SEISMIC PERFORMANCE OF PREFABRICATED CORE STEEL TUBE REINFORCED CONCRETE COLUMNS

Prefabricated assembly accelerates the building construction process. A primary concern related to prefabricated assembly is the increased fragility of the connection between precast members compared to cast-in-situ members. On the other hand, core steel tube reinforced concrete (CSTRC) columns are increasingly being used in high-rise structures to provide effective axial and lateral force resistance. This study proposes a prefabricated core steel tube reinforced concrete (PCSTRC) column which capitalizes on both the strength of the CSTRC column and the advantages of precast manufacturing, as shown in Fig. 1. The connection is designed to guarantee the integrity of the whole column. Two full-scale PCSTRC columns with varying axial loads and two controlled specimens, namely a monolithic CSTRC column and a conventional reinforced concrete (RC) column, were fabricated and tested under quasi-static cyclic loading in order to investigate their seismic performance. The test results demonstrate that all the columns experienced typical flexure-controlled failure, while the PCSTRC columns suffered less visual damage than the monolithic controlled specimens. The PCSTRC column performed satisfactorily in terms of strength, stiffness, ductility, and general hysteretic behavior and had significantly greater load-carrying and energy dissipation capacities than the conventional RC column. In addition, there were no apparent differences between the capacities of the CSTRC and PCSTRC columns. As axial load increased, the deformation capacity of the PCSTRC column decreased. Overall, the proposed prefabricated composite column demonstrates good seismic performance and can be considered for use in building construction. © 2023 Ernst & Sohn GmbH.