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A general solution is obtained for dynamic bending of ideal rigid-plastic plates with a clamped or simply supported curved contour containing an absolutely rigid insert of an arbitrary shape. The plate is affected by a short-time high-intensity explosive dynamic load uniformly distributed over the surface. It is shown that there are several mechanisms of plate deformation. Equations for dynamic deformation are derived for each mechanism, and conditions of occurrence are analyzed. Examples of numerical solutions are given.Introduction. The issues of calculating structures under the action of intense short-time loads are very important in modern mechanics of deformable solids. To solve such problems, the model of a rigid-plastic body is widely used [1]. The model is based on the assumption that the body starts deforming when the stress reaches the ultimate value and plastic deformation becomes possible. Elastic deformations are neglected. For thin-sheet structural elements, this simplification allowed solving numerous issues of practical importance. The model of a rigid-plastic body was used in [2-9] to study the behavior of homogeneous plates with a complicated external contour under the action of arbitrary dynamic loads of high intensity.Structurally inhomogeneous plates are constitutive elements of many structures used in various areas of engineering. Flat shields are often equipped by reinforced closed technological hatches. Therefore, damage of plates with rigid inserts has to be examined. Up to now, this problem has been considered only for a circular plate with a rigid circle at the center under conditions of axisymmetric loading and attachment [10]. The method proposed in the present work allows, on the basis of the theory of an ideal rigid-plastic body, calculating plates with an arbitrary curved contour, which are attached in an arbitrary manner, have an absolutely rigid insert of an arbitrary shape, and are subjected to intense short-time dynamic loads. The method can be used for a wide class of approximate engineering calculations.1. We consider a plate made of an ideal rigid-plastic material with an arbitrary smooth convex contour l, which is clamped or simply supported (Fig. 1). In the central part, the plate has an absolutely rigid insert Z a with an arbitrary contour l 2 . The plate is subjected to a high-intensity dynamic load P (t) uniformly distributed over the surface. We consider explosive loads characterized by instantaneous reaching the maximum value P max = P (t 0 ) at the initial time t 0 with their subsequent rapid decrease. As the insert Z a remains rigid during its deformation, we assume that the ultimate flexural moment in the insert is greater than M 0 (the ultimate flexural moment in the remaining part of the plate) and ρ a /ρ 1, where ρ and ρ a are the surface densities of the plate and insert materials, respectively.The dynamics of the plate made of a rigid-plastic material can follow one of the three schemes of deformation, depending on the value of P max . Under loads lower than t...