Rocking Response Analysis of Self-Centering Walls under Ground Excitations

This paper presents a numerical procedure to simulate the rocking response of self-centering walls under ground excitations. To this aim, the equations of motion that govern the dynamic response of self-centering walls are first formulated and then solved numerically, in which three different self-centering wall structural systems are considered, that is, (i) including the self-weight of the wall only, (ii) including posttensioned tendon, and (iii) including both posttensioned tendon and dampers. Following the development of the numerical procedure, parametric studies are then carried out to investigate the influence of a variety of factors on the dynamic response of the self-centering wall under seismic excitations. The investigation results show that within the cases studied in this paper the installation of posttensioned tendon is capable of significantly enhancing the self-centering ability of the self-centering wall. In addition, increasing either the initial force or the elastic stiffness of the posttensioned tendon can reduce the dynamic response of the self-centering wall in terms of the rotation angle and angular velocity, whereas the former approach is found to be more effective than the latter one. It is also revealed that the addition of the dampers is able to improve the energy dissipation capacity of the self-centering wall. Furthermore, for the cases studied in this paper the yield strength of the dampers appears to have a more significant effect on the dynamic response of the self-centering wall than the elastic stiffness of the dampers.