Load-bearing behavior of spliced glass beams under bending action

Abstract

The load-bearing behavior of spliced structural glass beams under bending action is investigated using FE simulations. Since geometric singularities occur in spliced structural glass beams, stress concentrations arise, which are the key issue regarding the bearing capacity due to the brittle failure mode of glass. FE simulations show that stress concentration factors of more than 2.6 may occur within the cross section of spliced joints. Furthermore, the simulations show that these stress concentrations highly depend on the stiffness of the interlayer material, which in turn strongly depends on the temperature and the load duration. In case of low interlayer stiffness, the stress concentrations are low as well, but the zone of influence of a joint is large. In case of a high interlayer stiffness, the zone of influence of a joint is small and therefore, the force in the spliced pane has to be transferred in a small area leading to high stress concentrations. Consequentially, different load scenarios with different assumptions regarding the stiffness of the interlayer material, have to be considered in order to get a safe design. In addition, an interaction of neighboring joints cannot be excluded and therefore, a simulation of the entire structure is strongly recommended. Optimized joint designs, such as thinner outer panes or the use of an intermediate pane, significantly reduce the stress concentrations in case of outer spliced joints. However, thinner outer panes lead to higher stress concentrations in inner spliced joints, which may result in a relocation of the critical stress concentration within the beam.