Application of caving mining technology with bottom under condition of flat dipping mid-thick body and unstable rock caused the most of trench and bottom drift, located in abutment , to be destroyed and low recovery in south area, Xishimen Iron Mine.

• 摘要在缓倾斜中厚矿体底板岩性不稳固的条件下，采用有底柱崩落法，由于电耙道大多处于空区边部应力集中的部位，致使堑沟及底部结构巷道破坏严重而使回收率极低，采用无底柱崩落卸压则可有效解决上述难题。