Repair of soda–lime–silica glass

Abstract

Glass strength is very sensitive to damage accumulation during its service life. Repair methods for glass have been proposed over the last decades to volumetrically fill or remove existing flaws from the surface of glass. However, the lack of information on the strength recovery attributable to glass repair methods restrict their use to low consequence class applications in buildings thereby making replacement of damaged installed glass the only safe and practical solution when dealing with damaged glass. Repair methods involving volumetric filling of visible flaws with resins, removal of visible flaws with polishing and chemical repair with acid treatment of visible flaws are undertaken in this study to investigate the strength recovery in 60 artificially aged annealed glass specimens. It is found that the polishing provides the most promising strength recovery results showing a 132 and a 40% increase in design and mean strength whilst the acid treatment provides the worst performance. Polishing repairs are further investigated in this study to determine their efficacy in strength recovery after environmental ageing (exposure to UV, humidity and freeze-thaw cycles).