露天与地下联合开采引起岩层移动规律的模型试验研究

;非法开采对矿山开采稳定性具有重要影响,以某铁矿为例,进行了二维物理相似模型试验研究,分析得出了在考虑和不考虑非法开采两种情况下的地表变形规律和矿体围岩移动规律.试验结果表明,从-270 m采至-550 m水平期间,地表沉降和围岩变形呈缓慢增加趋势,但当从-550 m水平继续向下开采时,由于矿体倾角变得平缓,地表沉降、深部围岩变形都急剧增加,非法开采会造成矿体上部岩体的应力重分布,虽没有明显增大地表的沉降范围,但增加了开采点附近的地表沉降量,而且大大增大了地表岩层的水平移动.

Model test study on rock movement caused by open-underground combined mining

Illegal mining has a great influence on stability of mines. Based on the prototype of the representative metal mine, two-dimensional physical simulation model test on an underground iron mine is carried out. The regulations of surface deformation and surrounding rock movement with or without illegal mining are obtained respectively. Results obtained indicate that when ore between –270 m and –550 m are excavated, the subsidence of surface and deformation of surrounding rock increase slowly. But when ore below –550 m are excavated, the subsidence of surface and deformation of surrounding rock increase quickly because the obliquity of orebody become smaller. Because of stress redistribution caused by illegal mining, the size of surface subsidence increases near surface gob and horizontal displacement of surface increases greatly; but the range of surface subsidence almost has no change.