Theoretical analysis on pressure arc applicable for soft rock roadway in deep mine based on bingham rheological model

摘要

The theoretical analysis on pressure arc for deep mine is conducted applying the concrete support with high strength and based on Bingham rheological model to deduce the mathematical expression between ultimate bearing capacity of pressure arc and ultimate rheological radius, to further analyze influence of residual strength for surrounding rock on ultimate bearing capacity of pressure arc and influence of tunnel radius and ground stress on rheological radius, and to take 590 transport roadway of Huaibei Luling Mine as an practical example to test the theoretical analysis.The results indicate that the ground stress and tunnel radius obviously affect the rheological radius, meanwhile, the ground stress and rheological radius have a positive correlation with radius of plastic rheological district;the grouting for surrounding tunnel rock has obviously improved the self-bearing capacity of surrounding rock and enhanced the ultimate bearing capacity of the pressure are;the calculated ultimate bearing capacity of pressure arc under the theoretical formula is 5.69 MPa, and the pressure arc has higher bearing capacity which is beneficial to restrain deformation of surrounding rock and maintains stability of surrounding tunnel rock;the numerical calculation and actual site data indicate validity of the theoretical model.