Development of An Improved Technique For Identification of the Damping Properties of Orthogonally Reinforced Composites in Shear

A technique for identifying the amplitude dependences of the logarithmic decrement of vibrations of orthogonally reinforced composites in shear by using a refined model of deformation that takes into account the effect of the transverse strain in tension–compression of a layer package with a ± 45° lay-up relative to the longitudinal axis of the test specimen. The unknown dependences are represented by power functions with two unknown parameters, which are determined by minimizing the quadratic residual between the calculated and experimental internal damping parameters of test specimens. A comparison between the results of the shear damping properties of a CFRP, reinforced with a Porcher 3692 fabric, obtained with and without account of the transverse deformation of test specimens with the lay-up mentioned, is carried out.