Effect of Fast Loading on the Seismic Performance of SRUHSC Frame Structures

Abstract

Due to the high compressive strength and durability of ultra-high-strength concrete, SRUHSC (steel-reinforced ultra-high-strength concrete) frame structures have been used extensively in super-high-rise buildings. However, the SRUHSC showed obvious brittleness. Encasing structural steel in the material was recognized to be a good way of alleviating the problem of brittleness. The purpose of this study is to investigate the effect of the axial compression ratio on the seismic performance of a single-story, single-span SRUHSC frame structure under rapid loading. The failure mode, deformation, strength and stiffness degradation, energy dissipation capacity and residual displacement of the structure were compared and analyzed. The seismic performance of a single-story single-span SRUHSC frame structure is verified under the conditions of a fast loading rate and high axial compression ratio. The results suggest that the horizontal resistance capacity of structures can be significantly improved by fast loading in the elastic and elastic–plastic ranges. The ductility coefficient of the structure increases with the same axial compression ratio under fast loading. With an increase in loading rate, the secant stiffness of the structure is improved.

Keywords

• axial compression ratio
• ductility
• horizontal resistance capacity
• energy dissipation capacity
• stiffness degradation