Dynamika sztywnej płyty spoczywającej na sprężysto-plastycznym podłożu ze zmienną granicą plastyczności. Część I. Sztywne odciążenie

In the paper the parameters of motion of a rigid plate resting on elastic-plastic medium with varying plastic yield limit was investigated. The investigations were carried out for rigid unloading. The plate was loaded with uniformly distributed pressure which at first was suddenly applied and next was allowed to decrease monotonically up to the zero value. Under these conditions and for the respectively chosen load the plate generates in the medium the plastic loading waves, which are followed by unloading process. For the fronts of plastic loading and unloading waves the usual nonlinear differential equations with shifted arguments containing the sought functions (wave fronts) were obtained. The equations were solved with the help of a digital computer. The closed formulae for initial velocities of propagation of plastic loading and unloading wave were derived. The motion parameters of the plate and its reaction transmitted to the medium depending on the nonhomogeneity of the plastic yield limit were numerically investigated.