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A higher order displacement based formulation has been developed to investigate wave propagation in fiber-reinforced polymer composite laminated (FRPCL) plates. The formulation has been applied, as an illustration, to a plate made up of transversely isotropic laminae with the axes of symmetry lying in the plane of the lamina. Results for the plane as well as the antiplane strain cases are shown to be in excellent agreement with the exact solutions for isotropic and transversely isotropic single layered plates. Also, numerical results have been obtained for crossply (0 deg/90 deg/0 deg/90 deg) laminated composite plates, which agree very well with the previously published numerical results. The formulation can be employed to expeditiously investigate the dispersion characteristics of waves propagating in a plate with an arbitrary number of anisotropic laminae. [DOI: 10.1115/1.1352062]

A higher order displacement model based on a cubic axial strain, cubic transverse shear strain and quadratic transverse normal strain across the thickness of the beam, to model exactly the warping of the cross section is proposed which maintains zero stress at the top and bottom of the beam with out the aid of any shear correction factor. Numerical experiments carried out clearly bring out the efficacy of this model over the first order theory for laminated beams.

Some of the results of a study conducted by S.F. Muller de Almedia and J.S. Hansen on customizing manufacturing-introduced thermal residual stress to improve the buckling strength of laminated composite plates invite comment. De Almedia and Hansen should have realized that increases in normalized buckling load should not be as much in laminates supporting higher levels of thicknesses. The thickness effect on the buckling load during the presence of thermal residual stress was re-examined.

Some of the results of J.G. Papastravridis' study on time-integral variational principles for nonholonomic systems invite comment. The principles were efficiently supported by a geometrical interpretation of the discrepancies in the equations of motions was carried out by the variational approach. In addition, there are a number of ways in which geometrical concepts could be utilized to establish a unified view of control.

Presents an innovative idea of tailoring the manufacturing-introduced thermal residual stresses in order to enhance the buckling strength of laminated composite plates. Effects of the tailored thermal residual stresses; How buckling loads of reinforced plates are normalized; Thickness effect on the buckling load in the presence of thermal residual stresses.