Experimental study on the seismic performance of prefabricated frame piers

Abstract

Prefabricated assembly technology can speed up the construction process and is widely used in the construction of urban bridges. However, research on the seismic performance of prefabricated frame concrete piers is scarce, and the seismic performance of prefabricated frame concrete piers with different connection forms must be urgently evaluated. In this study, three prefabricated frame concrete piers with different connection forms–namely cast-in-place (CIP), grouted splice sleeve connection (PC-S), and grouted corrugated duct connection (PC-C)–were designed and fabricated. Through quasi-static testing, the seismic performances of the CIP, PC-S, and PC-C specimens were evaluated using bearing capacity, displacement ductility, stiffness degradation, energy dissipation capacity, etc. as evaluation indexes. Based on the plastic damage theory of concrete, a finite element model was established. The test results showed that all the three specimens experienced flexural failure, and their load–displacement hysteretic curves were similar in shape (i.e., shuttle-shaped). The bearing capacity and ductility coefficient of the PC-S specimen were 95.7% and 77.5% of the CIP specimen, respectively, and those of the PC-C specimen were 93.0% and 92.5%, respectively. The stiffness degradation trends of the three specimens were similar, but the PC-S specimen exhibited the largest initial stiffness, and the stiffness of the PC-S and PC-C specimens at failure was 86.0% and 95.7% of that of the CIP specimen, respectively. When the CIP specimen failed, the cumulative energy dissipation values of the PC-S and PC-C specimens were 16.7% and 14.2% lower than that of the CIP specimen, respectively. The numerical simulation curves fitted well with the test curves, which verified the accuracy of the test results. The seismic performances of two kinds of the prefabricated bridge piers were close to the CIP specimen. When the strength of connectors and sealing material meet the requirements, prefabricated frame concrete piers can be preferentially selected for medium and low seismic areas.