Fully Automated Mixed Mode Crack Propagation Analyses Using VCCM (Virtual Crack Closure-Integral Method) for Tetrahedral Finite Element

The authors have been developing a crack propagation analysis system that can deal with arbitrary shaped cracks in three-dimensional solids. The system is consisting of mesh generation software, a large-scale finite element analysis program and a fracture mechanics module. To evaluate the stress intensity factors, a Virtual Crack Closure-Integral Method (VCCM) for the second-order tetrahedral finite element is adopted and is included in the fracture mechanics module. The rate and direction of crack propagation are predicted using appropriate formulae based on the stress intensity factors.

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Development of the Next-Generation Computational Fracture Mechanics Simulator on the Earth Simulator 2

Volume 2: 32nd Computers and Information in Engineering Conference, Parts A and B ◽

10.1115/detc2012-70909 ◽

2012 ◽

Cited By ~ 1

Author(s):

Kaworu Yodo ◽

Hiroshi Kawai ◽

Hiroshi Okada ◽

Masao Ogino ◽

Ryuji Shioya

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Stress Intensity ◽

Fracture Mechanics ◽

Large Scale ◽

Three Dimensional ◽

Intensity Factors ◽

Element Analysis ◽

Mechanics Analysis ◽

Analysis System

Fracture mechanics analysis using the finite element method has been one of the key methodologies to evaluate structural integrity for aging infrastructures such as aircraft, ship, power plants, etc. However, three-dimensional crack analyses for structures with highly complex three-dimensional shapes have not widely been used, because of many technical difficulties such as the lack of enough computational power. The authors have been developing a fracture mechanics analysis system that can deal with arbitrary shaped cracks in three-dimensional structures. The system consists of mesh generation software, a finite element analysis program and a fracture mechanics module. In our system, a Virtual Crack Closure-Integral Method (VCCM) for the quadratic tetrahedral finite elements is adopted to evaluate the stress intensity factors. This system can perform the three-dimensional fracture analyses. Fatigue and SCC crack propagation analyses with more than one cracks of arbitrary complicated shapes and orientations. The rate and direction of crack propagation are predicted by using appropriate formulae based on the stress intensity factors. When the fracture mechanics analysis system is applied to the complex shaped aging structures with the cracks which are modeled explicitly, the size of finite element analysis tends to be very large. Therefore, a large scale parallel structural analysis code is required. We also have been developing an open-source CAE system, ADVENTURE. It is based on the hierarchical domain decomposition method (HDDM) with the balancing domain decomposition (BDD) pre-conditioner. A general-purpose parallel structural analysis solver, ADVENTURE_Solid is one of the solver modules of the ADVENTURE system. In this paper, we combined VCCM for the tetrahedral finite element with ADVENTURE system and large-scale fracture analyses are fully automated. They are performed using the massively parallel super computer ES2 (Earth Simulator 2) which is owned and run by JAMSTEC (Japan Agency for Marine-Earth Science and Technology).

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On the Crack Propagation Trajectory of Central Cracked Plates under Mixed Mode Loading Conditions

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.462-463.154 ◽

2011 ◽

Vol 462-463 ◽

pp. 154-159

Author(s):

Miloud Souiyah ◽

Andanastuti Muchtar ◽

Ahmad Kamal Ariffin

Keyword(s):

Finite Element ◽

Stress Intensity ◽

Crack Propagation ◽

Stress Intensity Factors ◽

Mixed Mode ◽

Loading Conditions ◽

Intensity Factors ◽

Element Analysis ◽

Cracked Plates ◽

Fortran Language

A Finite Element (FE) programme for crack propagation was developed by using a source code written in the FORTRAN language to evaluate the Stress Intensity Factors (SIFs) and to predict the crack propagation trajectory. In this study, a Central Cracked Plate (CCP) with two holes under mixed mode (I & II) loading conditions is considered. Finite Element Analysis (FEA) combined with the concepts of Linear Elastic Fracture Mechanics (LEFM) provides a practical and convenient means to study the fracture and crack growth of the solid materials. The Displacement Extrapolation Technique (DET) is performed on this work in order to compute the stress intensity factors (SIFs) during the crack propagation. Additionally, to validate the capability and the reliability of this developed FE programme, the results of the current study are compared with experimental results from the literature.

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