Study On The Deformation And Destroyment Of Deep Tunnel Surrounding Rock And Supportment In Hengda Coal Mine

As the shallow coal resources has been exhausted,the mining of coal resources is becoming more and more deep.The high crustal stress is becoming more and more outstanding and becoming a main factor of deformation and stability of tunnel.The crustal stress of deep stratum is variable under the different conditions of geological structure.What is different from the shallow mining is that the side press coefficient can be larger than one or smaller than one.There will be some limitations if the traditional shallow deforming and destroying laws of surrounding rock is adjusted to the deep rock.When the condition of crustal stress is not prospected clearly,it is not true that the side press coefficient may be larger than 1 or larger than 1.5.The different conditions of crustal stress will lead to different manners of deformation and destroyment,so the different measures of supportment and enforcement should be taken correspondingly.So it must do a deeper study on the features of deforming and destroying mechanism of deep tunnel surrounding rock in order to take the supporting and enforcing measurement which is appropriate to the deep tunnel surrounding rock.The deep rock is in a state of static equilibrium through a long geological process.The static equilibrium is destroyed by mining tunnel and tends to a new state of stability.The evolution of stress in the inner surrounding rock have a decisive effect on the deformation and destroyment of surrounding rock.Corrently the theory always uses the elastoplastic theory to study the distributing and varying laws of stress,strain and deformation of surrounding rock,in order to learn the deforming and destroying mechanism.In this way,the tunnel can be supported more well and safely.So according to the Mining Science,Advanced Rock Mechanics,Elastic Plastic Mechanics and many other theorys,this paper uses the large finite element numerical simulation software ANSYS to do the numerical analysis on the features of deformation and destruction of tunnel surrounding rock and on the different supporting effects of the same supporting and enforcing manner in different side press coefficients as 1.5,1.0 and 0.5,based on the practical engineering background,transporting materials tunnel of 125 mining zone in HengDa mine.It studys and perfects the deformating and destroying mechanism of deep tunnel rock as well as the supporting technology in order to adjust to the complex state of crustal stress in the fact.In this way,this paper may provide a worthy reference to the tunnel's driving and supporting in this engineering situation.This paper studys the following contents mainly:First of all,it separately analyses the distributing and varing laws of plastic zone,maximum principle stress,minimum principle stress and VonMises equivalent stress in the inner surrounding rock in every different side press coefficients in order to learn the laws of deformation and destruction of surrounding rock.Then it do the comprehensive and comparative analysis of the three different conditions to summarize the distributing and varing laws of plastic zone,maximum principle stress,minimum principle stress and VonMises equivalent stress in the inner surrounding rock,so it can get the deformation and destruction laws of surrounding rock between the three different side press coefficients.It analyses the variations of plastic zone,maximum principle stress,minimum principle stress and displacement of the tunnel with the sanme supporting manner in different side press coefficient.It also do the comprehensive and comparative analysis of plastic zone,maximum principle stress,minimum principle stress and displacement between the three different side press coefficients according to the numerical simulational result of deformation and distribution,so it can get the laws that different side press coefficients have influence on the supportment.