An Investigation on the Pile Foundations Damaged by Liquefaction at the Hyogoken Nanbu Earthquake

This paper describes an investigation on the foundations damaged by liquefaction of a thick reclaimed layer at the Hyogoken Nanbu Earthquake. The investigation was intensively performed both on soil properties and on the drilled shafts of a building that was under-construction at the earthquake. The shafts were excavated around their connection to the pile caps and core-drilled at the center of the shafts to a depth of 15m. It is found that the shafts tilt more than 1/20 from the vertical axis and that cracks arise at the top and the middle points of the shafts.