Using P wave modulus to estimate the mechanical parameters of rock mass

Obtaining reasonable and reliable mechanical parameters of rock mass in engineering is a challenge. These parameters are difficult to obtain from a large sum of field tests due to the restrictions of time and costs. In this paper, linear equations of estimating rock mass mechanical parameters based on the P wave modulus are proposed through dimensional analysis. The field tests data of the Xiangjiaba, Baihetan, and Jinping I dam foundations are discussed to verify the universality and applicability of these linear equations. In addition, a new equation for calculating the disturbance factor D based on the P wave modulus is presented to estimate the mechanical parameters of rock mass in the disturbed zones, and then the field test data of the Three Gorges Project (TGP) shiplock slope are studied to verify the equation. The results show that the linear equations based on the P wave modulus have higher correlation than other function equations based on the P wave velocity. Therefore, the empirical equations using P wave modulus are feasible for estimating the mechanical parameters of rock mass.