Second-Order Theory in Orthotropic Plates

The basic equations for the stress analysis of an orthotropic plate are given. These equations take into account bending and membrane stresses. Various methods of solving the basic equations are discussed briefly. One method is discussed more fully, namely, that of using finite-difference equations with simultaneous equations and programmed for a digital computer. This computer program was applied to a selected number of both isotropic and orthotropic plates. Results of tests on small-scale isotropic and orthotropic plates are given. The test results are compared with results obtained from the computer program. The computer program is applied to an orthotropic plate bridge deck to determine the bending and membrane stresses caused by truck loads. Analytic and experimental results are summarized and pertinent conclusions are drawn concerning the appearance and magnitude of membrane stresses in plates.