Understanding failure and stress-strain behavior of very-high strength concrete (>100 MPa) confined by lateral reinforcement

An experimental program is carried out to evaluate the stress-strain behaviour and investigate the failure mechanisms of confined very-high strength concrete (VHSC) with compressive strengths of up to 160 MPa and lower confinement pressures in the range of 0.6-2.7 MPa. Even though post-peak behaviour of concrete is explained and modelled using the confinement effects, the study proposes that it can be explained by superposition of the shear strength behaviour at the failure plane of concrete, confinement effect, and dowelling action of steel. The stress-strain behaviour is further explained through a theoretical approach and it has good agreement with the experimental results.