scholarly journals Direct Computation of 3-D Stress Intensity Factors of Straight and Curved Planar Cracks with the P-Version Finite Element Method and Contour Integral Method

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3949
Author(s):  
Jianming Zhang ◽  
Rui Xu ◽  
Yong He ◽  
Wensheng Yang

This paper presents direct computations of 3-D fracture parameters including stress intensity factors (SIFs) and T-stress for straight and curved planar cracks with the p-version finite element method (P-FEM) and contour integral method (CIM). No excessive singular element or enrichment function is required for the computation. To demonstrate the accuracy and efficiency of the proposed approaches, several benchmark numerical models of 3-D planar straight and curved cracks with single and mixed-mode fractures are considered and analyzed: a through thickness edge straight crack in a homogeneous material, a through thickness inclined straight crack, a penny-shaped crack embedded in a cube and a central ellipse shaped crack in a homogeneous cube. Numerical results are analyzed and compared with analytical solutions and those reported by the extended finite element method (XFEM) and the scaled boundary finite element method (SBFEM) in the available literature. Numerical experiments show the accuracy, robustness and effectiveness of the present method.

2013 ◽  
Vol 353-356 ◽  
pp. 3369-3377 ◽  
Author(s):  
Ming Guang Shi ◽  
Chong Ming Song ◽  
Hong Zhong ◽  
Yan Jie Xu ◽  
Chu Han Zhang

A coupled method between the Scaled Boundary Finite Element Method (SBFEM) and Finite Element Method (FEM) for evaluating the Stress Intensity Factors (SIFs) is presented and achieved on the platform of the commercial finite element software ABAQUS by using Python as the programming language. Automatic transformation of the finite elements around a singular point to a scaled boundary finite element subdomain is realized. This method combines the high accuracy of the SBFEM in computing the SIFs with the ability to handle material nonlinearity as well as powerful mesh generation and post processing ability of commercial FEM software. The validity and accuracy of the method is verified by analysis of several benchmark problems. The coupled algorithm shows a good converging performance, and with minimum additional treatment can be able to handle more problems that cannot be solved by either SBFEM or FEM itself. For fracture problems, it proposes an efficient way to represent stress singularity for problems with complex geometry, loading condition or certain nonlinearity.


2014 ◽  
Vol 553 ◽  
pp. 737-742
Author(s):  
Morsaleen Shehzad Chowdhury ◽  
Chong Ming Song ◽  
Wei Gao

The sensitivity of the stress intensity factors (SIFs) with respect to the crack geometry, shape sensitivity, plays an important role in the reliability analysis of cracked structures and many other fracture mechanics applications. This paper presents a numerical technique to evaluate the shape sensitivity using the scaled boundary finite element method. It combines the finite element formulations with the boundary element discretization. The crack surface remains meshless. The variation in crack geometry is modelled by applying direct differentiation with respect to the crack geometry, without remeshing. The sensitivity of the stress modes are not required for the calculation of the sensitivity of the SIFs. A numerical example demonstrates the efficiency, accuracy and simplicity of the technique.


1972 ◽  
Vol 7 (2) ◽  
pp. 125-131 ◽  
Author(s):  
J R Dixon ◽  
J S Strannigan

It is shown that the finite-element method of analysis, used in conjunction with a generalized form of the compliance equations of fracture mechanics, can provide a general means of determining energy release rates and stress-intensity factors for complex crack configuration and loadings. The method is applied to several crack configurations in flat plates and in round bars.


Sign in / Sign up

Export Citation Format

Share Document