金属矿山充填体强度分布规律实验研究

摘要

The first part of the second phase of Tibet Jiama polymetallic copper ore deposit is explored by filling mining method. Because of the filling slurry′s segregation and other reasons in the filling process,the in-situ filling body appears non-uniform,and its strength also has the much difference with standard backfill block in laboratory. The regularity of strength dis-tribution of the filling body in stope was studied by building a large scale three-dimensional similarity simulation experiment system. The results showed that in horizontal direction,the strength of the filling body increased and then decreased with the slurry flow direction. The filling body strength with high cement-sand ratio changed less,and the strength of the filling body near the feed outlet was equal to the strength of standard filling body. In vertical direction,the strength of the filling body in-creased with its depth,and the filling body strength with high cement-sand ratio increased greatly. The microstructure of the fill-ing body samples observed by scanning electron microscope can essentially explain the reason for the difference in the strength of the filling body.%西藏甲玛铜多金属矿二期工程首采地段采用充填采矿法进行开采.由于在充填过程中充填料浆的离析分层等原因致使形成的原位充填体具有不均匀性,其强度与实验室充填体标准试块的强度也有很大差异.通过建立大比例尺三维立体仿真物理模拟实验系统,研究采场内充填体强度的分布规律.结果表明:在水平方向上充填体强度随料浆流动方向上呈先增大后减小的趋势,高灰砂比的充填体强度波动程度较小,且在下料口位置附近充填体强度与标准充填体试块强度相当;在竖直方向上充填体强度随深度的增大而增大,且高灰砂比的充填体强度增幅较大.通过对充填体样本进行电子扫描显微镜实验观察其微观结构,从本质上解释不同位置充填体强度差异的原因.