抄録
Following the Miyagiken-oki earthquake of June 12, 1978, signs of considerable liquefaction were observed over the reclaimed sand deposit in the area of Ishinomaki fishery port. Three oil storage tanks constructed in thin area but on the deposit compacted survived without any damage notwith-standing the considerable liquefaction that had developed in the surrounding area. After the earthquake, undisturbed sand samples were taken by means of Osterberg piston sampler both from the compacted deposit and from the uncompacted deposit. Laboratory cyclic triaxial shear tests were performed on these specimens to determine the in-situ cyclic strengths of the sands. The cyclic strengths thus determined were incorporated into a simple analysis to determine the potential for liquefaction in these two deposits. The results of the liquefaction analysis were discussed in the light of the construction record and the observed performances of the tanks and deposits during the 1978 earthquake.
