# A Comparative Analysis of 3D Software for Modeling Fatigue Crack Growth: A Review
## 2 Software
### Numerical-Based Approaches
#### 2.1.1 ABAQUS  
ABAQUS is a widely used commercial finite element analysis software package that offers powerful capabilities for modeling fatigue crack growth. It provides a comprehensive set of tools and features for simulating and analyzing various engineering problems, including fatigue crack growth in structures [8; 9; 10]. To incorporate the Extended Finite Element Method (XFEM) into ABAQUS, users can utilize a User Subroutine. This subroutine allows for the implementation and integration of XFEM functionalities into the software [11; 12; 13; 14; 15]. ABAQUS allows users to create complex 3D models using its intuitive graphical user interface (GUI) or by importing CAD files. The geometry should include the cracked region and any other relevant features. ABAQUS provides meshing tools to generate a finite element mesh for the model geometry. In ABAQUS, there are different types of meshing techniques available for discretizing the geometry of a model. These include structured, unstructured, hybrid, adaptive, mesh-to-mesh contact, and cohesive zone elements. The choice of mesh type depends on the complexity of the geometry and the specific analysis requirements. The mesh should be refined around the crack region to capture the crack propagation accurately. Different element types and mesh densities can be selected based on the specific requirements of the analysis. ABAQUS is known for its computational efficiency and robustness in modeling fatigue crack growth. The software utilizes advanced numerical techniques, such as adaptive meshing and parallel processing, to enhance the efficiency and accuracy of the analysis. ABAQUS also offers various element formulations and integration schemes that can be tailored to specific crack growth problems to reduce computational costs. Moreover, ABAQUS provides a comprehensive material library that includes fatigue data for a wide range of materials, allowing users to select appropriate material properties and fatigue models for accurate crack growth predictions. Additionally, ABAQUS supports scripting and automation capabilities, allowing users to streamline repetitive tasks and perform parametric studies efficiently. Furthermore, ABAQUS supports a variety of material failure criteria, such as fracture mechanics-based criteria (e.g., stress intensity factors) and damage-based criteria (e.g., cohesive zone modeling). In the framework of Linear Elastic Fracture Mechanics, ABAQUS employs the following crack growth criteria [16]:  
* Maximum Tangential Stress (MTS) Criterion: This criterion focuses on evaluating the maximum tangential stress acting on the crack tip. It serves as an indicator for assessing crack growth behavior under various loading conditions. By monitoring the magnitude of the tangential stress, the MTS criterion helps to predict crack propagation. * Maximum Shear Stress Ratio (MSSR) Criterion: The MSSR criterion considers the ratio between the maximum shear stress and the normal stress acting on the crackplane. This criterion provides valuable insights into crack behavior and stability. By examining the relationship between shear and normal stresses, it aids in understanding the crack growth mechanism. * Extension of the Maximum Tangential Stress (Ex-MTS) Criterion: The Ex-MTS criterion expands upon the MTS concept by incorporating additional factors that influence crack growth. It takes into account parameters such as stress intensity factors and crack path. By considering these factors, the Ex-MTS criterion enhances the accuracy of crack growth predictions. The literature extensively documents the use of ABAQUS software for fatigue crack growth modeling, with numerous studies discussing its strengths and limitations in this field. Notably, [PERSON] [9] and [PERSON] [17] developed plug-ins specifically for ABAQUS to simulate fatigue crack growth. [PERSON]'s plug-in primarily focuses on 2D analyses, while [PERSON]'s plug-in focuses on adhesively bonded joints.