鲁地铁矿矿岩体解理裂隙发育,胶结程度差,岩体破碎,属于极不稳定矿体,开采过程中经常出现冒顶、片帮现象,开采效率低。针对该矿山这些不利情况,通过现场勘察、室内试验及数值模拟等手段,对鲁地铁矿工程地质条件及开采技术条件进行了详细研究,并有针对性提出了“采用半光爆掘进技术控制巷道成型,超前长锚杆主动支护控制顶板,纤维混凝土喷浆支护控制进路围岩,同时采用上向进路充填不接顶技术”的新方案。新设计方案在鲁地铁矿190m分段2073和2074采场进行了现场试验,每个分段垂直高度上由3次接顶充填变为1次接顶充填,每个分段减少了2次接顶充填的工作,施工难度大大降低,施工工序得到简化,安全性好,采矿效率提高了50%,取得了良好的技术经济效果。
Ludi Iron Mine belongs to the extremely unstable ore-body because of its fractured joints, poor coherence, and crushed rocks. The roof caving and side-fall phenomenon often happen in mining process with low production efficiency. In view of these unfavorable circumstances, the engineering geological conditions and mining technical conditions are investigated in detail through on-site investigation, laboratory tests and numerical simulation. A new proposal of "a half-light blast tunneling controlling the roadway ,long advanced bolts actively supporting the roof, fiber reinforced shotcrete supporting the surrounding rocks at route, and the upward drift backfill mining with roof unconnected" is put forward. It has been applied in field test at 2073 and 2074 working faces of 190 m sublevel in Ludi Iron Mine. Roof-contacted filling was dropped from 3 times to 1 in one sublevel vertical height, and 2 times of backfilling was reduced at each stage. It simplifies the construction process and makes the production safer. The new proposal significantly improves the mining efficiency by 50% with good technical and economic benefits achieved.