Dynamic Loading of the Rod at a Sudden Change of Elastic Foundation Structure

The mathematical model of dynamic process in the loaded constant evenly distributed load of structurally nonlinear system "beam - two-parameter foundation" is constructed, arising as a result of sudden change of physical and mechanical properties of the foundation, leading to zeroing of its shear rigidity. The solving of the static bending problem of a hinged beam fixed at the ends of the beam, supported by (если физически на него опирается, если нет, тогда operated) the Pasternak foundation, serves as an initial condition of the problem about the forced vibrations of the beam on the Winkler foundation, which occurred after a sudden formation of the defect. The solutions of static and dynamic problems are built using the method of initial parameters with the involvement of vectors of beam cross-sections states and matrixes of influence of initial parameters on the state of arbitrary cross-sections. To analyze forced vibrations, the decomposition of load and deflection of the initial static state into rows according to the forms of natural vibrations of the new state is applied.