Inversion of dynamic parameters of rock mass based on field blasting vibration

How to obtain the dynamic parameters of rock mass quickly and precisely is a popular and difficult problem in geotechnical engineering, which plays a very important part in the engineering design or construction. Currently, scholars have developed many methods to obtain these parameters, such as in-situ testing method, empirical formula and so on. However, these methods need large investments and long construction period, etc., which cannot obtain the dynamic parameters precisely and quickly in the engineering scale. A new method for estimating the rock parameters based on field blasting vibration signals is proposed. By identifying the arrival times of P and S waves, the propagation velocities of P and S waves are calculated, and the parameters can be obtained. By analyzing the field blasting vibration signals in Fengning pumped-storage power station, the results demonstrate that the dynamic elastic modulus of the rocks inversed by the field blasting vibration signals is higher than its static one given by Beijing Engineering Corporation Limited, i.e. the ratio is about 2.2~2.9, and the inversed dynamic Poisson's ratio is lower than its static one, 0.9~0.975 times the static one. Therefore, the proposed method based on field blasting vibration provides a new and effective way for obtaining the dynamic parameters of rock mass.