## 1 Introduction  
Several studies are being conducted on composite materials to design structures in engineering. In addition to aeronautical fields that have been investigated extensively, studies are being performed in a variety of fields such as the automobile and naval manufacturing industries. In structural design, geometric discontinuities, such as holes and notches, should be studied. Discontinuities in materials can serve as advantages in areas such as sound scattering [1]. However, they can also pose critical issues as they can cause stress concentrations in structural design and determine the overall structural life. Furthermore, in designing structures using composite materials, it is important to verify and predict the failure behavior of a composite material with its complexity. Progressive failure analysis (PFA) has been studied for a long time and is a prominent tool used to predict the failure of composite materials. Various studies have been conducted to investigate the failure behavior of composite materials using PFA. The Matzenmiller-Lubliner-Taylor (MLT) damage variable [2] is currently being used as a typical PFA tool. Furthermore, PFA models have been proposed in many studies. Various studies on the application of these suggested models in the design of composite structures have been conducted. [PERSON] et al. [3] studied the progressive failure behavior of notched T300/1034C graphite/epoxy composite laminate. Stress and failure analysis studies were conducted, and it was confirmed that the suggested PFA model demonstrated a good correlation with the experimental results. This model used the damage variables while taking into consideration the reduction in area induced during the failure. [PERSON] et al. [4; 5] performed an open-hole compression test using a composite laminate. Furthermore, the size effect of open-hole compressive tests was investigated. Using the crack band model, a PFA tool was developed. Additional cohesive elements were introduced using the finite element method (FEM) model to observe the delamination behavior. A PFA model using the crack band model [6] was suggested to alleviate the mesh dependency of the result. [PERSON] et al. [7] suggested a PFA model using the crack band model. The suggested model demonstrated good mesh independency and predicted the failure behavior of the notched composite laminate. Some studies pertaining to viscosity factors for FEM efficiency were conducted. [PERSON] et al. [8] used a crack-band-model-applied PFA model to predict the failure behavior of stiffened composite panels. The applied PFA model predicted the failure behavior of composite panels well and demonstrated less mesh dependency. The less mesh dependency of the crack-band-model-applied PFA model can be easily used to predict the failure behavior of complex composite structures. [PERSON] et al. [9] suggested the PFA model using the Puck failure criterion. The model used instantaneous softening behavior during the PFA. Element weakening and constant stress exposure methods were introduced in the PFA model. In comparison to the open-hole tensile test and digital image correlation (DIC) results, the efficiency of the suggested model was verified. This model effectively predicted the failure behavior of the composite laminate regardless of the stacking sequences. The failure behavior of the T300/1034C carbon/epoxy composite laminate was also studied using this model. Strain fields obtained from DIC results of the composite material were also investigated. Using DIC, [PERSON] et al. [10] measured the J-integral value of dental ceramics. The obtained strain values using DIC were used to measure the J-integral value according to Paris' equation. To verify the path independency of the J-integral, some studies were performed using various contour sizes. [PERSON] et al. [11] conducted a similar study on the composite laminate.