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Abstract The surrounding rock of roadway in Tertiary thick coal seam in Qingshui coal mine of Shenyang is soft with high ground pressure. The tunnel had large deformation with 4 times reinforcement and much damaged support after excavation. The mechanisms of rock plastic flow，asymmetry deformation and failure and inharmonic deformation between support and rock are analyzed. The initial support with constant resistance and large deformation bolt can protect the support capacity of the anchorage zone. After the release of deformation energy by the extensional deformation of the constant resistance and large deformation bolt，the concentration stress is transferred to deep to utilize the strength of deep surrounding rock；then the stable loading plastic zone is formed. According to the characteristic of the mining roadway，the reinforced support is complementary with the strengthened roof，released stress sidewalls and supported side corner. The stability is dependent on the common load by support and surrounding rock. The new design containing anchor cable，constant resistance and large deformation bolt，steel band，injected pile is applied to successfully controlling the roadway at #205 working face in second mining area in southern mine. The theory is applied to controlling the stability of this kind of coal entry. The roof subsidence，sidewall shrinkage and floor heave reduced by 75%，60%，42%，respectively. The practice shows that the proposed method can control the deformation of the roadway with soft rock.
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Received: 24 February 2011
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2011, Vol. 30 
