SEISMIC PERFORMANCE ANALYSIS OF CARBON FIBER REINFORCED FRAME STRUCTURE BASED ON PUSHOVER ANALYSIS METHOD

A building was chosen to conduct pushover analysis in order to study the effect of carbon fiber reinforced polymer (CFRP) on the seismic behavior of concrete frame structures. Two CFRP reinforcement schemes were designed for an existing eight-story frame structure office building in accordance with China's "Code for Design of Concrete Structure Reinforcement (GB 50367-2013)." One was local seismic reinforcement, the other was integral seismic reinforcement. The finite element analysis software is used to establish the common frame structure and the structural model under two different reinforcement schemes, and modal analysis and pushover analysis were carried out on the three models respectively. From the aspects of stiffness variation and displacement response of the structure, the seismic beharior before and after structural reinforcement was evaluated. It was found that the self-vibration frequency of the structure increased after reinforcement, which indicates that the CFRP could enhance the stiffness of the structure to some extent, but the first three main mode frequencies only increased less than 5%; Under the same deformation, the base shear force of scheme 1 increased by 24.5% compared with the initial structure, and the base shear force of scheme 2 increased by 30.4%, indicating that the structure can withstand greater deformation after CFRP reinforcement, so the ductihty is greatly improved. The floor displacement and story drift angle showed decreasing trends, the maximum story drift angle of the first scheme was reduced by 3.8%, the maximum story drift angle of the second scheme was reduced by 20%. The analysis showed that CFRP could effectively improve the seismic behavior of concrete frame structure, and the core performance was the improvement of ductility of the structure; in order to ensure the safety of the structure, the structure should be reinforced integrally.