摘要
为揭示高轴向水平压力作用下洞室围岩变形与破坏规律,研究了模型介质断裂形态,指出模型裂缝存在剪切和拉伸两种形式;采用锯齿形岩石模型和极限应变破坏准则,推导了洞室围岩的应力场,定量分析了试验结果;通过与试验对比,证明了解析的正确性。研究表明,在高轴向水平压力作用下,洞周介质会产生间隔的拉伸裂缝,形成分层断裂现象。拉伸裂缝的几何形状逐渐趋于圆形,每形成一道拉伸断裂,模型等效于形成一个受支护作用的洞室,随着等效洞室半径的增大,其受到的支护力迅速增大,使得分层断裂现象局限在一定范围内。可为深部防护工程设计提供参考。
Under high axial direction horizon pressure,the medium of tunnel model presents multi-layered failure.The fracture shape of enclosing rock mass were studied and the failure of the model medium was proved to be in the patterns of tension and shear.By the hackly rock mass model and the ultimate strain failure criteria,the stress field of the enclosing rock mass was deduced.Contrasted with the test result,the solution was proved to be correct.The analytical result shows that the tension fracture will repeatedly occur under high axial compression stress,causing layered failure,that the geometry of tension fracture goes to roundness gradually,that when a new tension fracture is taking shape,the model is equal to a new tunnel with supporting,and that with the increment of the tunnel radial,the supporting force grows rapidly,which makes the layered failure localized in a certain range.The analytic method can offer valuable reference to protective engineering design in deep.
出处
《解放军理工大学学报（自然科学版）》
EI
北大核心
2010年第6期652-657,共6页
Journal of PLA University of Science and Technology(Natural Science Edition)
基金
国家自然科学基金重大资助项目(50490270)
国家创新研究群体科学基金资助项目(51021001)
国家杰出青年基金资助项目(50825403)
关键词
岩石力学
深部巷道围岩
分层断裂
破坏机理
rock mechanics
enclosing rock mass around deep tunnel
multi-layered failure
mechanism of failure
