Application of Fe-SMA plates for enhancing post-earthquake fire resistance in beam-column connections: A feasibility study

This paper presents a comprehensive review of contemporary research concerning post-earthquake fire scenarios, underscoring the urgent necessity for improvements in post-earthquake fire resistance at the structural level. In view of the prevalent utilization of steel structures that exhibit superior seismic performance yet inadequate fire resistance, this study investigates the feasibility of employing a novel iron-based shape memory alloy (Fe-SMA) plate to enhance the post-earthquake fire resistance of steel beam-column connections. The seismic performance and post-earthquake fire resistance of the connection were evaluated through validated finite element simulations with test results. The findings indicate that the connection exhibits outstanding seismic performance under quasi-static loading conditions. Notably, the ultimate bearing capacity of the connection at ambient temperature surpasses that of the conventional Q235 model by 25.6%, with a 17% reduction in residual deformation and a 9% increase in energy dissipation. At elevated temperatures of 400 °C–600 °C, the employment of Fe-SMA significantly mitigates the degradation in bearing capacity of the connections in fire, exhibiting a reduction of bearing capacity degradation at 45%–441%. Furthermore, the steady-state loading strength at 400 °C–600 °C of the connection is found to be 12.6%–89.9% higher than that of the Q235 model, markedly improving the post-earthquake fire resistance of the connection.