Estimation of crack-tip-opening displacement and crack extension of glass fiber reinforced polymer mortars using digital image correlation method

Knowledge of crack-tip-opening displacement (CTOD) has a great importance for fracture criteria that are applied to numerous structural applications. The purpose of this paper is to investigate fracture behavior of chopped glass fiber reinforced polymer mortars evaluating the CTOD values and the crack extension by means of non-contact measurement method. Furthermore, the critical stress intensity factor (K-Ic) and the critical crack-tip opening displacement (CTODc) are estimated. In order to do this, fracture test using a single-edge-cracked three-point bend specimens is performed. The experimental procedure is carried out using digital image correlation (DIC) method, which is a powerful optical-numerical method developed to determine displacement fields. These results are compared with K-Ic and CTODc achieved through Two Parameter Model (TPM) method. Overall, there is agreement between the two methods. By results, the fracture resistance to crack propagation of polymer mortars increases with the addition of glass fiber. (C) 2011 Elsevier Ltd. All rights reserved.