边坡下民采空区稳定性分析及治理方案

Stability Analysis and Disposal Scheme of Non-regular Goaf under the Mine Slope

以某露天矿山边坡下民采空区为例,建立数值分析模型开展了采空区稳定性分析。研究结果表明:沿着采空区走向呈现"中间变形大,两端变形小"的位移变化现象,顶板最大下沉变形量达7.13 mm,而底板最大底鼓量为5.96 mm;跨度和暴露面积较大的采空区中间区域发生失稳垮塌的风险较大。为此,提出采用"采空区顶板崩落+边坡削坡"的综合治理方案,形成+125 m和+140 m 2个安全台阶,与初步设计终了台阶实现较好衔接;经计算,治理后的边坡安全系数达到1.26,可以避免边坡失稳滑坡事故,彻底消除采空区安全隐患。最后提出了采空区治理主要施工安全措施。

Taking the non-regular goaf under slope of an open-pit mine as a case,a numerical analysis model was established to analyze the stability of goaf. The results showed that： along the goaf,there presents the displacement with＂large deformation at intermediate and small deformation at both ends ＂. The maximum roof deformation reaches 7.13 mm,while the maximum floor heave is 5.96 mm. The middle areas of goaf with large spans and large exposed areas are at greater risk of collapse. Therefore,the comprehensive disposal plan of＂roof caving and slope cutting of goaf ＂was proposed to form two safety steps of ＋125 m and ＋140 m,which are in better connection with the final benches in preliminary design. In calculation,the slope safety factor reaches 1.26 after goaf disposal,which can avoid the landslide accident and completely eliminate the safety hazards of goaf. Finally,the main safety measures in construction of the goaf treatment were put forward.