Investigating the impact of thermal stresses on blistering effects in sandwich panels

Lightweight steel constructions made of sandwich panels are an economical solution for wall and roof claddings, especially in industrial construction. The panels consist of two thin sheets of steel and a core with thermal insulating properties. In the mounted state and at high temperatures on the outer face of the panel, damage to the components may occur due to blister formation. In a current research project, the influence of defects in sandwich panels with a PIR‐foam core is examined. This article presents the results of experimental tests regarding the influence of various parameters, such as face temperature, production defects and design of the longitudinal joint on blistering in sandwich wall panels with a PIR‐core. The aim is to identify the necessary conditions for the occurrence of blisters. Using an optical strain measuring method (Digital Image Correlation), the temperature‐induced deformations and strains in the covering nose of sandwich wall panels with hidden fastening are measured and will be analyzed with regard to blistering. First results reveal a significant dependence on the geometry and design of the covering nose.