Analysis of Residual Displacement of Combined Base Isolated Structure

Residual displacement is disadvantageous to combined base isolation system, as it may cause the structure to overturn when it is big enough. To elucidate the mechanism of the system residual displacement after earthquake, the motion equation of the system was established. Through the theoretical analysis, the calculating formula was given, and residual displacement was found relevant with horizontal stiffness, the max friction forces of the sliding bearings and the input ground motion. With this method, the results of an example show that the friction coefficient of sliding bearings is the key influence factor of the residual displacement, and the way of how to figure out the value of the friction coefficient is recommended in this article.