Performance of piles as evaluated by three-layer model

The damage features of the spherical storage tanks at the time of the 1995 Kobe earthquake were introduced, together with the in-situ soil conditions. In an aim to clarify the cause of the distress, back-analysis was made for the foundation piles based on the three-layer model proposed previously. The results of the analysis disclosed that the bending moment near the pile head and at the depth of the boundary between the liquefied and the underlying unliquefied layer reached values close to or in excess of the moment at yielding or at failure of the pre-cast reinforced concrete piles.