Inverse determination of effective mechanical properties of adhesive bondlines

A new approach for determining effective mechanical bondline properties using a combined experimental-numerical modal analysis technique is proposed. After characterizing clear spruce wood boards, an adhesive layer is applied to the boards surfaces. The shift of the eigenfrequencies resulting from the adhesive layer together with information on the bondline geometry can then be used to inversely determine the mechanical properties of the adhesive layer using Finite Element Models. The calculated values for clear wood as well as for the adhesive layer lie within reasonable ranges, thus demonstrating the methods potential.