Abstract
In this study, a series of triaxial compression tests were conducted for basaltic intact rocks sampled in the northeastern onshore and offshore, southeastern offshore and northwestern offshore of Jeju Island, Korea. The strength parameters of Mohr-Coulomb shear failure criterion that represent cohesion and internal friction angle, estimated from the results of the triaxial compression tests were compared and analyzed with porosity(effective porosity), i.e. a parameter representing the vesicular properties of basalts. The results demonstrate that the relation between cohesion and porosity can be classified clearly as two different non-linear regression curves in accordance with two different linear relations in bulk specific gravity and porosity. As the porosity increases, the cohesion decreases exponentially. On the other hand, the internal friction angle decreases with increasing porosity.
