采空区顶板破坏机理研究及安全厚度确定

采空区是造成我国矿山灾害事故的重要原因，其顶板安全厚度的确定是一直未能得到很好解决的难题。首先基于薄板理论提出采空区顶板厚度计算新方法，揭示空区顶板安全厚度与顶板几何尺寸及矿石力学特性指标的关系。在得到理论解的基础上，从力学角度分析顶板破坏原因和过程，采用ABAQUS有限元分析软件建立采空区顶板的数值力学分析模型并进行模拟，分析采空区顶板破坏过程和各因素的影响规律。通过数值模拟对采空区顶板进行应力、应变及顶板位移的塑性分析，得到不同顶板厚度、不同采空区跨度等对应力场、位移场的影响规律和采空区顶板安全厚度与采空区跨度的回归曲线及方程。最后通过理论解与数值模拟的比较确定齐大山某空区的顶板安全厚度。

Goaf Roof Failure Mechanism and its Security Thickness

The existence of goaf is an important factor resulting in mine disaster. It is still an unresolved problem to make sure the roof safe thickness of goaf. In this paper，a new calculation method of goaf roof thickness is put forward based on thin plate theory，which reveals the relationship between the safe thickness of goaf roof，geometry size of roof and mechanical property of ore. On the basis of the theoretical solution，the reason and process of the roof damage is analyzed from the mechanical point of view. A numerical mechanical model of goaf roof is established using the finite element analysis software，ABAQUS. The failure process of goaf roof and its effect factors are considered. The stress，strain，and displacement of the goaf roof are analyzed through numerical simulation. The influence of roof thickness and goaf span on the stress and displacement field are obtained，and the regression curve and equation of the roof safe thickness and goaf span are derived. Finally，compared the theoretical solution with numerical simulation results，Qidashan roof thickness can be determined.