Statistical method to evaluate the process capability index of laminated glass regarding impact resistance

Laminated glass is used worldwide in buildings for its ability to break safely and to prevent the penetration of an impacting object. These abilities are described by standards, such as EN356 for resistance against manual attack or so-called ”anti-vandal” glazing products.

One of the test is the hard body drop test, where three steel balls are dropped successively on a glass piece. The level of classification depends on the drop height.

Today, there is an increasing demand for safety and anti-vandal functions associated with a preference for weight reduction and high transparency, meaning relatively thin glass with high performance. It becomes necessary to have a reliable and quantitative way to evaluate the capability of a product regarding such testing. In this work, we discuss the statistical significance of the hard body drop test and propose a method inspired by the automotive sector.

Based on maximum likelihood theory, this method gives a statistically significant quantification of the impact resistance and allow to build capability index for a given product. Using this new method, we tested more than 2000 m² of laminated glass of various compositions.

About the Speaker

Keyvan Piroird works for Saint-Gobain in the research center located near Paris (Saint-Gobain Reserach Paris). He is in charge of the R&D platform for laminated glass in building applications for Saint-Gobain Glass.