Experimental and Simulation Studies on the Seismic Performance of Ⅰ-section Steel-Concrete Composite Columns

摘要

This study analyses the working mechanism and seismic performance index of Ⅰ-section steel-reinforced concrete columns with concealed double steel plates and bottom-strengthened Ⅰ-section concrete-filled steel tube columns subjected to compression-bending load. For this purpose, six column models with different constructions were tested under horizontal low cyclic loading. Based on the experiments, the load-bearing capacity, stiffness and degradation process, ductility, hysteretic energy dissipation capacity and failure characteristics of the models were analysed. The formulae for calculating the load-bearing capacity for the normal and oblique sections of Ⅰ-section steel-concrete composite columns were derived, and the finite element (FE) numerical simulation of the classical specimens was performed. According to the results, the load-bearing capacity, ductility and seismic energy dissipation capacity of the bottom-strengthened Ⅰ-section steel-concrete composite columns are obviously improved when compared with those of the conventional Ⅰ-section steel-concrete composite columns. Moreover, the calculated and FE numerical simulation results are found to be in good agreement with the experimental results. Further, the bottom-strengthened Ⅰ-section steel-concrete composite column shows better seismic behaviour and higher energy dissipation capacity under suitable constructional requirements, indicating their suitability for constructing high-rise buildings.