一つの不連続面のある岩石試験片の一軸圧縮

Abstract

For the purpose to investigate the behaviour of jointed rock mass, uniaxial compression tests were performed for specimens each including one artificial joint, horizontal or vertical, and stratiform rock specimens composed of two different rock species which were combined longitudinally. Following results were obtained.1) Strength and deformability of specimens including horizontal joint, are almost equal to those of intact rocks, and are not affected by the planar joint.2) For specimens including vertical joint, both strength and Young's modulus are lower than those of intact rocks.3) For the stratiform specimens, failure occur at the stress, that equals the strength of the weaker rock species which ν/E value (ν: Poission's ratio, E: Young's modulus) is higher. But the mode of failure vary according to combinations of rock species and loading rates. For combination of rock species which strengths are relatively high, both rock species will fail si multaneously. Even for those stratiform specimens, which are composed of two rock species which strengths differ considerably, simultaneous failure may occur in the case of low loading rate. It is considered that the mode of failure results from the interaction of two rock species at the joint.4) It is found by FEM analysis, that failure mode of the stratiform rock specimens mostly depends on the difference of ν/E values of two rock species.