Research on mechanical properties and failure mechanism of TRM composites via digital image correlation method and finite element simulation

The purpose of this paper is to study tensile properties and interfacial bonding properties of textile reinforced mortar composites (TRM) widely used for externally strengthening damaged buildings. Based on the digital image correlation (DIC) method and finite element (FE) simulation, the tensile and interfacial shear test results of steel fiber textile and carbon fiber textile reinforced mortar composites were analyzed. First, DIC was used to detect the crack onset and propagation of the specimen during the tensile process. The concept of gradient interface was introduced to improve the bonding performance. The effects of the hydration degree of mortar, and reinforcing textile type on interfacial bonding properties were then evaluated through double-lap shear testing. Last, the stress distribution and load transfer during textile pull-out from the mortar were analyzed based on FE simulation with the bond-slip law extracted from the double-lap shear experiment.