Lade의 3차원 파괴규준을 이용한 현무암의 전단강도 산정

In this study, a series of triaxial tests to Jeju basalt were carried out and then shear strength parameters of rock were estimated by the Lade’s three-dimensional failure criterion. Also, the characteristics of shear strength parameters and failure plane which were estimated by the three-dimensional failure criterion were analyzed and this failure criterion was compared with the Mohr-Coulomb failure criterion. The variables of ŋ₁ and m are derived from the relationship between (I₁³/I₃-27) and (P a /I₁) during the failure period using the Lade’s three-dimensional failure criterion. The failure plane size of Tracy-basalt has the largest plane and that of Scoria has the smallest plane among other octahedral planes which is the three-dimensional failure plane. Also, the failure plane of Tracy-basalt is formed as a triangle and that of Scoria is formed as a circle among other octahedral planes. As the result of comparison with the triaxial test results and the Lade’s failure envelope and the Mohr-Coulomb failure envelope, the Lade’s failure envelope matched up under higher stress, while the Mohr-Coulomb failure envelope matched up under lower stress. Also, the Lade’s three-dimensional failure plane is larger than the Mohr-Coulomb three-dimensional failure plane. It means that the shear strength parameters estimated by the Lade’s failure criterion is larger than that of the Mohr-Coulomb failure criterion.