MODELING OF DYNAMIC STRESS STATE FOAM MEDIA UNDER THE ACTION OF CONCENTRATED LOAD

Abstract

The influence of impulse concentrated load on the distribution of normalized dynamic hoop stresses in the foam medium is investigated in this paper. For the solving of the non-stationary problem in the case of plane deformation for the structurally inhomogeneous materials, the model of Cosserat continuum is applied. This model enables accounting for the influence of shear-rotation deformation of micro-particles of the medium. In the framework of Cosserat elasticity with the applying of the Fourier transforms for time variable and developing of the boundary integral equation method the solving of the non-stationary problem reduces to the system of singular integral equations, where the components that determining the influence of shear-rotation deformations are selected. The numerical calculations were performed for the polyurethane closed-cell foam with tunnel cavity of circular cross-section under the action of localized impulse load. The developed approach can be used to predict the mechanical behaviour of foam materials under the action of time-variable load based on the analysis of the distribution of dynamic stresses.