ABSTRACT

Static strength has traditionally been considered as rock strength in the foundation bedrock for seismic design in Japan. The appropriate evaluation of dynamic strength instead of static strength became necessary for dynamic response analysis following the Great East Japan Earthquake. Therefore, we previously proposed a mathematical model to evaluate the dynamic strength for intact rocks. In this study, we performed laboratory tests and validated the model for discontinuity by using an artificial rock. As a result, the dynamic strength exceeded the static strength in the experimental and calculated results. However, the influence of fatigue and loading rate were less, compared to the cases of intact rocks. Therefore, the dynamic strength of the discontinuity does not greatly differ from static strength.