PREDICTION OF FRACTURE OF EGGSHELL USING OPERATIONAL MODAL ANALYSIS

Presence of crack in eggshell are suspect able due to higher speed in commercial egg grading
machines, so non-destructive quality assessment of bioproducts using vibration analysis, the
resonant frequency and the damping of the vibration are the main parameters for the non￾destructive quality assessment. The focus of this research is to investigate the capability af the
operational modal analysis as a nondest~ctive tool, to characterize and to quantify the fracture
behavior of eggshell. This is achieved by studying the response of modal testing to the variation
in strength as the main factor affecting fracture. This help in correlating modal parameters to
fracture behavior. Two different methods are achievedl- traditional modal analysis using transfer
fnnction between actuator and sensor and 2- operational modal analysis using transmittance
function between pairs of sensors, input excitation was provided through a piezoelectric force
transducer bonded to the center of the cup used for egg installation in order to extract the
corresponding modal parameters and damping ratio. The test for strength was performed on eggs
to correlated modal parameter to behavior of f~acture. This enables the evaluation of the ability of
modal testing to predict fracture using an empirical formula. The damage index based on change
in transmittance function is very sensitive to change in crack length. Structural information
obtained about a biomaterial at diierent length scales is important in relating the structure to its
funclional properties. This knowledge and the principles behind the formation of biomaterials
could be used in the attempt of bioengineering new systems.