Abstract
The second phase velocity curve of Mindlin plate approaches to the extensional wave velocity of thin plate, although the second velocity of Rayleigh-Lamb frequency equation of the theory of elasticity approaches to the transverse wave velocity of continuum. This defect can be solved by introducing new elasticity moduluses and cross-sectional constants, which are treated as functions of frequency. In the same way, the discrepancy between the first phase velocity curve of Mindlin plate and that of Rayleigh-Lamb frequency equation can be solved. The governing equations of new Mindlin plate theory can be used to analyse static and dynamic problems with many kinds of structural and load systems.
