Impact resistance performance of seismic induced pre-damage G-UHPC beams

Abstract

Engineering structures may be subjected to couple effects of multiple loads under extreme conditions. As a green and high performance concrete, using geopolymer based ultra-high performance concrete (G-UHPC) would reduce CO₂ emissions and improve engineering structure’s safety under extreme conditions. This study investigated the static and pseudo-static behaviors of G-UHPC beams, with a primary focus on the impact resistance characteristics of seismic induced pre-damaged G-UHPC beams. The results indicated that G-UHPC beams pre-damage by 130 kN and below exhibit similar effects on the impact performance, whereas pre-damage by 160 kN has a more significant impact on the impact performance of G-UHPC beams and even change their failure mode. G-UHPC beams with varying levels of pre-damage due to cyclic loading exhibit similar deflection recovery under identical impact loading conditions. With increasing levels of pre-damage from cyclic loading, G-UHPC beams exhibited a slightly stronger energy absorption effect. Finally, an empirical formula has been established to predict the residual deflection of seismic induced pre-damaged G-UHPC beams subjected to impact loading, which exhibits good agreement with experimental data.