Quasi-Static Finite Element Analysis and Damage Quantitative Evaluation of Special-Shaped Concrete-Filled Steel Tubular Column Composite Frame Structure
Creators: name: Luo, Liang
name: Xiao, Chong
name: Shan, Zhi
name: Lv, Xiaoyong
Publisher: name: Taylor & Francis
Year: 2024
Subjects: subject: Biophysics
subject: Physical Sciences not elsewhere classified
subject: Molecular Biology
subject: Physiology
subject: FOS: Biological sciences
subject: Mathematical Sciences not elsewhere classified

description: Based on the elaborate 3D solid finite element (FE) model established by ABAQUS software, a pseudo-static analysis was conducted on a special-shaped concrete-filled steel tubular column composite frame structure. The FE model considers the confinement effect of both the steel tubes and the tensile bars exerting on the core concrete. The results of the numerical analysis concerning failure modes, load-displacement hysteretic curves, load-displacement skeleton curves and stiffness degradation-displacement curves demonstrate a strong correlation with the existing quasi-static test data. Furthermore, an in-depth analysis was conducted on the impact of the axial compression ratio of column on the plastic energy dissipation distribution mechanism. With an axial compression ratio of the column ranging from 0.1 to 0.55, the composite frame structure primarily relies on the energy dissipation of beams, while the columns serve as supplementary support, thereby exemplifying the principle of “strong column-weak beam.” As the axial compression ratio rises to the range of 0.6–0.8, the composite frame structure transitions a “strong beam-weak column” structural system. Combined with the longitudinal compressive strain of the steel tube at the bottom of the column, a quantitative evaluation method for seismic damage is proposed, grounded in indexes of “stiffness damage” and “energy damage.” Then, the threshold values of energy damage and stiffness damage are determined across four distinct levels: “elastic stage in small earthquake,” “elasto-plastic stage in medium earthquake,” “plastic stage in heavy earthquake” and “failure stage.” The proposed method effectively evaluate the damage severity of special-shaped CFT column composite frame structure subjected to seismic events. The FE model in this paper has high accuracy, which can reasonably simulate the pseudo-static behavior of special-shaped CFT column composite frame structure.A seismic energy dissipation analysis method of special-shaped CFT column composite frame structure is proposed, and the influence of axial compression ratio on the energy dissipation distribution mechanism of beams and columns is further analyzed.This paper propose two indexes, namely “stiffness damage” and “energy damage,” which can reflect the internal properties of composite frame structure and can accurately evaluate the damage degree of composite frame structures. The FE model in this paper has high accuracy, which can reasonably simulate the pseudo-static behavior of special-shaped CFT column composite frame structure. A seismic energy dissipation analysis method of special-shaped CFT column composite frame structure is proposed, and the influence of axial compression ratio on the energy dissipation distribution mechanism of beams and columns is further analyzed. This paper propose two indexes, namely “stiffness damage” and “energy damage,” which can reflect the internal properties of composite frame structure and can accurately evaluate the damage degree of composite frame structures.