Ultra-high performance concrete and high-strength steel: compressive behavior of concrete-encased cellular steel columns with spiral confinement

作者：Longkang Xu, Yong Yang, Bing Li, Ning Hao, Shuchen Zhang, Yicong Xue, Yi Sun · 发表于：Construction and Building Materials · 年份：2025 · DOI：10.1016/j.conbuildmat.2025.144360 · 被引用次数：3 · 研究领域：Structural Load-Bearing Analysis、Seismic Performance and Analysis、Fire effects on concrete materials

The compressive behavior of advanced ultra-high performance concrete-encased Q690 cellular steel columns (UHCES) with high-strength spiral stirrups was examined through experimental and numerical methods. Eight columns were tested under axial compression, revealing the significant influence of stirrup design and expansion ratio of steel on failure modes, load-carrying capacity, deformation capacity, stiffness, and damage progression. A finite element model was developed to simulate the axial compression behavior of UHCES columns and was validated against experimental results. An analytical model for assessing the axial compressive carrying capacity of UHCES columns was developed by integrating the confinement effects of spiral stirrups and cellular H-shaped steel columns. The contribution to the axial compressive carrying capacity of the cellular H-shaped steel columns and confined concrete were accurately calculated. Experimental results indicated that UHCES columns with bi-directional spiral stirrups exhibited superior axial compression performance compared to those with conventional rectangular stirrups, with increases of 13.4 % in load-carrying capacity, 14.5 % in stiffness, and a remarkable 209 % in deformation coefficient. Reducing stirrup spacing significantly increased the load-carrying capacity, stiffness, and deformation capacity of UHCES columns. While the load-carrying capacity, stiffness and deformation capacity initially increased with the expansion ratio of ste...