不同地层条件盾构始发对地表沉降影响规律研究  

Study on Rules of Influence of Shield Launching in Different Strata on Ground Surface Settlement

作　　者：赵耀强[1] 李元海[1] 朱世友 林志斌[1] 

机构地区：[1]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221008 [2]中铁隧道勘测设计院有限公司,天津300133

出　　处：《隧道建设》2011年第4期463-469,共7页Tunnel Construction

摘　　要：针对盾构始发施工造成地表沉降过大、导致工程事故时有发生的问题,采用岩土通用软件FLAC3D建立盾构始发三维模型,对北京、杭州、南京和上海4个典型地区代表土层盾构始发施工的全过程进行模拟计算,总结出各典型地区盾构始发施工对地表变形的影响规律,并提出相应的施工建议。研究结果表明,相同施工条件下:1)不同地层盾构始发地表沉降差别较大,黏性土较砂性土沉降槽影响范围相对较大,中心点沉降量相对较小;2)典型地区均为黏性土条件下地表沉降较小,非黏性土地层条件下地表沉降较大且在横向基坑边界处地表差异沉降较大;3)典型地区从地表沉降控制效果由好到差排序为北京>南京>杭州>上海。Accident often happens due to the serious ground surface settlement caused by shield launching.3D shield-launching model is established by means of FLAC3D program.The full course of shield launching in typical strata in Beijing,Hangzhou,Nanjing and Shanghai is simulated,the rules of the influence of the shield launching in the above-mentioned typical strata on the ground surface settlement are summarized and countermeasures are proposed.The study result shows that under the same construction conditions： 1） the ground surface settlement induced by shield launching in different strata varies much,the scope of the influence of the settlement trough in cohesive soil is larger than that in sandy soil and the settlement at the central point in the case of cohesive soil is smaller than that in the case of sandy soil.2） In the case of cohesive soil in the above-mentioned typical regions,the ground surface settlement is small;in the case of non-cohesive soil,the ground surface settlement is large and the differential ground surface settlement at the transverse boundary of the foundation pits is large.3） The effect of the control of the ground surface settlement in Beijing is the best,that in Nanjing takes the second place,that in Hangzhou takes the third place and that in Shanghai is the worst.

关 键 词：盾构始发 地层参数 地表沉降 数值模拟 

分 类 号：U45[建筑科学—桥梁与隧道工程]