STUDY ON DYNAMIC RESPONSE OF RECLAIMED AND SOFT GROUND OF MAN-MADE ISLAND IN KOBE HARBOR DURING 1995 HYOGOKEN NANBU EARTHQUAKE AND LIQUEFACTION CONTROL

摘要

Earthquake response of filled man made island of the Kobe harbor during the 1995 Hyougoken Nambu Earthquake is dealt with. Dynamic response characteristics and effects of SPT N-value on liquefaction for such soft grounds are examined. The one-dimensional analysis based on effective stress analysis method considering cyclic mobility is adopted. For modeling of the soil layers, soil parameters such as SPT N-value by standard penetration test and shear wave velocity Vs by PS logging is used. Absorbed energy by hysteresis loop of soils are also calculated as well as ordinary responses such as acceleration, stress and strain responses. The relation between distribution of absorbed energy and liquefaction becomes clear. As conclusion, the portion where liquefaction occurs becomes deeper and the damages such as ejection of water and soil and resultant subsidence can be restrained by increase of SPT N-value.