Investigation of hybrid steel-glass beams with adhesive silicone shear connection

Glass is used in current construction applications mostly as a façade element, its structural role being only rarely exploited, despite its significant resistance to in-plane compression. A steel-glass composite beam was built to investigate a hybrid steel-glass assembly and its loadbearing behaviour. To fulfil this objective, the existing types of steel-glass connection were evaluated, which allowed the possibilities offered by adhesive jointing to be highlighted. The selection of the adhesive, detailed in the present article, constituted a crucial aspect. An excessively soft connection does not transfer the shear loads between the glass and steel adherends, whereas an excessively stiff connection leads to failure of the glass. A two-component structural silicone was chosen and its properties were assessed with the help of an intensive test programme. As a result of this programme, a new quasi-incompressible hyperelastic material law was developed in order to represent the silicone elastomer behaviour. Numerical simulations were conducted in parallel to large-scale four-point bending tests on the adhesively bonded steel-glass composite beams. The aims were, on the one hand, to assess the bending stiffness of the steel-glass composite beam and, on the other, to validate the numerical simulations to conduct parametric studies.