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A significant number of investigations has been performed to improve the unsafe (brittle) failure behaviour of glass beams. Similar to reinforced concrete, reinforced glass beams have been developed in which stainless steel is embedded in the glass laminate to obtain safe failure behaviour. The concept has been proven to be feasible when assuming statically determinate systems.However, the additional system safety of statically indeterminate systems has not been investigated yet. This paper presents numerical research outcomes on reinforced glass beams with statically determinate as well as statically indeterminate support conditions. In a first step, a model of a twosided reinforced beam subjected to three-point bending was created for validation purposes. The thickness and height of the constituents making up the model were based on experimental measurements of test specimens. Subsequently, the same numerical model was made using nominal dimensions for the glass and reinforcement. In this way, the effect of dimensional tolerances on the load-carrying behaviour was investigated. Furthermore, a single-sided reinforced glass beam was modelled under the same loading conditions to assess the effect of adding compressive reinforcement. In a second step, statically indeterminate two-sided reinforced beam models were constructed based on the statically determinate model. From these preliminary models, the load-carrying behaviour and effect of reinforcement percentage were evaluated. Finally, also the stress redistribution capacity of both beam models was assessed. It is concluded that dimensional tolerances have a significant effect on the load-carrying behaviour and should therefore be accounted for in the design of reinforced glass beams. The additional compressive reinforcement provides slightly higher bending stiffness, initial failure load and yield load to the glass beams, although it does not contribute in the yield phase. However, a different ultimate collapse mechanism is expected as the compressive reinforcement can take the stress when the glass compressive zone has failed. The statically indeterminate simulations proved the feasibility of applying reinforced glass beams in statically indeterminate systems as a safe failure behaviour was observed with significant stress redistribution capacity. Changing the reinforcement percentage has a significant effect on the load-carrying behaviour of these systems. However, the overall behaviour remains safe

This paper presents a study on posttensioned glass beams in a statically indeterminate system. In order to increase the safety of structural glass beams, ductile reinforcement can be added to glass beam sections providing secondary load carrying mechanism in case of glass breakage. In the here investigated post-tensioned system, the reinforcement tendons are additionally pre-tensioned, introducing compressive pre-stress in the beam in order to increase the apparent tensile strength of glass. The system is tested in five-point bending at 23 and 60 • C in order to investigate the basic structural performance and the influence of temperature increase on the initial cracking load and the behaviour of the cracked beam. The benefit of the here investigated statically indeterminate system is a more economical design, i.e. lowering of the bending moment in the span of an equivalent simply supported system by continuing the beam over the central support. The efficiency of the applied system is compared to a reinforced beam system produced in the same batch with similar overall dimensions. The results show an increase of initial cracking load of the post-tensioned beams due to the applied pre-stress and a ductile post-cracking response, reaching high ultimate loads prior to failure. At 60 • C both reinforced and post-tensioned beams show lower initial cracking loads and limited post-cracking ductility but still significant load reserve with ultimate loads well above the initial cracking loads, providing safe failure behaviour.