Abstract
Providing support for deep soft rock roadways under dynamic pressure is a major technical challenge. In this study, the distribution characteristics of surrounding rock-bearing structure of such roadways were systematically examined using theoretical analysis and numerical simulation. Based on the control effect of different support methods on the surrounding rock-bearing structure; a reinforcement scheme for deep dynamic soft rock roadway was proposed and applied. The results indicate that: (1) by increasing the supporting strength of the internal bearing structure, cohesion, and internal friction angle of the surrounding rock, and by reducing the influence of mining, making the external bearing structure close to the roadway and reducing the thickness of the bearing structure, can improve the bearing capacity of the shallow surrounding rock in the roadway; (2) under the conditions of dynamic load and creep of the surrounding rock; the deformation of the rock increases significantly; external bearing structure is far away from the roadway, and thickness of the bearing structure increases; anchor cable support and floor pressure relief effect better control over the roof and the roadside deformation and floor heave, respectively; and the thickness of the corresponding external bearing structure is reduced by 30.84% and 41.50%, respectively; and (3) based on the application, the zonal reinforcement scheme of “fix cable to shed, floor pressure relief, deep-shallow composite grouting” is proposed and put into practice, with good results. The results of this study can provide theoretical support and reference for the determination of supporting parameters in deep roadways.
Highlights
As the depth of coal mining increases year by year, the difficulty of ensuring the stability of rocks that surround roadways in the face of complex geological conditions and mechanical environment poses a serious challenge to the safe and efficient mining of deep coal resources [1]
In view of the high ground pressure, considerable disturbances, and plastic softening of rock mass in the deep roadway, several studies have been conducted on the control of surrounding rock in deep roadways focusing on three main areas: change characteristics of brittleness to ductility of deep rock mass, bearing mechanism of the rock, and the control technology used
It was found that there were extruding and compressive zones in surrounding rock, and the compressive zone increased the stability of the surrounding rock; Kang [12] put forward the key circle theory of rocks surrounding roadways, and expounded the influencing factors of the key bearing circle and its distribution characteristics; Zhang et al [13] studied the bearing mechanism of double bearing structures in deep soft rock roadways; considering the rock surrounding a broken roadway as a small bearing structure and the deep surrounding rock as a large bearing structure, Yang et al [14] proposed the superimposed coupling support technology for large and small bearing structures; Wang et al [15] and Yang et al [16] analyzed the bearing mechanism of rock surrounding roadways from the stress distribution
Summary
As the depth of coal mining increases year by year, the difficulty of ensuring the stability of rocks that surround roadways in the face of complex geological conditions and mechanical environment poses a serious challenge to the safe and efficient mining of deep coal resources [1]. Based on the analysis of the plastic zone theory, Zhang et al [8] considered that the range and shape of the plastic zone of the surrounding rock is the theoretical basis for the quantitative design of the supporting structure, and proposed a support scheme for the weakly cemented soft rock roadway; Zhang et al [9] studied the distribution characteristics of surrounding rock loose circle in weak roadway, and guided the design of the supporting parameters; Zhu et al [10] studied the coordination effect of the primary and secondary bearing areas of the surrounding rock, and concluded that the surrounding rock compression domain is the main bearing area; Nazimko et al [11] studied the failure process of the surrounding rock in roadways under deep dynamic pressure by actual measurement. The results can provide references for surrounding rock control in deep dynamic soft rock roadways
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
