The purpose of this work is the study of the mechanical behavior of two different sandwich composite in static and fatigue analysis of three-point bending, using different amount of glass fiber laminated as skins, remaining with same total thickness. The specimens are composed of glass fiber cloth and epoxy resin. The static tests provided the mechanical properties used in numerical simulations as well as fatigue tests analysis. Applying controlled displacement, it was analyzed load reactions, lifetime and failure modes during fatigue tests. Identifying the failures modes in microscopic analyses it was perceived adhesive fracture in fiber/matrix as first damage and core rupture as ultimate damage.

No abstract

The purpose of this paper is the study of mechanical behavior in three-point bending of polymer epoxy using different amount of glass fibers laminated faces as reinforcement. Therefore, it was used experimental method, numerical simulation using linear and non-linear method and analytical method of composite beams analysing force, displacement and normal stress. The specimens were prepared using hand lay-up process and vacuum bag compaction. It was realized tensile and flexural tests in the specimens obtaining mechanical properties used in numerical simulation and analytical method. The numerical simulation was performed using linear and non-linear method with 3D solid elements. The materials were considered isotropic. The results showed similar values between methods with emphasis for the non-linear simulation that most approached the experimental results. 1.

Sandwich structures have become effective structural elements for engineering applications due to their good design flexibility. Understanding the material behavior under static and dynamic loads, as well as the failure mechanisms of these sandwich structures, is of great importance. This work evaluates the fatigue and static bending behavior of epoxy resin specimens and sandwich composites composed of an epoxy resin core with glass fiber laminated faces. The fatigue life, failure modes, and stiffness degradation of these specimens are determined experimentally. The specimens were cycled under constant amplitude and monitored by a data acquisition system that allowed continuous data collection. Three stages of failure were identified using microscope analyses and stiffness degradation curves. In the case of an imposed displacement of 2 mm, the sandwich structures were shown to have a significantly lower fatigue life than the epoxy resin specimens.