Behavior of Short Columns Constructed using Engineered Cementitious Composites under Seismic Loads

Abstract

The present research reports the application of engineered cementitious composites (ECC) as an alternative to conventional concrete to improve the brittle shear behavior of short columns. Experimental and finite element investigation was conducted by testing five reinforced engineered cementitious composite (RECC) concrete columns (half-scale specimens) and one control reinforced concrete (RC) specimen for different shear-span and transverse reinforcement ratios under cyclic lateral loads. RECC specimens with higher shear-span and transverse reinforcement ratios demonstrated a significant effect on the column shear behavior by improving ductility (>5), energy dissipation capacity (1.2 to 4.1 times RC specimen), gradual strength degradation (ultimate drift >3.4%), and altering the failure mode. The self-confinement effect of ECC fibers maintained the integrity in the post-peak region and reserved the transmission of stress through fibers without noticeable degradation in strength. Finite element modelling of RECC specimens was carried out by adopting simplified constitutive material models. It was apprehended that the model simulated the global response (strength and stiffness) with an accuracy of about 95%, and captured the shear and flexure crack patterns reasonably well.