多圈管冻结壁形成和融化过程冻胀力实测研究  

Formation and Thawing Processes of a Multi-Coil Pipe's Frozen Wall

作　　者：汪仁和[1] 张瑞[1] 李栋伟[1] 

机构地区：[1]矿山地下工程教育部工程研究中心,矿山建设安徽省重点实验室,安徽理工大学土木建筑学院,安徽淮南232001

出　　处：《冰川冻土》2010年第3期538-542,共5页Journal of Glaciology and Geocryology

基　　金：高等学校博士点专项科研基金项目(200803610004);国家“十一五”支撑计划项目(2007BAK28B04);国家自然科学基金项目(50804002,40972188)资助

摘　　要：为获得多圈管冻结壁形成与融化过程中冻结壁内部冻胀力发展特性和孔隙水压力变化规律,进而分析冻结壁力学性态及安全性,在淮南某煤矿开展了冻结壁冻融过程中内、外部冻胀力和孔隙水压力的现场实测研究.实测结果表明:在地层冻融过程中,冻结壁内、外部形成了不均匀的冻胀应力,测试地层最大冻结压力达6.0 MPa,为初始地压的2.4倍;当井筒开挖至测试层位时地层冻结压力呈线性降低;随着浇筑外层混凝土井壁,冻结压力又有回升,当冻结壁融化后地层冻胀力为零,井壁恢复受水土压力作用.孔隙水压力变化经历了静止孔隙水压力和冻结过程的超静孔隙水压力两个阶段,超静孔隙水压力达到4.0 MPa,约为静止孔隙水压力的2.0倍.For obtaining the development characteristics of frost-heaving forces and pore water pressure on frozen wall in the formation and thawing processes of a multi-coil pipe＇s frozen wall and further studying the mechanics property and safety evaluation of frozen wall,an in-situ measurement of internal and external frost-heaving forces and pore water pressure were carried out in a coal mine in Huainan Municipality.The measurement shows that uneven frost-heaving forces exert on the inside and outside of the frozen wall in the earth freezing and thawing processes,with the maximum earth freezing pressure of 6.0 MPa,2.4 times of the initial earth pressure.The earth freezing pressure decreases linearly when the shaft is excavating to the test horizon,then the earth freezing pressure increases again slightly with the sidewall concreting,and finally the freezing pressure goes to zero when the frozen wall thawing out and then the initial ground pressure state recovers.In the test process,the pore water pressure experienced a static pore water pressure stage and an excess pore water pressure stages,with an excess pore water pressure of 4.0 MPa,2.0 times of the static pore water pressure.

关 键 词：现场实测 多圈管冻结 冻结压力 孔隙水压力 冻融过程 

分 类 号：TU443[建筑科学—岩土工程]