Comparative analysis of the seismic performance of ECC jacket reinforced columns with different cross-sectional forms subject to different load modes

• Published in: Structures (Oxford) Vol. 68; p. 107064
• Main Authors: Liu, Zhichen, Qu, Yiqun, Song, Yinglong, Wang, Jialing, Hu, Shijun, Li, Chunzhe, Zhang, Zuhua
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2024
• Subjects: Central column; Damage distribution; Engineered cementitious composites; Hysteretic performance; Static model analysis; Static model analysis; Engineered cementitious composites; Central column; Hysteretic performance; Damage distribution
• DOI: 10.1016/j.istruc.2024.107064
• ISSN: 2352-0124

Based on the high tensile strength and tensile strain of (engineered cementitious composites) ECC, it is applied to the weak link central columns of subway stations to enhance their seismic resilience. In this study, the effects of the column's cross-sectional shape, ECC jacket form, and the vertical gravity load and vertical dynamic load during seismic action on the hysteretic performance of the column were thoroughly analyzed. A constrained constitutive model for cementitious materials, a reinforced hysteresis constitute model, and a calculated damage factor for concrete were adopted to establish a three-dimensional refined column model with an experimentally verified error of less than 10 %. After that, the damage distribution and damage degree of the columns, as well as the changes in hysteretic performance such as hysteretic curve, skeleton curve, energy dissipation, and stiffness degradation were analyzed by the static model analysis. The results showed that the columns had higher damage levels under high frequency and high amplitude of dynamic axial compression ratio in the vertical direction compared to the constant high axial compression ratio, and the ECC jacket could effectively reduce the damage levels of the columns, but the use of the in-built ECC (IB-ECC) jacket was better than the out-sourced ECC (OS-ECC) jacket. In addition, the IB-ECC jacket did not significantly improve the peak bearing capacity of the columns, but significantly improved the ultimate bearing capacity and displacement ductility of the columns, while the OS-ECC jacket significantly improved the peak bearing capacity of the columns. The ECC jacket was also effective in slowing down the stiffness degradation of the columns. This study significantly contributes to the design strategies for enhancing the resilience of columns in subway stations.