Title: Multi-“Hinge” Hierarchical Activation to Improve Structural Robustness of Post-tensioned Rocking Piers
Author(s): Royce Liu and Alessandro Palermo
Publication: Symposium Paper
Appears on pages(s): 202-225
Keywords: bridge pier; columns; post-tensioned; rocking; seismic; low damage; robustness; structural redundancy
Structural redundancy and robustness are necessary to protect against beyond design seismic loads. In this paper, the idea of improving these properties is applied to single column bridge piers using the hybrid PRESSS/Dissipative Controlled Rocking (DCR) system through a novel technique called hierarchical activation. This technique involves the inclusion of more “hinges” (rocking interfaces) and or sets of dissipative devices in such a way that they are activated in a hierarchy with respect to the displacement of the structure. A 2/3 scale cantilever column designed to use this technique was tested. The specimen was capable of multiple configurations, two of which are focused on in this paper: conventional DCR; and segmented DCR (segDCR), which used hierarchical activation. Hierarchical activation was successfully achieved in the experiment; and despite the global response being similar, segDCR was found to be advantageous with respect to reducing the cyclic strain demand on the dissipaters.