Experimental Study Of Supporting Technique In Deep-Seated High Stressed Soft Rock Roadway

Supporting technique in deep-seated high stressed soft rock roadway is always one of the puzzles in underground engineering field at home and abroad. With increasing of exploit depth, complexity of environment, burst casualty and heavy accidents are more frequent, work environment is more formidable, cost of production is rising rapidly, which challenge the supporting engineering in the deep-seated resource exploit. Therefore, it is very important and meaningful to study proper supporting technique in deep-seated high stressed soft rock roadway.This paper mainly studied the existed problem in chamber and roadway of shaft station in Tangkou mine, which is deeper than one thousand meters and through mineral component analysis and physical property test, ground stress test, similar simulation experiment and so on to design proper supporting structure and parameters. With grouting-bolting as the kernel, pre-stressed anchor rope truss as the assistant, the combined supporting system solved the supporting problem in deep-seated high stressed soft rock roadway. This paper generalized the surrounding rock deformation property, analyzed the load-bearing mechanism of the grouting-bolting supporting structure, the pre-stressed anchor rope and the anchor rope truss. According to the elastic-plastic character of the grouting-bolting structure, the expanding law of its elastic-plastic zone was disclosed through the elastic-plastic theory, the calculating equation of its ultimate bearing capacity was put forward. This paper discussed engineering classify of the soft rock roadway, and analyzed the Tangkou mine soft rock roadway through this classify standard.This paper used the finite-difference program FLAC3D to simulate supporting methods in the pump room, including excavation in pump room without supporting, the rheologic change after excavation, supporting without anchor rope truss and supporting with anchor rope truss, and compared the supporting effect on stress, deformation, plastic zone development and so on in the surrounding rock, proved the effect of anchor rope truss on keeping the surrounding rock steady, at last simulated the combined supporting method of grouting-bolting with equivalent method.