Assessment of structural performance of HSC slender columns via experimental tests and numerical analysis

The paper presents the results from an experimental investigation and numerical analyses on the behaviour of high strength concrete slender columns. Eight slender columns with square sections of little size were tested under monotonic eccentric compressive loading. Main variables of tests were the concrete strength and the axial load eccentricity. Four different concrete mixes with cylindrical compressive strengths from 60 to 100 MPa and two different load eccentricities were considered. Results from tests revealed a significant increase in load capacity with increased concrete strength as well as demonstrated that HSC columns collapse in a more brittle manner than NSC columns. A finite-element nonlinear model was developed to reproduce the behaviour of the columns up to failure and to investigate the role of different geometrical and material parameters. Overall, this study shows that the numerical model well predicts main results from tests; however, numerical analyses also revealed that the load capacity is very sensitive to geometrical uncertainties, probably due to the small dimensions of the columns.