60°倾角正断层黏滑错动对山岭隧道影响的试验研究  

Model experimental study on influence of normal fault with 60° dip angle stick-slip dislocation on mountain tunnel

作　　者：刘学增[1] 王煦霖[2] 林亮伦[3] 

机构地区：[1]同济大学土木信息技术教育部工程研究中心,上海200092 [2]同济大学土木工程学院,上海200092 [3]重庆市建筑科学研究院,重庆400015

出　　处：《土木工程学报》2014年第2期121-128,共8页China Civil Engineering Journal

基　　金：国家自然科学基金(51278377);交通运输部科技项目(2011318775.680);上海市优秀技术带头人计划资助(12XD1424100)

摘　　要：通过1∶50室内模型试验,模拟了60°倾角正断层黏滑错动下,与之正交的隧道结构的受力变形破坏过程,并布置传感器监测了隧道顶部和底部的地层压力、隧道轴向的应变和隧道环向的应变。试验结果表明,地层的永久变形和地层-结构的相互作用,导致了围岩压力在剪切带附近发生显著变化,上盘和剪切带范围内拱顶压力显著增大,下盘拱顶压力次之,上盘和剪切带隧道底部压力减小,下盘底部压力显著增大,隧道与下部围岩可能局部脱空以适应断层的剪切位移;上盘和剪切带范围内纵向弯矩为正,下盘范围内为负,隧道偏心受压;以原型混凝土压坏来判定衬砌破坏,初步确定原型结构破坏所容许的最大断层位移D=0.3m,理论上该值略偏大;隧道衬砌破坏区域,在剪切带和下盘范围分别为0.75和1.5倍隧道宽度。The force-deformation mechanism and failure process under the effects of stick-slip dislocation of the normal fault with 60°obliquity is studied by a 1 ： 50 model experiment. The strata pressure of the tunnel vault and bottom, axial strain and hoop strain were monitored. The result show that with the normal fault rupture propagating in the overburden layer, the tunnel structure orthogonal to the normal fault emerge relatively big shear displacement. The strata permanent deformation and the interaction between the strata and the tunnel structure cause the formation pressure changes significantly. The pressure on the vault in the hanging wall and the shear zone increases significantly, followed by the pressure on the vault in the foot wall. The pressure on the tunnel bottom in the hanging wall and the shear zone decreases, while the pressure in the foot wall increases. The tunnel may possibly separate from the wall rock to accommodate the shear displacement of the fault. The longitudinal bending moment is positive in the hanging wall and the shear zone and negative in the foot wall zone due to the eccentric pressure in tunnel. By evaluating the lining failure from the cement prototype under compression, the maximum allowed fault displacement of the prototype structure is determined as D = 0.3m, which is overestimated in theory. Tunnel lining fracture length is 0.75 and 1.5 times the width of the tunnel in the shear zone and foot wall zone respectively.

关 键 词：正断层 公路隧道 黏滑错动 模型试验 

分 类 号：U45[建筑科学—桥梁与隧道工程]