the homogeneous and stratified beams, model of an ideal rigid and plastic body, yield points, the limiting moment of deflection, structural weight, residual deflection, rational project.

For an assessment of effectiveness of flat barriers at influence of loadings usually dependence of parameters of their residual damageability on amplitude is investigated or shockwave impulse. In relation to the homogeneous isotropic plates such decisions are under construction on the basis of model of ideal rigid and plastic bodies, show sufficient effectiveness of results and quite satisfactory coincidence to experiments. Solution of many tasks and review the received results for the homogeneous beams and plates it is possible to find in [1], [2]. In many fields of the modern technique the existing strict conditions to cannot be provided to maintainability of a design at use of the homogeneous materials there are also serious hopes on use of composite designs. It is clear, that on this way can be efficient designs of protective barriers are created. First of all here it is necessary to investigate possibilities of stratified barriers. Now there is a large amount of the technologies allowing to create a stratified package from almost any materials with significantly various properties. To them it is possible to refer, in particular, technologies of pasting of diffusion welding under pressure and welding by explosion, plasma or cold gasdynamic dusting, magnetic and ultrasonic naplavka, vacuum and chemical deposition, electronic and arc metallization and others. For the designs intended to to perception of explosive loadings, the most acceptable, apparently, follows to consider a weld procedure explosion as the cheapest and providing strong connection practically any metals on larger squares [3]–[5]. At it there is a problem of the analysis of behavior and an assessment of effectiveness of such designs from the point of view of their damageability at influence of loadings explosive type.

Nemirovskii Yuri Vladimirovich, Dr. Sci. Phys. & Math., Professor, Leading Research Associate at Khristianovich Institute of theoretical and applied mechanics of the Siberian Branch of the RAS, Novosibirsk, Russia.