Deformations in Fragments of Tempered Glass – Experimental and Numerical Investigation

Tempered (or toughened) glass is used for a number of applications ranging from shower doors over car windows and building envelope to actual load-carrying structural elements such as beams, plates and shells.

One of the challenges with tempered glass is to assemble it. Using traditional bolts require all holes to be drilled prior to the tempering process which again requires a high level of planning and unavoidably leads large tolerances due to high temperatures. Furthermore, some plate geometry might fail during tempering finally; it also requires a significant effort to estimate the apparent strength for a complicated geometry.

Adhesives are an obvious alternative, where the pre-tempered process can be avoided. Again, adhesives might show time-dependent properties and can react with the ambient conditions (UV-light, moisture, temperature etc.)

This paper describes a pinned connection utilizing non-through drilled holes in tempered glass. Since the holes are not drilled all the way through the glass, they can be drilled after the tempering process. Small holes are used (diameter less than 5mm) and it has been shown that the residual stresses are redistributing in a favorable way. This paper describes the strength of a connection based on this principle.