The room-pillar goafs in the central and western China have the remarkable characteristics of multi-layer staggered and continuous distribution. And the goafs disaster has been the key issues that enterprises urgently need to solve. This paper introduces the Analytic Hierarchy Process (AHP) risk assessment method, divides the instability of the room-pillar goafs in Yushenfu mining area into three levels: mining conditions, geological conditions and goafs conditions, and analyzes such influencing factors of the instability of the goafs as the coal pillar strength, mining and retention ratio, coal pillar shape, mining times, roof control methods and collapse conditions, average stress of overlying strata, uniaxial compressive strength of overlying strata, depth of coal seam, area of goafs, surface subsidence, remaining time of the goafs, goafs instability events, etc. The weights of the first and second criterion-level factors and index-level factors of the instability risk evaluation of the coal mine goafs are obtained based on 12 influencing factors. Due to the difference of factors, the risk of the goafs is divided into four levels: safer, safer, general dangerous, and dangerous. Case analysis shows that it is feasible and reliable to evaluate the instability of room-pillar goafs using the AHP risk assessment method.
The large-area suspended roof instability disaster in the room-pillar goafs is the main hazard faced in the comprehensive control of the coal mining subsidence area in the Yushenfu mining area in China. The collapse and induced by the sudden instability of the suspended roof in the continuous room and pillar goaf mine earthquakes have become a key issue that the local governments and energy companies urgently need to solve. Based on a case of suspended roof grouting control in a section of the room-pillar goaf from Baofu Highway, the paper examines the effect of grouting control based on numerical simulation and field measurement technology. Research shows that surface surveys, undermine surveys and drilling surveys are important means and methods for judging the degree of large-area suspended roof instability in room-pillar goafs; the grouting control method is an effective method to prevent large-area suspended roof instability in room -pillar goafs disasters, and the grout stone body test technology is a necessary technique for grouting effect test. The strength of the test block in the 28-day compressive strength test of the grout test block is greater than 0.5 Mpa can satisfy the supporting effect on the roof of the room-pillar goaf area; the numerical simulation test can simulate the comparison of displacement and stress changes before and after grouting, and then provide a supporting method for the test of the grouting control effect. Comprehensive grout stone test technology and numerical simulation test technology can provide a criterion for the test of the grouting control effect of large-area suspended roof instability disasters in the room and pillar goaf, which has a certain degree of applicability and feasibility.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.