天津地铁盾构接收水平冻结实测与分析
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徐泽民1,2，韩庆华1,3，郑刚1,3(1 天津大学建筑工程学院， 天津 300072； 2 天津市地下铁道集团有限公司， 天津 300051；3 滨海土木工程结构与安全教育部重点实验室(天津大学)， 天津 300072)［摘要］天津地区地下3层及以下地铁车站，盾构掘进范围内主要为粉砂和粉土，并包含承压水层，水压高容易造成喷沙现象，引起开挖面失稳和地面沉降。为保护地面建（构）筑物，保证盾构安全接收，采用水平冻结方法加固地层。由于天津尚未开展冻土试验，在冻结设计中，冻土强度指标暂比照上海地区取值。通过对天津地铁3号线某区间左线盾构接收水平冻结设计与施工方案，以及土体和盐水温度实测数据进行分析，研究冻结方案的实际实施效果。实测结果表明，冻结设计满足冻结帷幕厚度和平均温度的要求，达到了加固土体和止水的效果，但由于盾构施工中未能有效地注浆封闭止水，造成带有泥沙的水流到刀盘位置，通过采取增加内排管冻结、增设明洞等措施后，盾构机安全进洞。［关键词］水平冻结； 盾构接收； 冻结帷幕； 平均温度中图分类号：TU3179文献标识码：A文章编号：1002848X(2012)11013204Field monitoring and analysis of horizontal freezing method for shield received in Tianjin metro tunnelsXu Zemin1,2, Han Qinghua1,3, Zheng Gang 1,3(1 School of Civil Engineering, Tianjin University, Tianjin 300072, China; 2 Tianjin Metro Group Co., Ltd., Tianjin 300051, China; 3 Key Laboratory of Coast Civil Structure Safety (Tianjin University), Ministry of Education, Tianjin 300072, China)Abstract: For three layers and more of underground subway station in Tianjin area, the range of shield driving mainly includes silt and silty soil, as well as artesian aquifer. High water pressure will easily cause sandblasting, instability of excavation face and surface subsidence. In order to protect the buildings and ensure safe shield received, horizontal freezing method is taken to strengthen the stratum. Because frozen ground experiments have not been taken in Tianjin, design of freezing method uses parameters of Shanghai. By analyzing horizontal freezing design and construction method of left line shield received in Tianjin No. 3 subway project, as well as temperature of ground and saline water, implementation effect was studied. The measured results show that freezing design satisfies the requirements of freezing curtain wall thickness and average temperature, reaches the effect of soil strengthened and water sealed. However, the gap between shield and segment has not been effectively sealed, water with silt flows into shield cutter head. By taking the measures of increasing inner freezing pipes and open tunnel, shield machine safely enters into the station.Keywords: horizontal freezing; shield received; freezing curtain; average temperature作者简介：徐泽民，博士，工程师，Email: tianjinmetro1@163.com。参考文献［1］ 陈瑞杰, 程国栋, 李述训. 人工地层冻结应用研究进展和展望［J］. 岩土工程学报, 2000, 22(1): 4044.［2］ 陈明雄, 郭荣根, 刘霆. 冻结技术在地铁及隧道工程中的应用［J］. 解放军理工大学学报, 2003, 4(6):972.［3］ 耿萍, 晏启祥, 何川，等. 隧道水平冻结施工过程的数值模拟［J］. 工程力学，2010,27(5):122126.［4］ 周晓敏, 苏立凡, 贺长俊. 北京地铁隧道水平冻结法施工［J］. 岩土工程学报, 1999, 21(3): 319322.［5］ 周晓敏, 王梦恕, 陶龙光，等. 北京地铁隧道水平冻结和暗挖施工模型试验与实测研究［J］. 岩土工程学报, 2003, 11(6): 676679.［6］ 岳丰田, 张水宾, 仇培云，等. 地铁联络通道冻结加固技术研究［J］. 地下空间与工程学报, 2006, 2(8): 13411345.［7］ 赵捷, 任云芬, 鲍鹏. 天津地铁联络通道冻结施工的数值分析［J］.河南大学学报：自然科学版，2007,7(4): 434437.［8］ 李大勇, 吕爱钟, 张庆贺，等. 南京地铁旁通道冻结实测分析研究［J］. 岩土力学与工程学报, 2004, 23(2): 334338.［9］ 秦爱芳, 李永和. 人工土层冻结法加固在盾构出洞施工中的应用［J］. 岩土力学, 2004, 25(增刊)：449452.［10］ 崔云龙. 简明建井工程手册［M］. 北京: 煤炭工业出版社, 2000:1173.
