Experimental and numerical investigation on axial compression of reinforced concrete columns made from recycled coarse and fine aggregates

The current study is part of a larger project called RECYBETON developed in France since 2012. This part of project deals with the important properties of hardened concrete of recycled aggregates (RA), from microstructure to properties related to durability and fire behavior. The founding objective of the RECYBETON project is generally not to formulate concrete with a given recycling rate, but rather to optimize the recycling rate so that the benefit, whether economic or environmental, is maximized. This study describes a test campaign performed on reinforced concrete (RC) columns with different recycled aggregate ratios and a reference column made of natural aggregates. An eccentric compression‐loading device was developed to test the columns and determine the effects of small and high‐replacement ratios of recycled coarse and fine aggregates on the compression behavior of RC column. This required evaluating the mechanical behavior in compression and tension of the different materials (mechanical behavior of the various concretes according to their recycled aggregate ratios and the mechanical behavior of the steel). Finite element (FE) models were developed using Abaqus software and their performance validated based on experimental results of columns subjected monotonic loading to failure. The fracture mode was obtained by the finite element method, while the loads, displacements, and deformations of the steels and the concrete were studied and compared to the physical tests. Consistent results were obtained from the numerical and experimental tests.