WANG Q, HU Z J, ZHU W X, et al．Study on seismic damage model of prefabricated columns reinforced with prestressed CFRP subjected to severe earthquake damage[J]. Journal of Henan Polytechnic University( Natural Science) ， doi: 10.16186/j.cnki.1673-9787. （ 2024030049  ）..

doi: 10.16186/j.cnki.1673-9787. （ 2024030049 ）..

Received： 2023-12-22

Revised： 2024-01-20

Online： 2026-06-05

Study on seismic damage model of prefabricated columns reinforced with prestressed CFRP subjected to severe earthquake damage (Online)

WANG Qiang1,2 , HU Zhaojie2, ZHU Wanxu1,2 , LU Chunling1,2

1.Guangxi Key Laboratory of Green Building Materials and Construction Industrialization, Guilin University of Technology, Guilin 541004, Guangxi, China；2. School of Civil Engineering, Guilin University of Technology, Guilin 541004, Guangxi, China

Abstract: Objectives To quantitatively assess the damage state of buildings experiencing secondary seismic damage after emergency repairs under seismic actions, Methods four prefabricated steel-reinforced concrete square columns were designed as variables based on the axial compression ratio and longitudinal bar diameter.Initially, cyclic reciprocating load tests were conducted to simulate reaching a severe seismic damage state. Subsequently, the pre-damaged columns were chiseled to remove surface concrete and were repaired and reinforced with prestressed carbon fiber-reinforced polymer (CFRP) and high-strength grout for severe seismic damage. Results By integrating existing theoretical models and experimental results, a dual-parameter seismic damage model suitable for prefabricated columns reinforced with prestressed CFRP and high-strength grouting under severe seismic damage conditions was proposed. Nonlinear regression analysis was carried out on the main design parameters of the specimens to derive the expression for combination coefficients, followed by damage quantification analysis based on the improved model and the extent of damage to the specimens. Conclusions The research indicates that an increase in one parameter under the same longitudinal bar diameter or axial compression ratio leads to a decrease in the damage index. Existing damage models generally yield damage indices greater than 1 or less than 0.8 when calculating the failure of repaired columns, failing to adequately capture the variations in damage indices, which do not meet the threshold values for severe seismic damage. In contrast, the revised damage model in this study calculates damage indices between 0.8 and 1.0, better reflecting the damage evolution of severely earthquake-damaged components repaired with prestressed CFRP. Based on the improved model and experimental results, five damage levels were redefined, each assigned with specific damage index threshold values.

Key words: prefabricated columns; prestressed CFRP fabric; seismic damage repair; initial damage; seismic damage model