On Hyogoken-Nanbu-earthquake (1995.1.17), lateral flow and liquefaction occured on the ground near by the sea in Ashiya City. A number of buildings in the area were inclined to seaside. This report is the results of the observation on the damage of pre-cast concrete piles (diameter : 50cm, length : 26m)on a damaged building. At the southern footings of the building, the piles were inclined largely and were broken both at about 3.4m depth and at pile-top. 0n the other hand, the piles at northern footings were broken only at pile top. We estimate that the collapse of the piles of northern footings occurred by inertia force of the superstructure and that the collapse of the piles of southern footings occured by landslip. The northern footings are not included in landslip area, then the slip angle is larger than 15°.
