Pushover and shaking table tests on a rocking-governed column-footing model on dry dense sand
Journal
Journal of the Chinese Institute of Engineers, Transactions of the Chinese Institute of Engineers,Series A/Chung-kuo Kung Ch'eng Hsuch K'an
Journal Volume
41
Journal Issue
3
Pages
247-258
Date Issued
2018
Author(s)
Abstract
Footings are normally used on firm ground. Previous studies have indicated that footings with large vertical bearing capacity have small settlement and recentering characteristics during excitation. The rocking foundation design is, therefore, considered quite suitable for a firm ground condition; however, some 1 g shaking table tests have shown that rocking structures still might have stability problems leading to toppling. In this study, we conducted pushover and shaking table tests on a rocking-governed column-footing model on dry dense sand to investigate the performance of a rocking structure on sturdy ground. Even in a dense soil condition, the structure had a longer period response than in the fixed-base condition, but this did not necessarily reduce the seismic demand on the structure. The major source of rocking isolation is that the maximum acceleration response of the structure is limited by the ultimate moment capacity of the footing; however, it is important to note that extensive rocking may induce a larger permanent rotation, which may influence the functionality of structures, and also may lead to structure instability, such as foundation twisting observed in this study.
Type
journal article