软介质接顶沿空留巷充填体稳定性研究

Study on stability of filling body of soft-stayed top-down gob-side entry retaining

为了减少沿空留巷巷道的变形量,保证上覆岩层不发生大的离层,避免直接顶的严重破坏,采用理论分析与FLAC3D数值模拟相结合的方法,研究了软介质充填体的力学特性、结构特性与沿空留巷围岩稳定性关系,数值模拟分析了软介质接顶充填体的巷道围岩应力分布与位移分布,研究得出:矸石混凝土在强度上满足沿空留巷支护的要求;随着工作面的开采,实体煤一侧形成应力增高区,垂直应力峰值为17.06 MPa;对混凝土墙体进行应力检测,得到混凝土墙体垂直应力为3.0 MPa,水平应力为2.0 MPa;由数值模拟与现场实测分析知,工作面回采结束后,巷道变形量较小,能有效起到充填支护及切顶作用,巷道围岩整体稳定性较好,研究为沿空留巷充填体稳定性提供一定的技术支持。

In order to reduce the deformation of roadway along gob side entry,and to ensure that the overburden was not separated from the overlying strata,and the serious damage to the roof was avoided. The mechanics of the soft medium filling body was studied by combining the theoretical analysis with FLAC3 Dnumerical simulation software. The relationship between structural characteristics and the surrounding rock stability of the roadway along the gob,and the numerical analysis of the stress distribution and displacement distribution of the surrounding rock of the soft medium connected with the soft medium was carried out. The vertical stress of the concrete wall was 17. 06 MPa,and the stress of concrete wall was tested,and the vertical stress of concrete wall was 3. 0 MPa,and the horizontal stress was 2. 0 MPa. From the numerical simulation and the field measurement analysis： the roadway from the overall situation,after the end of the mining face,the deformation was small,can effectively play the role of support and cutting roof,roadway surrounding rock stability well,and the research provided some technical support for stability of roadway alonggob side entry.