The in-plane elastic constants of orthotropic composite materials need to be determined in order to perform stress analysis and design of composite structures. Several specimen configurations have been proposed and the majority suffer from one of two drawbacks: either multiple specimens are required or the experimental method involves a scientific rather than an engineering approach. In the present investigation a simple procedure involving a single calibration specimen is suggested. The method utilises a theoretical solution available in the literature for an orthotropic circular disk under diametral compression, measured strains at specific locations on a circular disk specimen, and a least squares procedure that gives average rather than localised elastic constants.
Nondestructive Determination of Elastic Constants of Composite Materials