随着开采深度的进一步增加,贵州开磷集团马路坪矿区深部主要开拓及采准巷道支护困难,原有的支护技术与措施失效,巷道返修率高,永久性巷道支护后存在经常性冒顶、片帮、底鼓等现象。针对开磷集团马路坪矿区深部红页岩巷道围岩严重破坏问题,通过现场调查和理论分析,提出加固底板控制巷道底鼓的措施,在原支护方案的基础上设计了3种改进方案。使用离散元软件3DEC对上述原方案及其改进方案分别进行了数值模拟计算,同时选取了100m试验巷道进行现场试验。模拟结果表明,底角锚杆可以切断底板基角部位塑性滑移线从而控制巷道底鼓,浇灌混凝土地坪并铺设钢筋网,能增强底板的韧性,保证底板围岩的整体性,可以大大提高底板围岩抵抗岩块碎胀压力的能力,防止底板围岩开裂挤出。现场测试数据显示联合支护方案减小底鼓量83%,较好控制了巷道底鼓灾害,解决了长期困扰开磷矿山红页岩巷道的支护难题。

With the increase of depth in mining engineering, many support difficulties occurred in main development and preparation roadways in Maluping mining area of Guizhou Kailin Group. Traditional support technologies and measures failed to work. Problems in terms of the safety of the permanent roadways such as roof falling, rib spalling and floor heaving were often found, to require repetitive rebuilding work. To control and prevent the severe destruction of the surrounding rocks in the deep red shale roadway of Maluping mining area, in-situ investigations and theoretical analysis were carried out and an approach was put forward to control the floor heave by strengthening the floor. Meanwhile, three new improved support schemes were adopted on the basis of the original support scheme. The original scheme and these three improved schemes were simulated by using 3DEC, a discrete element code, and then in-situ tests were performed in a 100m long experimental roadway. Simulation results indicate that floor anchors can be used to control the floor heave by cutting the plastic sliding line located in floor corners. An improvement of floor toughness, integrity and bearing ability against the bulking pressure of rocks was achieved by placing steel meshes on the concrete floor. The in-situ test data show that the combined support scheme would reduce the floor heave by 83%, which has solved the support problem in Kailin Mine, that had been affecting the mine production for a long time.