土石混合体渗透性现场试坑试验研究

针对唐钢司家营铁矿Ⅲ采场露天转井下开采回填废石设计研究工程要求，在该矿区Ⅲ采场附近进行了大尺度现场渗透试验。开挖3个大尺寸试坑，在各试坑中分层回填不同粒径范围及厚度的废石（土）进行试坑注水试验；测定回填土石混合体的近似渗透系数，测试土石混合体的粒径组成，并计算出各坑土石混合体的平均粒径和非均匀度。试验研究发现，回填土石混合体的渗透系数分别随平均粒径与非均匀度的增大而增大。降低回填废石（土）的平均粒径和非均匀度可以有效降低回填废石层的渗透性。

In-situ experimental study of permeability of rock and soil aggregates

In order to meet the engineering requirements of the design of backfilling waste rock, which will be implemented during surface mining to underground in the pit III of Sijiaying iron mine, a large size in-situ permeability test in the test-pit near the pit III is performed. Digging three large size test-pits, an injection test is performed in each test-pit with different ranges of particle sizes and layer thicknesses. The permeability coefficients are measured, the size composition of rock and soil aggregates(RSA) is tested; and the mean particle diameter and the heterogeneous degree are figured out. Through the research, the permeability coefficient of RSA increases with the increase of mean particle diameter and the heterogeneous degree respectively. Accordingly, decreasing mean particle diameter and heterogeneous degree can decrease permeability of waste rock effectively.