Theoretical analysis of equivalent hydrostatic stress attenuation in surrounding rocks after excavation

• DOI: 10.1007/s12517-020-05528-y
• Publication Date: 2020-06-16T04:06:12Z
• Authors: Yidan Sun; Yu Yang; Mengze Yang; Jinchan He
• Keywords: 01 natural sciences; 0105 earth and related environmental sciences

Energy concentration and redistribution are always accompanied by tunnel deformation and failure. This study uses a plain-strain model of circular openings under high in situ stress to derive the energy of the surrounding rocks before and after excavation based on elasticity. The study focuses on determining the areal extent of the surrounding rock significantly affected by the excavation. The relationship between dimensionless zonal radius ri/a and dimensionless stress σ0/R0 is determined based on two principles: (1) energy conservation and (2) the logarithmic relationship between consumed energy and the scale of fragmentation. The law of attenuation of stress in surrounding rock during the process of zonal fracture is theoretically explained. Preliminary values for the unknown parameters in the given formula are proposed using the data available, and the stress attenuation law corresponding to the given tunnels is presented.