Study On Construction Mechanics Of The Unsymmetrically Loading Tunnel In Geological Bedding Strata

In mountain tunnel building process, sometimes the tunnel will cross the slant layered rock mass, Because slant layered rock mass have different mechanics characteristics along bedding plane direction and the perpendicular bedding plane direction, This type of rock mass can not be thinked as the isotropic rock mass, in order to decide the mechanics characteristics of the excavating in the layered rock mass, the behavior of mechanics of lining structure excavating in this type of rock mass is analyzed in the way of theory analysis, numerical simulation and model test.This dissertation first analyzed the contributing factors, distinguishing methods and study status of the unsymmetrical loading tunnel. And the calculation methods of the pressure of surrounding rock masses is discussed in this thesis.Indoors model test employing similarity materials and mainly considering V-class surrounding rock is carried out in respect of single track , the characteristics of stress distribution for the ling structure in bedding stratified rock mass is studied in the thesis.This dissertation is based on the characteristic of Anisotropic rock masses, transversely isotropic rocks is hypothesized, Deduced the stress characteristic of surrounding rock inside transversely isotropic rock masses, disaster character of tunnel excavating in the type of transversely isotropic rocks is analyzed, the surrounding rock steadiness control strategy is put forward, it will provide theory reference and preventing technique for the tunnel deformation and collapse etc.The numerical simulation is proceeded to the behavior of mechanics excavating in the layered rock mass with the general FEM software ANSYS, for exploring the reasonable lining structure form in the geological unsymmetrically loading tunnel, symmetrical and unsymmetrical lining structure stress distribution characteristic is also analyzed in this thesis.Finally, this thesis combines Yutangwan single track tunnel expatiated construction technique in the geological unsymmetrically loading tunnel, it will have certain reference value for similarity engineering design and construction inthe future.