Abstract: In this paper, von Karman’s set of nonlinear equation for large deflection of rectangular plates is at first converted into several sets of linear equations by taking central dimensionless deflection as perturbation parameter, and then, the sets of linear equations for plates with various ratio λ of length to width are solved with application of variational method. The analytical expressions for displacements and stresses as well as formulas for numerical calculation are worked out. The figures of maximum deflection-load end maximum stress with ratio H of length to width as a parameter are given in this paper. Through comparison, it is found that the results of this paper are quite in accord with experiments.

Key words: contaminant transport, unsaturated zone, numerical model, fluid-solid coupling interaction, asymptotical solution