Experimental and analytical research on steel reinforced high-strength concrete columns with different steel sections

Abstract

Steel reinforced concrete columns are the key vertical load-bearing members in the frame composite structures of super high-rise buildings. The steel sections and steel ratios of these columns are the major factors affecting their seismic performance. In this paper, four large steel reinforced high-strength concrete (SRHC) columns were designed. The influences of closed and open steel sections on the seismic performance of SRHC columns with different steel ratios were analyzed. The test results show that the SRHC columns with closed steel sections had plumper hysteresis loops, a higher and more stable bearing capacity, and greater deformation and energy dissipation capacities than the columns with open steel sections. The influences of the steel ratio on the plumpness of the hysteresis loops, residual deformation and energy dissipation capacity of the columns with open steel sections were greater than those of the columns with closed steel sections. The fiber-based method was adopted to predict the F-Δ curves and N-M interaction curves of the SRHC columns with closed and open steel sections. The calculated results show good agreement with the test results, and the experimental results can provide evidence for the seismic design of SRHC columns with both closed and open steel sections.