| There are more and more high-cut slopes in the engineering construction,and the stability of high-cut slope has attracted wide attention.Blasting is the main means of engineering excavation,and the process is complicated,and the impact of blasting vibration on the stability of the slope is relatively few.In this paper,the author took the high-cut slope of factory building of Yangqu hydropower station as research object.The numerical simulation method was used to study the response of high excavation slope under dynamic load.Firstly,the process of grading excavation of the powerhouse of Yangqu hydropower station,the distribution law of rock mass stress and displacement in each stage,and the internal force and deformation of the bolt were analyzed in this paper.The excavation process was easy to produce unloading rebound,and the maximum displacement of rock mass due to unloading rebound was 8.42 cm.The maximum tensile stress of the bolt was 78.7MPa,which occurred at the corner of the slope and should be strengthened.Then,the stability factor of slope under static condition was 1.25 by the strength reduction method,which was greater than the national standard.When the slope reduction coefficient was 1.25,the sliding body produced was on the surface of the slope,resulting in local sliding.There was no plastic zone in the slope,so the surface protection of the slope should be strengthened.The diversion tunnel was located at the bottom of the slope of the rear side of the factory building,and it was excavated by blasting.The local 3d model of rear slope of the factory building was established without considering the influence of overburden on the stability of the slope.Under static conditions the safety and stability coefficient was 2.2.Added curves of blasting vibration acceleration in the 2# tunnel face for numerical calculation which was 108 m from the slope.The signal of field monitoring was filtered and de-noised by CEEMD filter based on correlation function.By numerical calculation,the velocity curves of each point of the slope were obtained Compared with the velocity curves after filtered,the error was within 14.96%,which verified the reliability of the numerical calculation.Under blasting load,the safety and stability coefficient of slope was 1.887,which decreased by 14.23%. |
