PERFORMANCE ASSESSMENT OF RECYCLED AGGREGATE CONCRETE SHORT COLUMNS SUBJECTED TO ECCENTRIC COMPRESSION LOAD

This paper describes an experimental and analytical investigation on the static behavior of eccentrically compressed recycled aggregate concrete short columns with square cross-section. A total of 12 columns were tested under eccentric compression loading until failure. The parameters of this experiment included the recycled coarse aggregate (RCA) replacement ratio (0%, 20%, and 40%), load eccentricity ratio (0.25, 0.4) and compressive strength of concrete. The effects of these parameters on the failure behavior, ultimate load and stress - strain curves of RCA columns are discussed. The test results indicated that the eccentrically compressed specimens generally possess stable load versus deformation curves including the initial linear and the subsequent nonlinear stages before reaching the peak load and the post-peak descending stage. The load capacity of the columns increased with decreasing the load eccentricity and increasing the compressive strength of concrete. Numerical simulation of the eccentrically compressed RCA columns is also carried out by a finite element analysis (FEA) model. The models were verified by experimental results and are used to conduct a thorough parametric study on various design configurations such as longitudinal steel reinforcement ratio, transverse steel reinforcement ratio and eccentricity ratio.