Experimental and numerical investigation of carbon textile/cementitious matrix interfacebehaviourfrom pull-out tests

Abstract

In the context of the application of textile-reinforced concrete composite (TRC) for strengthening or reinforcing of structural elements, an important factor that significantly influences its mechanical behaviour is the bond strength of the textile/cementitious matrix interface. In order to improve this bond, reinforcement textile is usually treated with different products in the manufacturing procedure. This paper presents the experimental and numerical results concerning the mechanical behaviour of carbon textile/cementitious matrix interface from the pull-out tests. The carbon textile was treated with an amorphous silica product to improve the bond with the cementitious matrix and embedded in the cementitious matrix with different lengths. The experimental results showed that all pull-out tests gave typical “force – slip” curves of interface behaviour as shown in the literature with three phases: perfect bonding phase, debonding phase, and pure friction phase. The effects of carbon textile and embedded length on pull-out behaviour and failure mode of textile/matrix interface specimens could be found and analyzed. Concerning the mesoscale modeling work, the numerical model was developed and validated by using a nonlinear spring model for interface behaviour and taking into account the crack damage of the cementitious matrix in the calculation. The numerical results highlighted that the numerical model could predict the relationship of pull-out force and slip for all cases of the embedded length of carbon textiles within the cementitious matrix. This paper shows that both experimental and numerical results on the carbon textile/cementitious matrix interface has a good agreement in pull-out behaviour and failure mode.