EN
Implementation conditions postbuckling stages of straining of plastic materials taking into account properties of loading system are investigated, management with which is carried out with use of planar specimens of special design. The analysis of received conditions allows to predict the material destruction moment in any point of softening branch at partial implementation postbuckling straining stages in working zone of specimen. Results of mathematical modelling are important for substantiation of specified calculation techniques of bearing and survivability estimation of designs taking into account initiation of destruction zones, in which the postbuckling stages implementation extent by destruction time depends on concrete loading conditions, properties of material and system geometry.