Experimental study on the seismic performance of composite columns with an ultra-high-strength concrete-filled steel tube core

Abstract

The ultra-high-strength concrete-encased concrete-filled steel tube column consists of a concrete-filled steel tube core and a rectangle-shaped reinforced concrete encasement. This article presents the seismic performance analysis of ultra-high-strength concrete-encased concrete-filled steel tube columns subjected to cyclic loading. Based on the measured load-lateral displacement hysteresis curves of six ultra-high-strength concrete-encased concrete-filled steel tube columns and two conventional RC columns, the seismic behaviours, such as the ductility, energy dissipation, stiffness and load-bearing capacity, were analysed. The effects of the arrangement of the stirrups and the layout of the prestressed steel strips on the seismic performance of the composite columns were critically examined. The test results indicated that the ductility and energy dissipation performance of the ultra-high-strength concrete-encased concrete-filled steel tube columns were increased by 74.8% and 162.7%, respectively, compared with the conventional columns. The configuration of the prestressed steel strip increased the ductility of the composite column by 28.9%–63% and increased the energy consumption performance by 160.2%–263.3%. By reducing the stirrup spacing and using prestressed steel strips, the concrete-filled steel tube core columns could be effectively confined, leading to a great enhancement in ductility, energy dissipation, stiffness and load-bearing capacity.

Performance analysis and application fields of reactive powder concrete

“…In 2018, Yang Yiting et al [9] conducted a simulation analysis of the mechanical properties of 7 steelconcrete columns under low-cycle repeated loads. The results showed that high-strength steel-concrete columns with large shear-to-span ratios, low axial compression ratios, high hoop reinforcement ratios, and high steel content tend to exhibit fuller hysteresis loops, indicating stronger ultimate deformation capacity of the specimens.…”

Eccentric Compression Performance of Core-Steel Tube with T-Shaped Steel Reinforced Concrete Column

“…To improve the mechanical performance of the outer concrete, Xu et al [25] and Dai et al [26] proposed the use of outsourcing angle steel to strengthen the concrete outside the steel tube. Yang et al [27] suggested using the prestressed steel strips to strengthen the restraint of the concrete outside the steel tube. While these methods can enhance the mechanical properties of CFCST columns, they also present certain challenges, including complexity and high costs.…”