Beam on Elastic Foundation Finite Element

A stiffness matrix for a beam on elastic foundation finite element and element load vectors due to concentrated forces, concentrated moments, and linearly distributed forces are developed for plane frame analysis. This element stiffness matrix can be readily adopted for the conventional displacement method. For the force method, an element flexibility matrix and element displacement vectors due to the aforementioned loads are also presented. Whereas most other analyses of a beam on elastic foundation finite element approximate the foundation by discrete springs or by cubic hermitian polynomials, the present stiffness and flexibility matrices are derived from the exact solution of the differential equation. Thus, results of this finite element analysis are exact for Navier and Winkler assumptions. Numerical examples are given to demonstrate the efficiency and simplicity of the element.