Study on damage characteristics of rock mass under blasting load in Ling'ao Nuclear Power Station, Guangdong Province

Sonic wave tests have been conducted in the construction site of Ling'ao Nuclear Power Station (LNPS) in Guangdong Province, China. Based on the change rate of sound wave speed before and after blasting, damage zone size of surrounding rock has been determined. On the other hand, a statistics-based damage variable of rock mass has been proposed based on micromechanics. Damage zone size of rock mass under blasting is thus studied using a hybrid LS-DYNA and FLAC scheme. It is reported that the numerical simulation results agree well with the site monitoring results, and the damage threshold for the rock in site of LNPS, D_cri, is 0.2. The variation of damage zone size with charge weight has been analyzed by numerical simulations. It is observed that the rock damage zone size increases with charge weight. Damage zone depth of rock mass under blasting is less than damage zone radius. The damage zone radius is approximately 3 times of the damage zone depth.