Experimental investigation on the cyclic behaviors of ultra-high-performance steel fiber reinforced concrete filled thin-walled steel tubular columns

摘要

This paper presents an experimental investigation on the cyclic behaviors of ultra-high performance steel fiber reinforced concrete filled thin-walled steel tubular columns under combined axial compression and cyclic lateral displacement loading. The failure modes, hysteretic behaviors, envelop diagrams, ductile performance, stiffness degradation and energy dissipation capacity were analyzed in detail. Notably, the cyclic behaviors of referenced high strength concrete and normal strength concrete filled thin-walled steel tubular columns were also studied to get a better illustration of the cyclic behaviors of ultra-high-performance steel fiber reinforced concrete filled thin-walled steel tubular columns. Furthermore, the effects of steel tube thickness, axial compression ratio, volume ratio of steel fiber and slenderness on the cyclic behaviors of ultra-high-performance steel fiber reinforced concrete filled thin-walled steel tubular columns were also investigated in detail. The test results indicate that the high strength concrete filled thin-walled steel tubular columns represent a poor cyclic behavior. However, replacing high strength concrete with ultra-high performance steel fiber reinforced concrete to infill thin-walled steel tubes can get an excellent cyclic behavior. Moreover, the cyclic behavior of ultra-high performance steel fiber reinforced concrete filled thin-walled steel tubular columns is also much better than that of normal strength concrete filled thin-walled steel tubular columns.