围压对TBM滚刀破岩影响的数值模拟研究  

Numerical study on effects of confining stress on rock fragmentation by TBM cutters

作　　者：翟淑芳 曹世豪 周小平[2] 毕靖[2] ZHAI Shu-fang;CAO Shi-hao;ZHOU Xiao-ping;BI Jing(College of Civil Engineering and Architecture,Henan University of Technology,Zhengzhou 450000,China;Department of Civil Engineering,Chongqing University,Chongqing 400045,China)

机构地区：[1]河南工业大学土木建筑学院,河南郑州450000 [2]重庆大学土木工程学院,重庆400045

出　　处：《岩土工程学报》2019年第1期154-160,共7页Chinese Journal of Geotechnical Engineering

基　　金：河南工业大学博士科研启动基金项目(2018BS005);河南工业大学科学研究基金青年支持计划项目(2018QNJH27)

摘　　要：采用一种新的无网格数值计算方法—广义粒子动力学法(GPD),研究了水平方向围压为0,5,10,15,20 MPa条件下,全断面隧道掘进机(TBM)滚刀的破岩过程及破岩模式,分析了围压对岩体可掘性的影响。得到:(1)围压的存在抑制中央裂纹的扩展;(2)随着围压的增加,赫兹裂纹的扩展方向发生偏转,与水平面的夹角变小;(3)相同贯入度下,随着围压的增加,滚刀法向力及其掘进指数均增加。利用GPD法分析了锦屏二级水电站隧道施工中,含节理的岩层中高地应力对TBM滚刀破岩的影响,成功模拟出高地应力下节理岩体的板裂化现象,得到高地应力能够使岩体产生板裂化促进滚刀破岩。A novel meshless numerical method known as general particle dynamics(GPD) is used to study the effects of confining stresses on rock fragmentation by TBM cutters. The processes and modes of rock fragmentation and the diggability by TBM cutters under confining pressures of 0, 5, 10, 15 and 20 MPa are studied. The following results are obtained:(1) The confining stress is adverse to the propagation of the central cracks during the process of rock fragmentation.(2) With the increasing confining stress, the propagation direction of the Hertz cracks between two cutters changes, and the angle of cracks decreases.(3) Under the same penetration, the crack initiation forces and the diggability index significantly increase with the increasing confining stress. Moreover, the GPD method is introduced to the tunnels in the Jinping Ⅱ Hydropower Station, and the influcnces of high geostress on rock fragmentation are analyzed and plate cracking is discovered. The analysis results show that if the plate cracking is caused by high geostress, the geostress promotes the rock fragmentation by TBM cutters.

关 键 词：广义粒子动力学 围压 破岩 板裂化 TBM 

分 类 号：TU453[建筑科学—岩土工程]