This paper presents the bending analysis of annular plates by the indirect Trefftz boundary approach. The formulation for thin and thick plates is based on the Kirchhoff plate theory and the Reissner plate theory. The governing equations are therefore a fourth-order boundary value problem and a sixth-order boundary value problem, respectively. The Trefftz method employs the complete set of solu...

This paper presents a numerical solution for vibration analysis of a cantilever trapezoidal thick plate. The material of the plate is considered to be graded through the thickness from a metal surface to a ceramic one according to a power law function. Kinetic and strain energies are derived based on the Reissner-Mindlin theory for thick plates and using Hamilton's principle, the governing equa...

In this work-in-progress we report on a new approach to obtaining stable locking-free discretizations of the Reissner–Mindlin plate model. For a plate of thickness t with midplane section Ω ⊂ R the clamped Reissner–Mindlin plate model determines ω , the transverse displacement of the midplane, and φ , the rotation of fibers normal to the midplane, as the unique minimizer over H̊1(Ω)× H̊(Ω) of the...

This paper establishes a very general theory for a posteriori error analysis of finite element methods of the Reissner-Mindlin plate problem in the literature. The theory assures reliability of explicit residual error estimates. The conclusion of this theory is sparsity in the mathematical research of uniform a posteriori error control. Indeed, the a posteriori error estimate for various finite...

We investigate the structure of the solution of the Reissner–Mindlin plate equations in its dependence on the plate thickness in the cases of soft and hard clamped, soft and hard simply supported, and traction free boundary conditions. For the transverse displacement, rotation, and shear stress, we develop asymptotic expansions in powers of the plate thickness. These expansions are uniform up t...

A Balancing Domain Decomposition Method by Constraints (BDDC) is constructed and analyzed for the Reissner-Mindlin plate bending problem discretized with MITC finite elements. This BDDC algorithm is based on selecting the plate rotations and deflection degrees of freedom at the subdomain vertices as primal continuity constraints. After the implicit elimination of the interior degrees of freedom...

This paper has introduced two kinds of combined hybrid variational formulations for plate bending finite elements based upon the Reissner–Mindlin theory, according to whether assumed constant moment stress is introduced when assumed constant shear stress has been introduced. Due to two options for incompatible displacement modes, four new types of combined hybrid elements are proposed. A set of...

The Reissner-Mindlin plate models thin plates. The condition numbers of finite element approximations of these plate models increase very rapidly as the thickness of the plate goes to 0. A Balancing Domain Decomposition by Constraints (BDDC) Deluxe method is developed for these plate problems discretized by Falk-Tu finite elements. In this new algorithm, subdomain Schur complements restricted t...