Behavior of eccentrically loaded rectangular RC columns strengthened with cementitious grout: Experimental and theoretical analysis

Abstract

In this study, cementitious grout was employed to strengthen the eccentrically loaded RC columns, and the effects of reinforcement position, reinforcement thickness, and eccentricity on the compression behavior of strengthened columns were systematically evaluated. Comparative analyses were done on the failure modes, load-lateral deflection curves, longitudinal reinforcement strains, and cross-sectional strain distribution results. Results showed that no interfacial cracks were observed for the strengthened columns during the loading process. The bearing capacity of the strengthened columns with various test parameters was improved to diverse degrees when compared to the control group columns. In particular, the improvements in bearing capacity grew steadily as the reinforcement thickness increased, and the compressive-side strengthened columns exhibited more obvious improvements than tensile-side strengthened columns. Meanwhile, the enhancements in bearing capacity were increased as the eccentricity increased for the compressive-side strengthened columns, but they exhibited a falling trend for the tensile-side strengthened columns. Besides, calculation methods for predicting the bearing capacity and deformation of the strengthened columns were proposed by taking into account the additional eccentricity brought on by the misalignment of the section's physical and geometric centroid.