Research On Smooth Blasting Of Hydraulic Tunnel And Damage To Surrounding Rock

In view of the traditional small section hydraulic diversion tunnel excavation method,the quality of the tunnel contour surface is poor,the surrounding rock disturbance and destruction are large,and the underbreak is obvious,which can not meet the efficient construction and economic construction.The problems of safe construction and so on.In this paper,the quality of smooth blasting in hydraulic tunnel is studied by means of theoretical analysis,numerical simulation and field test.Firstly,the research status and theory of rock blasting mechanism,blasting theory model,surrounding rock damage and smooth blasting technology are analyzed and summarized.Then,the hydraulic tunnel of river bottom is used as the engineering background.Ansys/ls-dyna is used to analyze the influence of different spacing between adjacent holes and different thickness of smooth blasting layer on smooth blasting and the disturbance of surrounding rock.The variation rule of the penetration effect along the surrounding hole spacing and the regularity of the surrounding rock disturbance intensity and the degree of fragmentation of the smooth blasting layer with the thickness of the detonation layer are obtained.Finally,through the field test of the hydraulic tunnel of the river bottom reservoir,the improved smooth blasting scheme and the original blasting plan are compared and analyzed,and the smooth blasting plan is improved,the blasting quality is good,the quality of the tunnel's hole formation is improved,the over and under excavation is obviously reduced,and the stability of the surrounding rock is improved.It has brought good economic results for the project construction,and verified the feasibility of the smooth blasting scheme improved by numerical simulation method,which provides a reference for the quality and safety of the excavation of the small section hydraulic tunnel.