摘要
北京地铁14号线将台站采用大直径土压平衡盾构先行通过,扩挖形成地铁车站。通过数值模拟进行受力转换计算并与实际监测数据进行对比分析认为:导洞开挖引起的地表沉降要大于大盾构施工引起的地表沉降,且最大沉降点逐步由导洞上方移动到盾构上方,体现出群垌效应;初支扣拱弯矩最大部位发生在初支与盾构K管片接触部位,是受力转换的关键;导洞开挖和初支扣拱阶段引起的地表沉降约占总沉降量的85%,是沉降控制关键环节。提出了扩挖施工关键技术:盾构管片拼装施工、初期支护、管片拆除、二衬施工。
Beijing metro line 14 Jiangtai station using large diameter earth pressure balance shield pass first,then dig to form a subway station. Using numerical simulation and compared with the actual monitoring data to analysis Force transformation: The surface subsidence caused by the pilot tunnel excavation is greater than the ground settlement caused by shield construction, and the maximum subsidence point gradually elaborated from the upper pilot tunnel moving into the upper shield reflect group tunnel effect; the largest bending moment occurred in the contact area of shield segment K, is the key force transformation; Ground subsidence caused by Pilot tunnel excavation and the buckle arch stage accounted for about 60% to 85% of the total settlement, which is a key link in the process of settlement control. Proposed the expansion construction key technology: shield tunneling construction, the buckle arch stage, demolition segment, two lining construction.
出处
《土木工程学报》
EI
CSCD
北大核心
2015年第S1期293-296,共4页
China Civil Engineering Journal
基金
国家自然科学基金重点项目资助(51134001
U1234210)
中央高校基本科研业务费专项资金资助(No.2012JBM081)
关键词
大直径盾构
扩挖
施工工艺
受力转换
large diameter shield
enlarged excavation
construction technique
stress transformation
