Free Longitudinal Vibrations of Rubber and Tissue Strips

Frequencies of free longitudinal vibrations of several different specimens of rubber and aortic strips were measured as a function of applied load and relative length L/L0, where L0 is the initial length. Curves of ω2L0/g versus L/L0 have distinct minima that become sharper and move upward and toward the ω2L0/g axis as the specimens become stiffer. The experimental curves are described rather well by theoretical equations derived from current relations for the extension of an ideal elastomer; they may be used for determining values of the elastomeric parameter β. The method is simple and rapid and is applicable to biological tissues as well as to other rubberlike substances.