This investigation is concerned with the determination of elastic and inelastic buckling of multi-stepped rectangular plates based on the classical plate theory. Due to complexity of the closed form solutions for buckling analysis of stepped plates with different boundary conditions, numerical methods were more recommended. Because of restrictions for two finite strip methods (Classical and Complex method) the spline finite strip method is used to solve the buckling problem. In spline finite strip method, the longitudinal spline expressions combined with conventional transverse shape functions are used as the displacement functions. In this study by using spline as longitudinal functions the abrupt longitudinal changes in thickness of plates were modeled and evaluated. Local buckling coefficients are presented for plates having one- and two step thickness variations which are useful to economize on the plate materials or to lighten the plates.
