Formulation and identification problems for cracked orthotropic materials
The purpose of the present paper is to identify the elastic parameters of an orthotropic material from measured displacements of crack edges. This paper consists of two parts. In the first part, the expressions for stresses and displacements for plane strain of crack edges in an orthotropic material are derived through the complex variable approach. Mode I crack problems on three mutually orthogonal planes are considered and solved in a unified form. In the second part, an iterative statistical identification method, based on Taylor expansion of experimental data in the neighbourhood of initial parameters, is used to identify the elastic constants of an orthotropic medium from the Mode I crack displacements measured from the mid-point of the crack. This method is based on a Bayesian approach. The convergence of the identified parameters and the approach of the analytical displacements to their experimental values is illustrated. Some graphics are provided to illustrate the sensitivity of the solution with the initial values parameters.
KeywordsElastic Constant Elastic Parameter Orthotropic Material Orthogonal Plane Displacement Discontinuity
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