Study on the Evolution Law and the Orientation Criterion of a Plastic Zone in Rock Surrounding a Circular Roadway in a Three-Dimensional Non-Isobaric Stress Field

Hongtao Liu,Jiquan Ma,Shengjie Wei,Zhou Han,Xiaofei Guo,Zilong Luo,Tianhong Huo,Zijun Han

doi:10.3390/app12062947

Abstract

The original rock stress field is mainly divided into the σHZ-dominant stress field, the σZ-dominant stress field, and the σH-dominant stress field. Via theoretical analysis, the plastic zone morphology and the orientation of roadway surrounding rock under a three-dimensional stress field are studied in depth, and the theory is verified by numerical simulation. The results show that in the σHZ-dominant stress field, the plastic failure mode changes from elliptical to quasi-circular to butterfly, and the optimized angle range of the roadway orientation is determined by three principal stresses. In the σZ-dominant stress field, the shape of the plastic zone transforms from butterfly to ellipse, the optimized angle range of the roadway orientation is 50–90°, and the butterfly hidden danger zone is in the 0–50° range. In the σH-dominated stress field, the shape of the plastic zone transits from ellipse to butterfly. The optimized angle range of the roadway orientation is 0–40°, and 50–90° is the butterfly hidden danger zone.

Highlights

Ground stress is the main factor leading to the failure of roadway surrounding rock, and the original rock stress field is the basis for analyzing the stress redistribution of roadway surrounding rock
Bagheri et al deduced the boundary equation of the plastic zone of the surrounding rock of a circular roadway and established a two-dimensional numerical simulation model
Based on the butterfly failure theory of roadway surrounding rock, this paper studied the evolution law and orientation criterion of the plastic zone in rock surrounding a circular roadway under different stress fields, providing theoretical guidance for optimal roadway layout

Summary

Introduction

The deformation and failure of roadway surrounding rock have been hot topics of research; the control of the plastic zone expansion of roadway surrounding rock is a problem that needs to be urgently solved. It is critical to study the roadway orientation under different stress fields for the stability of roadway surrounding rock [1,2]. Bagheri et al deduced the boundary equation of the plastic zone of the surrounding rock of a circular roadway and established a two-dimensional numerical simulation model. The radius of the plastic zone was measured and analyzed by applying 13 stress states, helping to verify the theoretical analysis [8]. Xu et al put forward the pressure relief method of slotting in the roof and floor of a roadway and studied the release effect of the slotting depth on the plastic zone by the

Results

Discussion

Conclusion