Research and Modeling of Stress-Strain State and Fracture Strength of Triplexes at Temperatures 293–213 K

This article presents the data of complex research of multilayer structures (triplexes). Triplexes are widely used for the glazing of vehicles (cars, railway vehicles, aircrafts and ships), as well as windows and facades of buildings. The transparent dielectric structural materials (inorganic silicate glass, organic silicate glass, epoxy resin) are constituent parts (elements) of such triplexes. To determine the stress-strain state (SSS) of such objects in the presence of crack-like defects in their constituent elements, the modified photoelastic method for the investigation of optically low-sensitive materials has been developed. The regularities of kinetics of cracks growth in inorganic silicate glass as a material of homogeneous and heterogeneous triplexes are studied. The data about the fracture of organic glass as a material that is part of heterogeneous triplexes is analyzed. In order to evaluate the complex influence of the framing (structural and technological) on the values of stress intensity factors (SIF) for crack-like defects in the adhesive layer, the series of experiments have been conducted to determine the SIF for surface and transverse cracks in the epoxy resin. Modeling of the framing influence on the nature of the stress intensity factors behavior in multilayer structures is performed using finite elements method (FEM). Having conducted studies on the determination of the SSS and the SIF, the boundary condition of the four types of triplexes (with and without framing) is estimated at temperatures 293-213 K, and the optimal is suggested.