Vibration Response And Countermeasure Of Slope Blasting To Adjacent Large-scale Caverns Bow The Slope

In recent years,the hydropower construction gradually to the inaccessible alpine canyon in China,because of the complicated geological conditions narrow venues three-dimensional cross-construction,the construction are more and more difficult.high steep slope blasting excavation on the adjacent existing tunn has become an unavoidable problem.So It is of important theoretical significance and practical significance to study the influence of blasting vibration on the adjacent tunns.The paper takes the export of Changheba Hydropower Station spillway slope excavation system as engineering background.Based on the theoretical analysis,blasting vibration test,linear regression and numerical simulation,the blasting vibration response and control strategy of slope blasting to existing large tunns are studied,The results are as follows:(1)Through blasting vibration test and analysis of the slope blasting excavation on the adjacent existing different tunns The vibration response and its characteristics of the adjacent existing tunns were obtained on the the export of Changheba Hydropower Station.The response is not only rated to the explosive quantity and blasting center,but also to the spatial position of the bursting and the tunns,and the vertical vibration vocity is greater than the lev when the blasting position is above the tunn.The horizontal vibration vocity will play a major control role in the front of the tunn,and when the burst area is close enough to the position of the tunn,the peak vocity in the three directions is not very different.(2)Based on the fid test results combined with the numerical analysis method and the least squares method,the regression law of the blasting vibration propagation and the blasting vibration prediction formula of the excavated slope of the Changheba Hydropower Station are summarized as follows: 1)During the blasting of the tunns,the measured position of the tunns structure is different from that of the blasting space.The vibration vocity of the measured particles is also different,which shows that the blasting side of particle vocity is greater than the back side of blasting particle vibration vocity,vibration vocity and tunn floor corner vault and the side wall is far less than the position of the upper position.2)As the the evation of the blasting area gradually approaches the lower chamber,the vibration vocity in the vertical direction decreases with the increase of the evation,while the radial and tangen-tial vocity according to the specific spatial location analysis of blasting area and tunns point.3)the same evation,bursting area gradually close to the tunns,the impact on the tunns is also gradually increased.(3)Based on the law of slope vibration,the vibration response of the large-scale tunns is studied.In the process of excavation of the adjacent tuuns,the "pre-splitting first,upper and lower layers,layer control block,maximum explosive,tunn control measures of reinforcement engineering,and in the Changheba Hydropower Station exit slope project application practice,to achieve the slope gradient near the large group of safety and smooth digging.The results show that the slope blasting vibration response of the existing large tunns can be controlled by recognizing the law of the blasting vibration response and taking the necessary countermeasures,the slope can be safy and smoothly completed.of the excavation construction,the results are worthy of reference for similar projects.