Abstract: Rock mass has much higher compressive strength than tensile strength, so engineers concern about not only plastic compressive-shear damage around charge hole but also tensile damage near the free-face when blast occurs in rock with a single free-face. These damages may touch upon construction safety and even property loss if the free-face is just ground surface. Previous researches ignore either compressive-shear damage or tensile damage, thus the conclusions drawn are difficult to meet the needs of engineering. Based on reasonable modes of stress revision, this paper incorporates an existing damage constitutive model which can separately consider tensile damage and compressive-shear damage into the commercial FEM software, LS-DYNA. Cylindrical and spherical explosions in rock mass with a single free-face are then numerically simulated. The results show that this method can well predict the distribution and evolution of blast-induced compressive and tensile damages.

Key words: rock mass, single free-face, engineering blasting, damage model, numerical analysis