Development of a Methodology for the Calculation of Youngʹs Modulus of Eggshell using Vibration Measurements

Existing methods for the determination of the elastic modulus of eggshell depend on static measurements. In this work, dynamic measurements are performed in order to determine the elastic modulus of a shell segment. A test procedure was developed, which excites a shell segment and measures its resonant frequency. This resonant frequency together with the dimensions of the shell segment form the base for the calculation of the dynamic elastic modulus. A formula for the elastic modulus was derived using modal analysis of a shell segment. The elastic modulus of image-layer eggs was measured to validate the technique. For each egg, three shell segments were sawn along the equator. The average value for the modulus of the eggs was image. The variance between the modulus of the eggs was image. These values are in line with the values of the static modulus mentioned by other investigators. Furthermore, the variance between measurements on the same shell segment was image indicating that the test procedure provides repeatable measurements.