Fatigue life and crack path predictions in generic 2D structural components

This paper proposes a reliable and cost-effective two-phase methodology to predict crack propagation life in generic two-dimensional (2D) structural components. First, the usually curved fatigue crack path and its stress-intensity factors are calculated at small crack increments in a specialized finite-element software, using automatic remeshing algorithms, special crack tip elements and appropriate crack increment criteria. Then, the computed stress-intensity factors are transferred to a powerful general-purpose fatigue-design program, which has been designed to predict both initiation and propagation fatigue lives by means of classical design methods. Particularly, its crack propagation module accepts any KI expression and any crack growth rate model, considering sequence effects such as overload-induced crack retardation to deal with 1D and 2D crack propagation under variable amplitude loading. Non-trivial application examples compare the numerical simulation results with those measured in physical experiments. � 2002 Elsevier Science Ltd. All rights reserved.

[1]  O. Zienkiewicz,et al.  Finite element Euler computations in three dimensions , 1988 .

[2]  Túlio N. Bittencourt,et al.  AUTOMATIC FATIGUE CRACK PROPAGATION USING A SELF-ADAPTATIVE STRATEGY , 1999 .

[3]  M. German,et al.  Crack extension modeling with singular quadratic isoparametric elements , 1976 .

[4]  J. O'Rourke Art gallery theorems and algorithms , 1987 .

[5]  F. Erdogan,et al.  On the Crack Extension in Plates Under Plane Loading and Transverse Shear , 1963 .

[6]  D. Broek The practical use of fracture mechanics , 1988 .

[7]  A. Rassineux,et al.  GENERATION AND OPTIMIZATION OF TETRAHEDRAL MESHES BY ADVANCING FRONT TECHNIQUE , 1998 .

[8]  Glaucio H. Paulino,et al.  A methodology for adaptive finite element analysis: Towards an integrated computational environment , 1999 .

[9]  Robert H. Dodds,et al.  Numerical Evaluation of Domain and Contour Integrals for Nonlinear Fracture Mechanics: Formulation and Implementation Aspects , 1988 .

[10]  K. Anastasiou,et al.  AN AUTOMATIC TETRAHEDRAL MESH GENERATION SCHEME BY THE ADVANCING FRONT METHOD , 1997 .

[11]  M. Kanninen,et al.  A finite element calculation of stress intensity factors by a modified crack closure integral , 1977 .

[12]  S. Suresh Fatigue of materials , 1991 .

[13]  I. Raju Calculation of strain-energy release rates with higher order and singular finite elements , 1987 .

[14]  Paul A. Wawrzynek,et al.  Interactive finite element analysis of fracture processes: An integrated approach , 1987 .

[15]  Joaquim B. Cavalcante Neto,et al.  An Algorithm for Three-Dimensional Mesh Generation for Arbitrary Regions with Cracks , 2001, Engineering with Computers.

[16]  Joaquim B. Cavalcante Neto,et al.  An Algorithm for Three-Dimensional Mesh Generation for Arbitrary Regions with Cracks , 1999, XII Brazilian Symposium on Computer Graphics and Image Processing (Cat. No.PR00481).

[17]  S. Lo A NEW MESH GENERATION SCHEME FOR ARBITRARY PLANAR DOMAINS , 1985 .

[18]  Hussain,et al.  Strain Energy Release Rate for a Crack Under Combined Mode I and Mode II , 1974 .

[19]  Luiz Fernando Martha,et al.  Adaptive simulation of fracture processes based on spatial enumeration techniques , 1997 .

[20]  Paul A. Wawrzynek,et al.  Quasi-automatic simulation of crack propagation for 2D LEFM problems , 1996 .

[21]  Luiz Fernando Martha,et al.  Fatigue Crack Propagation under Complex Loading in Arbitrary 2D Geometries , 2002 .

[22]  Roger I. Tanner,et al.  Generation of unstructured tetrahedral meshes by advancing front technique , 1993 .

[23]  Paresh Parikh,et al.  Generation of three-dimensional unstructured grids by the advancing-front method , 1988 .

[24]  G. Sih Strain-energy-density factor applied to mixed mode crack problems , 1974 .

[25]  Pc McKeighan,et al.  Applications of automation technology in fatigue and fracture testing and analysis : fourth volume , 2002 .

[26]  D. F. Watson Computing the n-Dimensional Delaunay Tesselation with Application to Voronoi Polytopes , 1981, Comput. J..

[27]  Peter Hansbo,et al.  On advancing front mesh generation in three dimensions , 1995 .

[28]  S. Atluri,et al.  CALCULATION OF FRACTURE MECHANICS PARAMETERS FOR AN ARBITRARY THREE-DIMENSIONAL CRACK, BY THE ‘EQUIVALENT DOMAIN INTEGRAL’ METHOD , 1987 .

[29]  Silvio Valente,et al.  Experimental and Numerical Fracture Modelling of a Gravity Dam , 1994, SP-143: New Experimental Techniques for Evaluating Concrete Material & Structural Performance.

[30]  W. Elber The Significance of Fatigue Crack Closure , 1971 .