunnel Engineering,Xi'an,Shaanxi 710043,China;Wuhan University,Wuhan,Hubei 430072,China;Zhengzhou University,Zhengzhou,Henan 450001,China;China Construction Sixth Engineering Bureau Co.,Ltd.,Tianjin 300012,China;Kunming University of Science and Technology,Kunming,Yunnan 650093,China)
出处
《铁道工程学报》
2025年第10期89-95,共7页
Journal of Railway Engineering Society
基金
国家自然科学基金面上项目(52478421)
2024年陕西省重点研发计划(2024SF-YBXM-659)
中国铁建股份有限公司地下空间利用领域科研计划项目(2024-W30,2024-W22-03)。
关键词
轨道交通
地下空间
拓建
C型咬合梁
主动托换
跳挖竖井
metro line
underground space
renovation and expansion
C-shaped beam
active vertical load-transfer underpinning
ship excavation shaft
