强膨胀软岩巷道锚网喷架联合支护技术研究

强膨胀软岩巷道的支护问题是西部地区矿井建设中普遍遇到的难题。为解决强膨胀软岩遇水泥化、崩解等给巷道掘进、支护等工程带来的困难,以强膨胀软岩巷道支护工程为研究对象,通过理论分析和现场调研,研究强膨胀软岩巷道变形机理;利用有限元分析软件MIDAS/GTS建立强膨胀软岩巷道数值仿真模型,分析了锚网喷架联合支护时巷道塑性区范围、表面位移和钢支架的受力特征。进行现场测试,获得了巷道围岩变形和锚杆受力变化规律。结果表明,采用钢支架与锚网喷构成联合支护体系可有效提高支护结构整体刚度,提升围岩的自稳能力和自承能力。

Technical engineering approach to the anchor net spray frame composite support for the strong swelling soft rock roadway

The present paper takes it as its research object to solve the problems caused by the strong swelling of the rock based on the theoretical analysis and the field investigation of the deformation mechanism of this way.Needless to say,it involves the trace of the characteristics of low strength,high expansibility and rheological property,for it is the above mentioned characteristic features that bring about difficulties to the tunnel excavation and its supports.Facing the difficulties,we have established a numerical simulation model of the strong swelling soft rock roadway with the finite element analysis software named MIDAS/GTS and analyzed and examined the range of the plastic zone,the stress distribution,the stress of the mixed structure,the displacement of the surface and the mechanical characteristics of the steel support for the strong swelling soft rock roadway in combination with the anchor net and shotcrete support so as to find the deformation mechanism of the surrounding rock and its changing regularity of the rock bolt stress.The results of the above investigation and analysis show that there exists a small range of plastic zone in the joining part between the steel frame and the anchor net spray.And,if the stress distribution of the surrounding rock strata is uniform,the stress distribution of the anchor shotcrete supporting structure would be even,or balanced,with the stress being smaller than that of bolting and shotcreting.And,in so doing,the overall stiffness of the supporting structure for the strong swelling soft rock roadway can be effectively improved,and the self-stabilization ability and the self-bearing capability of the surrounding rock can be greatly improved.The research results of the given paper can thus be expected to provide some references for the roadway support under the geological conditions of the strong swelling soft rock,and can thus be of great engineering significance to solve the problem of supporting in the strong swelling soft rock roadway.