Thin glass below 2 mm in thickness is becoming increasingly interesting in façades with the growing importance of lightweight construction. Chemically strengthened thin glass offers high strength and flexibility; as a result, its large deflection capacities can be exploited by active cold bending, leading to new applications such as adaptive façades. To meet safety requirements, thin glass should be laminated. However, compared to conventional laminated safety glass, laminated thin glass (LTG) exhibits a much lower glass-to-interlayer ratio. In this study, the behaviour of LTG under torsional deformation was investigated through a long-term experiment. A test rig was developed to evaluate the long-term behaviour experimentally. Specimens composed of two 0.7 mm chemically strengthened thin glass panes with ethylene vinyl acetate (EVA) and multilayer interlayer with EVA and modified polyester (MPE) were subjected to a fixed torsional angle of 30° for 3,100 h (approx. 130 days). The torsional moment was continuously monitored to determine the time-dependent shear stiffness. Afterwards, the fixation was removed to observe the extent of shape recovery. The results showed that even after a recovery time of 800 h (> 30 days), the LTG showed permanent deformation. This highlights the necessity of accounting for the mechanical properties of the interlayer in structural design. This is particularly important for applications involving repeated deformation, such as adaptive façades.
In glass melting, combining glasses with differing coefficients of thermal expansion (CTE) and viscosity can generate stresses and cracking. In recycling contexts, however, full separation of glass types is sometimes challenging or economically unviable. This study examines how the processing parameters cullet size, peak temperature and dwell time influence the tolerance of mixed‑glass systems to CTE and viscosity mismatches in a casting setup, with the aim of clarifying stress‑relief mechanisms and miscibility effects. Pairs of glasses were cast in investment moulds, making tiles of 50 × 50 mm size and circa 5 mm thickness, using combinations with varying CTE mismatches at a 1:1 weight ratio. Clear glasses of known composition were used, including soda-lime, borosilicate and alumino-borosilicate types. Different cullet sizes were fired at varying peak temperatures and dwell times. Specimens were then evaluated for bonding, homogeneity, residual stress, and cracking. A heuristic mismatch index was additionally constructed to describe the combined influence of viscosity and CTE on compatibility. Results show that compatibility cannot be predicted from CTE mismatch alone. Cullet geometry, viscosity behaviour, and thermal history can strongly affect bonding and fracture likelihood. Powdered cullet and high peak temperatures (≥1120 °C) consistently increased tolerance to CTE differences by promoting enhanced flow and partial interdiffusion. The mismatch index performed well for conditions dominated by fusion but was less applicable when substantial interdiffusion occurred. Overall, the findings demonstrate that compatibility in mixed‑glass casting is process‑dependent rather than governed by fixed material thresholds, offering a basis for improved assessment and utilisation of heterogeneous waste-glass streams.
The increasing use of all-glass structures has been enabled by advances in glass manufacturing, allowing glass beams to be employed as primary load-bearing elements. Owing to the intrinsic brittleness of glass and the absence of visible pre-failure indicators, ensuring adequate post-fracture behaviour is essential to maintain structural integrity and prevent progressive collapse. This paper presents an experimental investigation into the post-fracture behaviour of four full-scale glass beams from realised projects constructed between 2012 and 2026 in Ireland, France and Italy. The study evaluates the residual load-bearing capacity of different laminated glass configurations, focusing on the influence of laminate typology, assembly techniques and redundancy systems. Particular attention is paid to the role of alternative load paths in preserving structural stability after localised failure. The results reveal substantial differences in post-fracture performance between the tested configurations, highlighting the critical importance of material selection and structural detailing. The findings contribute to the definition of robustness and damage-tolerance criteria for load-bearing glass elements and support the experimental validation of numerical design approaches.
Silicone bonded glazing (structural glazing) is a pivotal technology in curtain wall systems, offering a seamless and aesthetically pleasing facade for modern architectural designs. This technique uses wet applied silicone sealants to bond glass to a building's structural frame, eliminating mechanical fasteners and providing a sleek, uninterrupted glass surface. Some of the proven advantages include long term thermal insulation and excellent resistance to various loads. The durability of the silicone means less maintenance and replacement over time of a bonded façade. A significant innovation in silicone bonded glazing is the development of a new bonding silicone solution which improves productivity, sustainability, cost, design options and aesthetics. The silicone is pre-applied as a strip on a metal frame or insert. This post-cure strip develops adhesion to glass through a simple primer application even after months of storage. As the strip is already cured, bonded glazing units can be quickly assembled and shipped. The pre-dispensed controlled joint dimension minimizes the risk of errors and reduces material waste. The silicone strip allows reducing the overall silicone, spacer tape and aluminum content for structural glazing elements. This contributes to a more cost effective and lower environmental footprint bonding system. This paper reviews the key properties and possibilities offered by this new silicone bonded glazing technology.
Vast quantities of post-consumer glass from commercial buildings are still lost to landfill due to contamination, logistics, and cost barriers. This paper shares key lessons from implementing a new, scalable pathway to recover end-of-life architectural glass and return it to new building glass. Through strategic partnerships with clients, upskilling the deconstruction supply chain, and stewardship of recovered material, Saint-Gobain has developed a cost- and time-effective closed-loop solution. This initiative is the Saint-Gobain Glass Recycling Process, summarised in a six-step circular flow: (1) Diagnosis – Classification of interior/façade types and glass types prior to dismantling; (2) Dismantling – Controlled breaking of glass to prevent contamination; (3) Sorting – Organisation of acceptable cullet types for recycling; (4) Collection – Arrangement of glass flows to ensure compatibility with flat glass production; (5) Melting – Acceptance and integration of cullet into new glass batches; (6) Projects – Reuse of recycled glass in new facades for construction and renovation. This closed-loop system is applicable across various building lifecycle stages—from demolition to new construction—and exemplifies how industrial innovation can drive climate resilience and material circularity in the built environment.
