为深入分析徐楼铁矿地表沉降成因,预测矿区地面沉降规律,首先分析了该矿一期采矿工程地面沉降的发育现状,然后从围岩应力场、矿体赋存条件、矿区地下水疏排、区域地质构造、采空区充填等方面对矿区地面沉降成因进行了讨论,最后基于矿区现有的工程地质资料及地面沉降监测资料,采用概率积分法和曲线拟合法预测了矿区地面沉降范围及沉降量,并对预测结果进行了分析。结果表明:1该矿区地面沉降是围岩应力场、矿体赋存条件、矿区地下水疏排、区域地质构造、采空区充填等因素共同作用的结果;2概率积分法预测的采空沉陷区面积约0.22km2,矿区主井、副井、风井及采矿工业场地大部分位于预测采空塌陷区内,可能引发的采空区塌陷灾害危险性较大;3曲线拟合结果与实测数据较吻合,可较好地反映矿区沉降的实际情况,精度较高。上述结果进一步表明:近年来,矿区地面沉降量和沉降范围呈剧烈加速的趋势,实测沉降影响范围及沉降量远小于预测结果,可见地表仍有一部分建(构)筑物及设施位于预测沉降范围内,此外,随着二期采矿工程的全面展开,矿区地面沉降量及沉降范围在短期内仍会继续增大。
In order to further analyze the subsidence causes and predict the rule of the surface subsidence in the Xulou iron mine,firstly,the development status of surface subsidence status of the first phase mining project of Xulou iron mine are introduced;then the subsidence causes of Xulou iron mine are discussed in depth from the five aspects of surrounding rock stress field variation,ore-bodies occurrence conditions,groundwater drainage in mining area,regional geological structure and the goaf filling;finally,base on the existing engineering geological data and subsidence monitoring data,the probability integral method and curve fitting method are adopted to predict the surface subsidence range and settlement in the mining area,the prediction results are analyzed in detail. The results show that:1 the surface subsidence of the mining area is jointly resulted from the factors of surrounding rock stress field variation,ore-bodies occurrence conditions,groundwater drainage in mining area,regional geological structure and the goaf filling;2 the subsidence area predicted by the probability integral method is about 0. 22 km2,the main shaft,auxiliary shaft,air shaft and the most of the mining industry field are lied in the predicted mining subsidence area,it is more likely to cause the goaf subsidence disaster with great danger;3 the curve fitting results with high accuracy and good effect that is comparatively in agreement with the actual measured data,that is to say,the curve fitting results can well reflect the actual surface subsidence situation of the mining area. The above analysis result further show that the surface subsidence range and settlement of the mining area with the trend of violently accelerating,the actual measured surface subsidence range and settlement are much smaller than the prediction results which indicated that a part of surface buildings or constructions and facilities are located in the prediction area,in addition,with the comprehensive development of the second mining stage project,the surface