Structural identifiability of parameters of Anand material model

Area of Science:

• Computational Mechanics
• Materials Science
• Non-linear Dynamics

Background:

• Structural identifiability is crucial for parameter estimation in complex physical models.
• Non-linear material models, like the Anand model, often present challenges in parameter determination.
• Accurate parameter identification is essential for reliable material behavior prediction.

Purpose of the Study:

• To develop and validate a procedure for assessing the structural identifiability of parameters in non-linear physical models.
• Specifically, to determine the unique parameter set for the Anand material model under tensile loading.
• To introduce an innovative numerical method for parameter reduction and analysis.

Main Methods:

• A two-step procedure involving local parameter analysis and global structural dependence evaluation.
• A numerical approach that systematically reduces parameter count by substituting parameters with constant values.
• Finite element method simulations of a simplified tensile test using the Anand material model.

Main Results:

• Identification of independent parameters for the Anand material model.
• Validation of the reduced parameter set against experimental tensile test data.
• Demonstration of a high probability for unique parameter value determination using the proposed method.

Conclusions:

• The proposed method effectively assesses structural identifiability for non-linear material models.
• A reduced parameter set enhances the uniqueness of parameter values obtained from tensile tests for the Anand model.
• The approach offers an efficient and reliable way to identify critical material model parameters.