Shear test of the rectangular beam on the new to old concrete interface based on Digital Image Correlation

Abstract

The bond property of new to old concrete is the key to strengthen and reinforce the hydraulic concrete structure, and shear strength is an important index of its bond property. With the help of advanced Digital Image Correlation (DIC), the direct shear state, fracture surface displacement, deformation and crack location of the new to old concrete bonding interface are studied through the shear test of rectangular beam, the strain distribution pattern of the bonding interface is well obtained. The results show that the interfacial roughness of specimen has great influence on the shear strength of the repaired specimen. The greater the roughness is, the better the bond property is. Due to friction, the specimen itself will be subject to the combined action of bending and shearing, which leads to bending shear failure of specimen rather than pure shear failure.