大断面极软岩巷道钢管混凝土支架复合支护技术  

Composite supporting technology of concrete-filled steel tubular support in extremely soft rock roadway with large section

作　　者：刘珂铭[1,2] 高延法[2] 张凤银[2] 

机构地区：[1]临沂大学土木工程与建筑学院,山东临沂276000 [2]中国矿业大学(北京)力学与建筑工程学院,北京100083

出　　处：《采矿与安全工程学报》2017年第2期243-250,共8页Journal of Mining & Safety Engineering

基　　金：国家自然科学基金项目(51474218)

摘　　要：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。To solve the supporting issues of severe deformation of large-section-soft-rock roadway in the temporary water sump （level ＋786 m underground） in Qingshuiying mine, the characteristics of roadway deformation and failure were investigated, the physical and mechanical parameters of the sur- rounding rock samples were tested, and reasons for surrounding rock deformation and failure were ana- lyzed. The research has found that the surrounding rock in the temporary water sump has the property of high swelling and extreme softness, and its deformation was mainly caused by slipping and expansion of clay minerals. Based on the research above, an enclosed composite supporting scheme was proposed, which integrated erect elliptic concrete-filled steel tubular support （CFST support）, bolt-mesh-shotcret- ing, strengthening anchor cable, and steel fiber reinforced concrete arch wall, mechanical model of strengthening confined ring mainly based on CFST support was established, and theoretical calculation indicates that the confined ring structure can supply 1.99 MPa supporting resistance for the outside surrounding rock. After that, the supporting effect of different section shapes were analyzed through FLACaDto verify the rationality of the design scheme. The composite support technique has been suecessfully applied in the underground site for more than 3 years, and the accumulative deformation of surrounding rock is less than 100 mm. Meanwhile, each supporting structure has good mechanical per- formance, which can effectively control the severe deformation of surrounding rock.

关 键 词：大断面 极软岩 钢管混凝土支架 承压环 封闭式 复合支护 

分 类 号：TD353[矿业工程—矿井建设]