12. Determination of Constitutive Properties in Inverse Problem Using Airy Stress Function

A new inverse problem formulation is developed using the Airy stress function. Inverse methods are used to determine the constitutive properties of a graphite/epoxy laminated composite loaded vertically by processing measured values of v-displacement component with an Airy stress function in complex variables. Displacements are recorded using digital image correlation. The traction-free conditions on the symmetrically located sided notches are satisfied analytically using conformal mappings and analytic continuation. The traction-free on the vertical free edge and a symmetrical condition on horizontal line of symmetry are imposed discretely. The primary advantage of this new formulation is the direct use of displacement data, eliminating the need for numerical differentiation when strain data is required. The inverse method algorithm determined the constitutive properties with errors range from 2% to 10%. Selection of Airy coefficients, test geometry configuration and comparison with other inverse methods will be addressed.