Study And Practice On Comprehensive Supporting Technology Of High Stress In Soft Rock Roadway In Thousands Of Meters Depth

Pressure control of soft rock roadway in deep mine has always been one of the difficult problemsin mine engineering. With the rapid development of the society, the increasingly urgent need formining resources requires us to expand the exploiting scale, as well as the depth. Nonetheless, theissue of supporting and maintaining of soft rock roadway in deep mine has being becoming more andmore protruding, because of the high ground-stress and various influential factors in deep mine. Hence,the fact whether the issue can be successfully resolved or not directly determines the deeperexploitation and safer production. Moreover, the underground workers life safety will be at risk; theproduction and economic benefits will also be damaged.This paper directs at the distortion and damage of roadways in deep soft rocks of XuzhouPangzhuang Coal Mine while digging and using. Combined experience of construction withinvestigation and survey on spot, this paper analyses the reasons and regulations of distortion anddamage, adopting a method of theory analytical and numerical simulation. In addition, pressurecontrol methods are put forward in this paper. In test zones of Xuzhou Pangzhuang Coal Mine, tosome extent, reasonable and feasible maintenance methods have instructive meanings for controllingroadway pressure based on different conditions of rock and stress as well as experimental research.The main findings are listed as follows:(1) Geological radar (RAMAC/GRP), which is made in Sweden, is employed to measure theconvergent deformation and the degree of damage of the roadway and the loose circle of the damagedsection of wall and arch. Though analyzing, we draw a conclusion that the deformation of the belttransportation roadway is very serious at-1010m of Zhang Xiaolou Colliery, and the range of theloose circle of the roadway is up to above2.6m, which belongs to large broken zone. Therefore, thesupporting mechanism of the belt roadway cannot effectively control the deformation of thesurrounding rock at-1010m of Zhang Xiaolou Colliery.(2) We make numerical simulation analysis to the two different supporting methods of steel archand anchor net spray at-1010m belt roadway of Zhang Xiaolou Colliery with the aid of ANSYSsoftware, and get the control effect of the surrounding rock and stress field distribution by differentsupporting methods in the same stress condition. Thus, we conclude the reason of the distortion of theroadway that the supporting methods of steel arch and anchor net spray can receive good supporteffect in normal geological conditions. However, in complex geological conditions, such as faultfracture zone, fold, etc., the support effect is not good enough. Hence, the method of the totallyenclosed bolt-grouting support is put forward.(3) Through the numerical simulation analysis of the totally enclosed bolt-grouting support withthe aid of ANSYS software, we make the field observation and analysis and get to know that the totally enclosed bolt-grouting support can effectively control the deformation of the soft rock roadwayat great depth under the complex stress condition.(4) From the economic perspective, the practice of successful totally enclosed bolt-groutingsupport can achieve better benefit, and can be widely popularized and applied.