Safety analysis of independent columns mounted on isolated bearing system

Abstract

This paper explores the safety performance of independent column mounted on isolated bearing. Considering large displacement of the isolator bearing under earthquake, the accumulated permanent deformations in the independent column may render gravity forces the dominant forces and make the system collapse by lateral instability. By means of dynamic response simulation of the system under seismic excitations, the safety of system is derived by optimality method and expert systems. The results show that the safety of system mainly depends on the lateral force, irrespective of the axial force. The lateral force is largely influenced by the displacement of the system. The absolute value of the constraint moment has significant effect on the safety of column. The more the absolute value of the constraint moment is, the worse the safety of system is. The independent column is impossible to be instability with an adequate section of column employed.