RigidPlastic Analysis of Floating Plates

The exact formulation and solution for the static flexural response of a rigid perfectlyplastic freely floating plate subjected to lateral axisymmetric loading is presented. The square yield condition is adopted with the associated flow rule. The plate response is divided into three phases. Initially, the plate moves downwards into the foundation as a rigid body phase I. Subsequently, the plate deforms in a conical mode in addition to the rigid body motion phase II. At a certain value of the load a hingecircle forms which may move as the pressure increases further phase III. The nature of the solution during the third phase depends upon the parameter α=a/Rratio of radius of loaded area to the plate radius. When α=αs≃0.43505the hingecircle remains stationary under increasing load. For α<αsthe hingecircle shrinks, whereas for α>αsthe hingecircle expands with increasing pressure. The application of the present results to the problem of laterally loaded floating ice plates is examined.