A Novel Technique for Enhancing Stress Concentration Features in Glass

Abstract

The brittle material behaviour of glass means that stress concentration features, such as geometric discontinuities (e.g., drilled holes) and mechanical connectors can weaken the structural efficiency of some glass structures. The poor structural efficiency due to the stress concentrations usually makes annealed glass unsuitable in applications where stress concentrations present, such as glass–bolted joints. Laminated and tempered glass are preferred in building construction industry due to their high strength and safe failure behaviour, respectively. However, laminated and tempered glasses are expensive compared to annealed glass. Moreover, laminated and tempered glasses offer limited design and construction flexibility, since the tempering and the laminating processes cannot be done at construction sites. This paper shows that bonding a small strip of Glass Fibre Reinforced Polymer (GFRP) on the surfaces of glass around stress concentration features in annealed glass can enhance the load capacity and ensure post-peak load resistance. The results suggest that the bonded GFRP strips retarded the propagation of a few major cracks causing complete fracture of the glass, thereby ensured higher load capacity and post-peak load resistance compared to unreinforced annealed glass.  Since GFRP strips of small size are required in the proposed strengthening technique, the negative visual impact due to the translucent GFRPs are often negligible in most practical applications.