In order to solve the large deformation problems of the deep gob-side entry driving at No.15 coal seam in Yangquan Mining Area,its geological characteristics,geological mechanical parameters characteristics and original supporting design were analyzed,which revealed the laws of deep roadway deformation,relatively stable initially,roof by the rib bends and subsides subsequently,large inverted trapezoid deformation,roof destabilizes.It pointed out that the high in situ stress,big principal stress difference,and multiple mining were the fundamental factors which affected the stability of the roadway,and low strength of initial support of and weak side support were the deciding factors.Combination with analysis of relation between coal pillar size and stress of surrounding rock,the high pre-stress control technology was put forward,which was lay its focus on supporting the strong coal side with auxiliary support between roof and coal side.The results showed that the initial support intensity increased by 149％ and sectional convergence rate decreased by 48％.The technology ensured the roadway stability,and met production requirements.%为解决阳泉矿区深部开采15号煤层沿空掘巷围岩变形量大的问题,分析了其工程地质特点、地质力学参数特征及原支护方案,揭示了深部沿空掘巷初期相对稳定—靠帮顶板弯曲下沉—倒梯形大变形—顶板失稳的变形规律,研究了巷道变形破坏机理,指出原岩应力高、主应力差大、多次采动是影响巷道稳定的基础因素,初期支护强度低和弱帮支护是决定性因素.结合煤柱尺寸与围岩应力关系分析,提出了以强帮支护为主、项帮协调支护的高预应力控制技术.结果表明:初期支护强度提高了149％,断面收敛率降低48％,保证了巷道整体稳定,满足安全生产要求.
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