Behavior of segmental precast posttensioned bridge piers under lateral loads

Abstract A segmental precast posttensioned (SPPT) bridge pier is an economic recentering structural system. Understanding the seismic behavior of a SPPT system is an important step toward its application in high seismic zones. This paper presents a detailed three-dimensional finite-element (FE) model that was developed using the ABAQUS platform. A brief description and discussion of cyclic tests on eight large-scale SPPT piers is also presented. Four of the piers were constructed and tested to a predefined degree of damage. Then, these piers were retrofitted and retested. The FE models developed and presented in this paper predicted the backbone curves of the piers that were tested directly after construction with an average error of 7% for drift angles smaller than 2.5%. For drift angles greater than 2.5%, the average error reached 13%. For piers that were retrofitted and retested, the error in predicting the backbone curve depended on the state of damage before the retest. When preexistent microcracks were not severe, the FE models were able to predict the backbone curves with an error of approximately 12%. However, the error significantly increased and reached a value of approximately 31% when the preexistent microcracks were severe. In addition, the FE models confirmed the experimental observations and showed that the SPPT pier system is able to withstand large lateral drift angles with minimal damage. Finally, sensitivity analyses using the FE model showed that the model is sensitive to the softening behavior of the concrete material constitutive law.