Shaking table testing on high-rise buildings considering liquefiable soil-structure interaction

Abstract:

Shaking table model test on high-rise buildings considering liquefiable soil-structure interaction is described in this paper. A flexible container was fabricated to minimize the box effect. Saturated sand soil was employed as model soil. In the test, macro-phenomena of high-rise building in ground of soil liquefaction due to natural earthquake are reproduced well. Some important findings from the present tests are as follows. The mode shape of the system is different from that of the structure on the fixed base in that there are rocking and swing at the foundation. The natural frequency of interaction system decrease and the damping ratio of soil increase with the increase of the shaking. The liquefied soil can filter and isolate vibration. The phenomena of transient minus pore pressure occurred in the test. Pore water pressure does not always dissipate in short time immediately after the excitations, but it may keep on increasing too. The distribution of the strain amplitude along the pile is the shape where the large strain is at the top of the pile and the small strain is at the tip of the pile. And the distribution of the contact pressure on the pile-soil interface is related to the excitation magnitude.