Study On Dynamic Response Characteristics Of Surrounding Rock And Bolt(Cable) In Deep Roadway Under Explosive Loading

In this paper,through the dynamic and static mechanical tests of fine sandstone samples taken in deep roadway,the dynamic and static mechanical properties of deep fine sandstone are studied,and a set of dynamic constitutive(HJC)parameters related to pressure and containing damage,which are suitable for deep fine sandstone,are determined.Based on this constitutive parameter,considering the influence of initial stress at different depths,the deep rock cutting blasting is carried out.At the same time,combined with the engineering practice,the numerical research on the dynamic response of deep anchorage roadway under the explosive dynamic load is carried out.The main results are as follows:(1)Under the action of confining pressure,with the increase of loading rate,peak strain is larger and the peak strength is larger.Under the same loading rate,with the increase of confining pressure,the peak strain is smaller and the peak strength is larger and larger.(2)Under the impact load,the fine sandstone experienced five processes: the first crack appeared,the second crack appeared,the crack first penetrated,the local crushing area appeared and finally crushed completely.(3)The dynamic compressive strength and tensile strength of water saturated fine sandstone are closely related to its own structural characteristics and the role of water.Water improves the dynamic compressive strength and tensile strength enhancement factor of fine sandstone,and the improvement of dynamic tensile strength enhancement factor of fine sandstone is more significant.(4)In cut blasting,the compression damage of the rock mass around the cut hole is different from that around the explosive;with the increase of the depth of the rock mass,the coupling effect of the stress wave and the initial ground stress is weaker and weaker.(5)Under the action of explosion load,the effective stress peak value and vibration velocity peak value of surrounding rock of deep roadway increase with the increase of depth,and the increase rate decreases with the increase of depth.(6)With the increase of depth,the initial axial force and shear force of bolts in deep roadway increase,and the axial force of roof bolts is greater than that of side bolts.The influence of dynamic load on the shear force of roof bolt is greater than that of side bolts.