Exploration using SPAC and MASW(CMPCC) at Yoshino Fishing Park, Jyoso City, Ibaraki, Japan where the ground failure by liquefaction took place due to the 2011 off the Pacific coast of Tohoku earthquake
Abstract
We report the result of a case study of the exploration using SPAC and MASW (CMPCC) that was conducted in a liquefied site due to the 2011 off the Pacific coast of Tohoku Earthquake. Very loose sand or muddy silt layers of Vs equal to or less than 100 m/s are detected within the depth of 10 m. According to the Fs method of NIST, a high liquefaction potential is evaluated at the site. This case study shows that the combination of MASW (CMPCC) and SPAC is useful to explore shallow soil layers for evaluation of liquefaction potential and also that there is a possibility to mistake the first higher mode in place of fundamental one for determination of dispersion curve if SPAC is not conducted together.