Stress distribution at the load introduction point of glass plates subjected to compression

Abstract

Often a crucial place in glass design is the point of load introduction where a high in-plane compression load is introduced in the glass. In this case, the common hypothesis that glass fails when the tensile stresses reach their tensile strength, seems not to be true. More specifically, at the load introduction point, a complex two-dimensional stress state takes place and the glass failed at tensile stress levels far below its tensile strength. To study these phenomena, laboratory investigations and numerical simulations of glass plates with a low slenderness (to avoid stability problems), subjected to in-plane compressive loads introduced through boreholes by point fixing devices, were conducted. At the load introduction point (contact point), maximal principal compressive stresses occurred. Due to Poisson's effect, perpendicularly to this compressive stresses the maximal principal tensile stresses took place. At a certain distance from the load introduction point, the compressive stresses became constant over the glass width while the tensile stresses disappeared. Parametric investigation studied the influence of boreholes distance on the stress distribution at the contact point. For distances larger than the glass panel width, the stress distribution remained unchanged, while for distances smaller than the panel width, a significant influence was recognised.