Surrounding Rock Mechanical Analysis Of Underground Non-circular Opening With Full Support

In order to achieve effective utilization and development of undergroundspace, people often need excavate underground opening with differentcross-sectional shapes and sizes in rock mass. The excavation will destroy theinitial equilibrium state of the rock mass, which will affect the security andstability of rock caverns. For the opening without support or circular openingwith support, some literature has given the corresponding analytical solution,and the related theory has been relatively mature. However, for the non-circularopening with support, most articles adopt the method of experimental test or thefinite element numerical analysis, but the theoretical solutions are relativelyrare.In this thesis, based on the theory of complex variable function, themechanical analysis of surrounding rock opening is classified as the problem ofan infinite body with hole. By using the method of conformal mapping, thecomplex support section will be transformed to a ring area which boundaryshape is simple. In the process of transformation，optimization methods areadopted, to find a suitable mapping function and make the mappingfunction satisfy the coincidence conditions of the inner and outer boundaries ofthe support. Subsequently, the series solutions of the stress and strain ofsurrounding rock and support is derived，and the results are proved by the finiteelement analysis. Finally, the variations of the stresses and strains in the supportand the surrounding rock are discussed with different rock mass classifications,depths of the opening and lateral pressure coefficients.