Settlement of Rigid Circular Foundations during Seismic Shaking in Shaking Table Tests

Abstract

The settlements of structures resting on saturated sand deposits are examined in shaking table tests. Two series of tests are conducted to examine the effects of the duration of seismic shaking and the group effects of closely spaced foundations. The models of rigid circular foundations are founded on the surface of saturated clean fine sand, and seismically excited. The settlements of model foundations and the distributions of excess pore-water pressures induced around the model foundations are observed. In one of the test series, the settlements occurring during shaking are found to increase as the durations of shaking increase; however, the settlements occurring after the end of the shaking remain almost the same, regardless of the durations of shaking. The total settlements are, therefore, found to increase as the durations of shaking increase. In the other test series, the settlements occurring during shaking remain almost the same, regardless of the spacing. However, the settlements occurring after the end of shaking are different, where the more closely spaced foundations tend to be subjected to smaller settlements.