지반-기초-구조물 상호작용을 고려한 말뚝 기초 구조물에서의 지진 하중 평가

Abstract

In this study, a series of dynamic centrifuge tests were performed for a soil-foundation-structural interaction system in dry sand withvarious embedded depths and superstructure conditions. Sinusoidal wave, sweep wave and real earthquake were used as input motionwith various input acceleration and frequencies. Based on the results, a natural period and an earthquake load for soil-structureinteraction system were evaluated by comparing the free-field and foundation accelerations . The natural period of free field is longerthan that of the soil-foundation-structure system. In addition, it is confirmed that the earthquake load for soil-foundation-structuresystem is smaller than that of free-field in short period region. In contrast, the earthquake load for soil-foundation-structure interactionsystem is larger than that of free-field in long period region. Therefore, the current seismic design method, applying seismic loading offree-field to foundation, could overly underestimate seismic load and cause unsafe design for long period structures, such as high-risebuildings.