Abstract: In order to study the fire resistance performance of the flange plate strengthened beam-column joints with flange-reinforced plate after an earthquake, this paper used the finite element software ANSYS was utilized to establish the computational calculation model, and the calculation results were compared with the existing test results to verify the accuracy and efficacy effectiveness of the calculation model.The pushover method was employedused to simulate the seismic damage under different earthquake levels by introducing damage variables D. The residual stress and deformation caused by earthquake were transferred to the heating process by restart analysis method. The fire resistance, ultimate displacement and failure mechanism of flange beam-column joints with flange flange-strengthened beams under different parameters and damage variables were analyzed. The results showed that the damage variable had a major effect on the fire resistance of flange plate plate-strengthened beam-column joints. With the increase of damage variable D, the critical temperature of each connection was decreased greatly. Increasing the parameter α and γ can enhance the fire resistance of flange plate strengthened beam-column joints. While the increase of the β can impair the fire resistance of flange plate plate-strengthened beam-column joints.

Key words: post-earthquake fire, flange plate plate-strengthened beam flange, beam-column joints, damage variable, fire resistance