Abstract
In order to reveal the mechanical characteristics for in-situ volcanic soils, triaxial tests for undisturbed and reconstituted specimens were carried out. SPT, CPT and SCP tests were also performed at the sampling sites. The test results showed that the effects of fabric anisotropy and welding on monotonic shear behavior are insignificant for crushable volcanic soils due to fabric change induced by particle crushing. Although the influences of grain size, fines content and welding on liquefaction strength for in-situ volcanic soils seem to be strong, liquefaction strength and its anisotropy effect for brittle pumice are reduced with the increase in confining pressure and fabric change. Moreover, since in dynamic penetration test the particle crushing of volcanic soil grounds occurs, it was found that the correlations between N-value and strength parameter are different from that of sandy grounds.
