Study on stress-strain relationship of concrete confined with textile reinforced concrete composites

In order to study the confinement performance of concrete columns strengthened with textile reinforced concrete (TRC), 13 concrete column specimens, including 10 column specimens strengthened with TRC and 3 control column specimens, were tested under axial load, and the influences of the number of textile layers, chopped fiber sand and concrete strength on reinforcement effects of TRC were analyzed. Based on experimental results, the simplified calculation model for the stress-strain relationship of TRC confined concrete columns was proposed. The results indicate that the failure mode of concrete column strengthened with TRC under axial load has been improved. Compared with the unstrengthened columns, the bearing capacity and deformation capacity of columns strengthened with TRC are improved, and the extent of improvement is related to the number of textile layers, concrete strength and the incorporation of chopped fibers. The bearing capacity and ductility of the strengthened column exhibit more increment with more increase of textile layers and less strength of concrete, and the maximum increasement can be up to 67.3% and 65.2%, respectively. The bearing capacity and ductility of strengthened columns are improved with the incorporation of chopped fibers into TRC matrix. In addition, the proposed stress-strain relationship models can be used to describe the stress-strain relationship of TRC confined concrete columns well, and the predicted results are in good agreement with the experimental results. © 2021, Editorial Office of Journal of Building Structures. All right reserved.