ELASTRO-PLASTRC RESEARCH OF SURROUNDING ROCK BASED ON HOEK-BROWN STRENGTH CRITERION

The surrounding rock zoning and analysis are the main basis to determine the roadway bolting and loose ground pressure.Displacement of surrounding rock is the main parameter for the design of coal mine tunnel cross section and the determination of distortion geostatic pressure.This paper adopts Hoek-Brown strength theory and limit equilibrium equation and carries out the elasto-plastic analysis of an idealized roadway surrounding rock with a unit lateral pressure coefficient.It derives the plastic zone radius,stress field and displacements of the surrounding rock.The results are further compared with the results determined from the widely used Fennner formula associated with the Mohr-Coulomb yield strength criterion.