MECHANICAL BEHAVIOR OF SALT ROCK WITH DISCONTINUOUS FISSURES WITH UNIAXIAL COMPRESSION TEST

This paper examines the mechanical behavior of salt rock containing fissure. The uniaxial compressive tests are carried out with a servo-controlled test machine RMT-150B.The effect of discontinuous fissures on strength and deformation of salt rock are analyzed. The discontinuous fissures coalescence the behavior of salt rock and its transfixion mode. The discontinuous fissure extension evolution is mainly divided into two types. The main fissures extended from the initial discontinuous fissures of salt rock specimens are the first type. The second type is that the initial discontinuous fissures of specimens are closed and then new micro-fissures are initiated from other place. They are gathered together and formed the main fissures. At the same time, the secondary fissures grow tardily. The tensile transfixion mode and tension-shear transfixion mode are the main transfixion models for salt rock containing discontinuous fissures. Influenced by their own structure compactness, the paths of fissures coalescence presents obvious zigzag line. Effect of vertical transfixion fissures on deformation modulus of salt rock is larger than that of inclined crack.