Compressive Behavior of Normal Strength Concrete Column Strengthened With Reinforced Ultra-High-Performance Concrete

Ultra-high-performance concrete (UHPC) and normal strength concrete (NSC) are concrete materials with high compatibility characteristics.This paper presents the experimental and numerical study on the uniaxial compression behavior of NSC columns strengthened using UHPC.The main idea of the proposed strengthening technique is to optimize the UHPC and enhance the ultimate capacity, impermeability, and crack resistance of the damaged column.Fourteen ( 14) NSC columns strengthened with UHPC were tested.The influence of longitudinal groove geometry and volumetric ratio of shear reinforcement on the failure mode, ultimate capacity, displacement, initial stiffness, ductility index, and ultimate strain of the composite column was investigated.Increasing the groove size will increase the axial resistance and improve the ductility of the strengthened NSC column.Decreasing the shear reinforcement ratio does not affect the axial strength of the column.The developed FEM can accurately simulate the behavior of the column strengthened with UHPC using the proposed technique.