Safety Design of Laminated Glass Regarding PVB Interlayer Stiffness for Large Glass Facades and Shop Windows

When looking at current architecture, we can notice large glass facades and shop windows. These elements are usually made of laminated glass panes with polymeric interlayer between and the task of shear forces transfer is the subject of a current survey especially in case of accidental load cases. It essentially depends on polymer material stiffness, which is temperature, load duration and loading rate dependent. A lot of different polymeric interlayers with different properties are available on a market but their experimentally determined material properties with respect to the load duration and temperature are not mostly specified. Structural engineers tend to design laminated glass structural elements on the safe side and do not take the interlayer stiffness into account. This leads to uneconomical and robust glass bearing members. In case of accidental load verification, shear stiffness of used interlayers plays a significant role. This paper is focused on two types of PVB (polyvinyl-buthyral interlayers) experimental investigation under various temperature and loading rate conditions.