Scale relationships of concrete columns

The behavior of reinforced concrete columns subjected to shear and axial force reversals were examined and compared to the behavior of small scale models. Two large scale columns were tested with a ratio of shear to axial force equal to 0.25 to simulate the loading on an exterior base story column in a slender multistory building subjected to lateral loads. Loads were applied slowly according to a pattern of reversals representative of what would occur during a strong earthquake motion. In addition, a sustained axial force was applied to each specimen which represented gravity loading. This axial force was varied for the two specimens to examine differences in behavior attributable to inconsistent modeling of gravitational accelerations. With the use of a numerical model, response of the large scale specimens was compared with measured response of small scale (approximately one twelfth scale) models which were tested.