Meshfree flat-shell formulation for evaluating linear buckling loads and mode shapes of structural plates

We concentrate our attention on developing a meshfree flat-shell formulation for evaluating linear buckling loads and mode shapes (modes) of structural plates employing an eigen value analysis. A Galerkin-based shear deformable flat-shell formulation for that purpose is proposed. The in-plane and out-of-plane deformations are interpolated using the reproducing kernel particle method (RKPM), while the two membrane deformations, and the three deflection and rotational components are, respectively, approximated through a plane stress condition and Mindlin–Reissner plate theory. The meshfree discretization by which, as a consequence, constructs five degrees of freedom per node. A generalized eigenvalue problem for the solution of buckling loads and modes of the structural plates is then described. The stiffness matrices of the linear buckling analysis are numerically integrated based on the stabilized conforming nodal integration (SCNI) and sub-domain stabilized conforming integration (SSCI). The RKPM and SCNI/SSCI based on Galerkin meshfree formulation, i.e., stabilized meshfree Galerkin method, can overcome the shear locking problem by imposing the Kirchhoff mode reproducing condition. In addition, a singular kernel (SK) function is included in the meshfree interpolation functions to accurately impose the essential boundary conditions. The merits of the developed formulation are demonstrated through numerical buckling experiments of several examples of plates, by which the accuracy and performance of the proposed method are investigated and discussed in detail. It indicates from our numerical results of buckling loads and modes that the proposed meshfree formulation is accurate and useful in the simulation of buckling problems of structural stiffened plates.