Performance of CFRP strengthened full-scale SHS connections subjected to cyclic loading

Abstract

Square hollow section (SHS) beam–column connections are prevalent in steel structures and extensively used in high seismic risk regions due to their significant architectural and structural benefits. Rehabilitation and strengthening of SHS connections are important considerations due to the vulnerable effects of cyclic loading. Studies on the structural performance of CFRP strengthened SHS connections under large displacement cyclic loading are, however, very limited and the finite element (FE) modelling numerical approach not yet been developed. The objective of the current research is to develop a FE modelling numerical approach to simulate the cyclic response of CFRP strengthened SHS beam–column connections. The modelling techniques are validated by comparing the FE model simulated results with the authors’ experimental results. A detailed parametric study is then conducted to study the effects of the thickness of the beam and column section, moment arm, and the strengthening scheme on the cyclic performance of CFRP strengthened SHS beam–column connections. CFRP strengthened SHS beam–column connections have shown improvements in structural performance with respect to moment hysteresis response, stiffness and energy dissipation capacity. Moreover, CFRP strengthened connections showed less tendency for buckling compared to their bare counterparts. Research findings of the present study will be beneficial to restore the structural integrity of SHS beam–column connections through CFRP strengthening.