含水疏松砂岩隧洞冻结施工三维数值模拟  

3-D numerical simulation of frozen construction for tunnel of water content loose sandstone

作　　者：任伯锋 许健[1] 赵琨[1] 

机构地区：[1]甘肃农业大学工学院,甘肃兰州730070

出　　处：《甘肃农业大学学报》2014年第5期171-175,共5页Journal of Gansu Agricultural University

摘　　要：甘肃省引洮供水一期工程总干渠7#引水隧洞出口,采用冻结施工法成功穿越了含水疏松砂岩地层.应用大型有限元软件ANSYS,对冻结施工过程进行了三维数值模拟,分析了隧洞开挖过程中冻土帷幕的位移和应力分布情况,并提出了在施工过程中的一些安全保障措施,以便准确地掌握冻土温度的变化及冻土帷幕厚度发展状况,从而确定最优的开挖时间.分析结果及工程实践表明:最大拉、压、剪应力计算值分别为3.02、0.15和0.97Mpa,计算值相对于设计值的安全系数分别为13、1.9和1.5,并确定了其极值发生位置.同时也表明利用冻结施工法穿越含水疏松砂岩地层隧洞是合理的,研究结果可为引洮供水一期工程总干渠7#引水隧洞出口冻结施工提供理论支持,同时也为类似工程提供参考.By using artificially ground freezing process,No.7 tunnel export of Gansu YinTao Proj ect Phase-I successfully pass through water bearing loose sandstones formations.On the basis of three-dimen-sional numerical simulation for work progress through the application of the large finite element analysis software ANSYS,this paper analyzed the displacement and stress distributions of frozen soil curtain in the process of tunnel excavation,and put forward in the construction process of some security measures,in or-der to accurately grasp the changes and development of frozen soil thickness of soil temperature,as well as determine the optimal excavation.The analysis results and engineering practice showed that the maximum tension,compression,shear stress calculation values were 3.02,0.15 and 0.97 Mpa,the safety coefficient was 13,1.9 and 1.5 respectively,and its extremum position was determined.It also showed that using freezing method through the water tunnel was reasonable in loose sandstone reservoir.In this paper,some effective measures and reasonable advice were put forward for freezing construction by integrating on-site data monitoring,which provided theoretical support for the freezing construction of No.7 tunnel export of Gansu YinTao Proj ect Phase-I,and set up a reference for similar proj ects meanwhile.

关 键 词：含水疏松砂岩 引水隧洞 冻结法 数值模拟 监测 

分 类 号：TV311[水利工程—水工结构工程]