An equivalent thickness for buckling verification of laminated glass panels under in-plane shear loads

Monolithic and laminated glass elements, as known, offer interesting opportunities in the realization of innovative architectures of modern buildings. Nevertheless, similar structural elements are typically brittle and slender, thus frequently subjected to buckling phenomena. In these hypotheses, the paper focuses on the load-carrying behavior of 2-layer and 3-layer simply supported laminated glass panels subjected to in-plane shear loads. Analytical formulations based on the concept of equivalent thickness are presented to describe with accuracy their typical behavior. As shown, predicted critical loads and load-transversal displacement relationships are in good agreement with numerical data obtained by using sophisticated 3D-FE models, as well as simplest but accurate geometrical simplified FE models. According to the suggestions that the Eurocodes give the verification of traditional structural elements, a suitable verification criterion appropriately calibrated to numerical and experimental predictions available in literature is suggested to guarantee the requisites of resistance, serviceability and durability typically imposed in the design of conventional structural systems made of steel, concrete or timber. As a result, the proposed approach could be used in daily practice to perform a suitable and rational buckling verification of such brittle load-bearing elements.