Tang Chong, Bao Yanhong, Yu Yang
Department of Civil Engineering and Water Resources, Qinghai University, Xining 810016, China.
Centre for Infrastructure Engineering, Western Sydney University, Sydney 2000, Australia.
Materials (Basel). 2025 Apr 26;18(9):1975. doi: 10.3390/ma18091975.
To investigate the seismic performance of steel tube-reinforced concrete (ST-RC) columns after fire on one side, this study employs numerical simulation and theoretical analysis methods. A numerical analysis model of ST-RC columns post-fire is established using ABAQUS to simulate and analyze their seismic performance under cyclic loading. The characteristics of the hysteresis curves of ST-RC columns after fire on one side under cyclic loading are described in detail. Comparisons are made between the skeleton curves, ductility, stiffness degradation, and energy dissipation capacity of ST-RC columns under three conditions: unexposed to fire, exposed to fire on all sides, and exposed to fire on one side. Finally, multiple influencing factors, including heating time, slenderness ratio, section size, core area ratio, external concrete strength, reinforcement ratio, and load ratio, are selected for parametric analysis of the ductility coefficient, stiffness, and viscous damping coefficient. Mathematical formulas for the ductility coefficient, stiffness, and viscous damping coefficient of ST-RC columns after fire on one side under cyclic loading are derived through regression analysis. The results show that the seismic performance of ST-RC columns is attenuated after fire on one side, and the ductility and initial stiffness of ST-RC columns decreases by 5.62% and 24.69%, respectively, compared with those without fire. The energy dissipation capacity of the ST-RC column increases significantly when it enters the plastic deformation stage under the action of reciprocating load.
为研究单侧受火后钢管混凝土（ST-RC）柱的抗震性能，本研究采用数值模拟和理论分析方法。利用ABAQUS建立单侧受火后ST-RC柱的数值分析模型，以模拟和分析其在循环加载下的抗震性能。详细描述了单侧受火后ST-RC柱在循环加载下的滞回曲线特征。对ST-RC柱在未受火、四面受火和单侧受火三种工况下的骨架曲线、延性、刚度退化和耗能能力进行了比较。最后，选取加热时间、长细比、截面尺寸、核心面积比、外部混凝土强度、配筋率和荷载比等多个影响因素，对延性系数、刚度和黏滞阻尼系数进行参数分析。通过回归分析得出了单侧受火后ST-RC柱在循环加载下的延性系数、刚度和黏滞阻尼系数的数学公式。结果表明，单侧受火后ST-RC柱的抗震性能有所衰减，与未受火的ST-RC柱相比，其延性和初始刚度分别降低了5.62%和24.69%。在往复荷载作用下，ST-RC柱进入塑性变形阶段时耗能能力显著提高。
