A new constitutive model for bimodular laminated structures: Application to free vibrations of conical/cylindrical panels

In this paper, a constitutive model is proposed for analysis of bimodular composite laminated structures. In case of already existing Bert’s model, the material properties are assigned according to the nature (tensile/compressive) of only fiber direction strain. In the proposed model, the material properties are assigned according to the nature of fiber direction and transverse to fiber direction normal strains. The proposed model is used for free vibration analysis of cylindrical and conical panels. First order shear deformation theory based finite element is employed to obtain the free vibration frequencies and through the thickness modal stress distributions. The free vibration frequencies predicted from the two models for the parameters considered are found to be very close to each other but transverse to the fiber direction normal stress distribution using both the models is significantly different.