白竹村大型山体变形特征及成因机制研究

Study on Deformation Characteristics and Formation Mechanismof Large Mountain in Baizhu Village

隧道-斜坡工程体系是极为复杂的系统,在复杂的地质环境下,隧道-斜坡工程体系相互作用既涉及公路施工和运营安全,也涉及坡体上方居民的生命财产安全。针对阿比村隧道-白竹村山体斜坡工程体系,通过地质调查、地表与深部位移综合监测、数值模拟计算等技术手段,研究了白竹村大型山体变形特征及成因机制。研究结果表明:①白竹村山体变形规模巨大,表现为隧道进口至进尺1300 m处山体向北西侧变形,变形范围长约540 m、宽约450 m,山体变形影响平均深度约130 m,总体方量约1100×10^(4)m^(3),山体变形是隧道-斜坡工程体系相互作用的结果;②山体变形的成因机制可概括为“震动开裂-突泥临空-中段牵引-向前推挤”这4个阶段;③山体变形速率在空间上存在差异性,山体中后部位移速率明显大于前部,在时间上与隧道施工存在关联,隧道施工完毕后,山体表面位移呈收敛趋势。

The tunnel-slope engineering system is a very complex system.In the complex geological environment,the interaction of tunnel-slope engineering system involves not only the safety of highway construction and operation,but also the safety of life and property of residents above the slope.Aiming at the Abicun tunnel-Baizhucun mountain slope engineering system,the article studies the deformation characteristics and formation mechanism of Baizhucun large-scale mountain through geological survey,comprehensive monitoring of surface and deep displacement,numerical simulation and other technical means.The results show that:①The deformation scale of Baizhucun mountain is huge,which is manifested as the deformation of the mountain from the tunnel entrance to the footage of 1300 m to the northwest side.The deformation range is about 540 m long and 450 m wide.The average depth of the mountain deformation is about 130 m,and the total volume is about 1100×10^(4)m^(3).The mountain deformation is the result of the interaction of the tunnel-slope engineering system.②The formation mechanism of mountain deformation can be summarized as four stages:vibration cracking-mud bursting-middle traction-forward pushing③The deformation rate of the mountain is different in space.The displacement rate of the middle and rear part of the mountain is obviously larger than that of the front part,which is related to the tunnel construction in time.