论文部分内容阅读
为解决清水营矿+786 m水平临时水仓大断面软岩巷道变形严重难以控制的支护难题,现场考察了巷道变形破坏形态,取样测试了巷道围岩物理力学参数,分析了巷道变形破坏原因。研究得出:临时水仓巷道围岩属于典型的强膨胀型极软弱岩层,其变形主要由黏土矿物的滑移与吸水膨胀引起。基于上述研究,提出了“锚网喷+立椭圆形钢管混凝土支架+钢纤维混凝土碹体+加固锚索”的封闭式复合支护方案,建立了基于钢管混凝土支架的软岩巷道承压环强化支护力学模型,计算得出承压环的极限支护阻力可达1.99 MPa。随后运用FLAC~(3D)软件对不同断面形状的复合支护效果进行了对比分析,验证了设计方案的合理性。最后,该复合支护技术在井下获得了成功应用,工程应用表明:巷道支护3年多来,围岩最终变形量小于100 mm,并且支护体力学性能良好,有效地控制了大断面软岩巷道的收敛变形。
In order to solve the problem of serious and difficult control of soft rock roadway with large cross-section in temporary watercourse at +786 m level in Qingshui, the deformation and failure modes of the roadway were investigated on site. The physical and mechanical parameters of the surrounding rock were sampled and analyzed, . The study shows that the surrounding rock of the temporary waterway is a typical strong inflatable extremely weak rock formation, and its deformation is mainly caused by the slip and water swelling of clay minerals. Based on the above research, a closed composite support scheme of “anchor net spraying + vertical elliptical CFST bracket + steel fiber reinforced concrete body + reinforcing anchor cable” was proposed, and the bearing capacity of soft rock tunnel based on concrete filled steel tube Ring reinforced support mechanical model, calculated support ring pressure limit of up to 1.99 MPa. Then, the effect of composite support with different cross-section shapes was analyzed and compared with FLAC 3D software, which proves the rationality of the design scheme. Finally, the composite support technology has been successfully applied in the mine. The engineering application shows that the final deformation of the surrounding rock is less than 100 mm for more than three years of roadway support, and the support body has good mechanical properties, effectively controlling the large section soft Convergent deformation of rock roadway.