Computational design of multiaxial tests for anisotropic material characterization

Although anisotropic materials provide more capabilities for mission- and application-tailored design and functional flexibility to final structures than regular isotropic materials, the directional behavior of the anisotropic materials further complicates their inelastic and damage behavior. Such a non-linear behavior can be effectively observed and characterized by multiaxial testing, but how to design a multiaxial test for material characterization given a specimen remains an untouched issue. This paper presents a methodology that numerically designs the loading path of a multiaxial testing machine to characterize anisotropic materials. The multiaxial test must be able to exhibit quantities used to characterize materials as distinctly as possible. The proposed methodology formulates distinguishability and uniqueness as such quantities by first analyzing the specimen on a continuum basis with finite element method and then applying singular value decomposition. Associating the distinguishability and uniqueness with the informativeness of the loading path, the design problem is formulated such that an effective loading path can be found efficiently by a standard optimization method. Numerical examples first investigate the validity of the distinguishability and the uniqueness as performance measures to evaluate loading paths. The efficacy of the proposed methodology has been then confirmed by analyzing it with and applying it to design problems.

[1]  J. Vantomme,et al.  A comparison between static and dynamic inverse modelling for the identification of orthotropic elastic material parameters , 2005 .

[2]  Genki Yagawa,et al.  Implicit constitutive modelling for viscoplasticity using neural networks , 1998 .

[3]  John G. Michopoulos,et al.  Experimental Determination of Dissipated Energy Density as a Measure of Strain-Induced Damage in Composites , 1992 .

[4]  Frederick E. Petry,et al.  Principles and Applications , 1997 .

[5]  C. Key,et al.  Comparison of MCT Failure Prediction Techniques and Experimental Verification for Biaxially Loaded Glass Fabric-reinforced Composite Laminates , 2004 .

[6]  Tomonari Furukawa,et al.  Parameter identification with weightless regularization , 2001 .

[7]  V. A. Morozov,et al.  Methods for Solving Incorrectly Posed Problems , 1984 .

[8]  John G. Michopoulos,et al.  Characterization of strain-induced damage in composites based on the dissipated energy density part I. Basic scheme and formulation , 1995 .

[9]  Per Christian Hansen,et al.  Analysis of Discrete Ill-Posed Problems by Means of the L-Curve , 1992, SIAM Rev..

[10]  Shad M. Sargand,et al.  DETERMINATION OF HYPERBOLIC SOIL MODEL PARAMETERS FOR SAND USING A MULTIAXIAL DEVICE. NUMERICAL MODELS IN GEOMECHANICS. NUMOG III. PROCEEDINGS OF THE 3RD INTERNATIONAL SYMPOSIUM HELD AT NIAGARA FALLS, CANADA, 8-11 MAY 1989 , 1989 .

[11]  D. Adams,et al.  Development of a True Triaxial Testing Facility for Composite Materials , 2000 .

[12]  D. F. Adams,et al.  Development of an electromechanical triaxial test facility for composite materials , 2000 .

[13]  Leif A. Carlsson,et al.  Experimental characterization of advanced composite materials , 1987 .

[14]  T. Furukawa,et al.  Implicit material modeling for temperature-dependent viscoplaticity using multi-layer neural networks , 2003 .

[15]  Kenneth Reifsnider,et al.  Stiffness-reduction mechanisms in composite laminates , 1982 .

[16]  S. Tsai,et al.  On the Behavior of Composite Laminates After Initial Failures , 1974 .

[17]  Peter J. Bonacuse,et al.  Multiaxial fatigue and deformation : testing and prediction , 2000 .

[18]  C. W. Groetsch,et al.  The theory of Tikhonov regularization for Fredholm equations of the first kind , 1984 .

[19]  A. Kelly,et al.  Theory of multiple fracture of fibrous composites , 1973 .