Analysis of shear flexible beams, using the meshless local Petrov-Galerkin method, based on a locking-free formulation

The problems of shear flexible beams are analyzed by the MLPG method based on a locking-free weak formulation. In order for the weak formulation to be locking-free, the numerical characteristics of the variational functional for a shear flexible beam, in the thin beam limit, are discussed. Based on these discussions a locking-free local symmetric weak form is derived by changing the set of two dependent variables in governing equations from that of transverse displacement and total rotation to the set of transverse displacement and transverse shear strain. For the interpolation of the chosen set of dependent variables (i.e. transverse displacement and transverse shear strain) in the locking-free local symmetric weak form, the recently proposed generalized moving least squares (GMLS) interpolation scheme is utilized, in order to introduce the derivative of the transverse displacement. through numerical examples, convergence tests are performed. To identify the locking-free nature of the proposed method, problems of shear flexible beams in the thick beam limit and in the thin beam limit are analyzed, and the numerical results are compared with analytical solutions. The potential of using the truly meshless local Petrov-Galerkin (MLPG) method is established as a new paradigm in totally locking-free computational analyses of shear flexible plates and shells.