Local failures in trapezoidal steel claddings

摘要

When crest-fixed thin steel roof claddings are subjected to wind uplift, local pullthrough/dimpling failures occur prematurely at their screwed connections because of the large stress concentrations in sheeting under the screw heads combined with lack of steel ductility. During high wind events such as storms and cyclones, these localized failures then lead to severe damage to the buildings and their contents. At present the design of profiled steel claddings is based on testing of two-span cladding systems to eliminate such failures. However, this is a time consuming and expensive exercise. Therefore an investigation was conducted to develop simple tests and design formulae for crest-fixed steel claddings based on detailed experimental and finite element analyses of steel claddings. This paper presents the details of this investigation. It includes a description of the types of local failures and appropriate design formulae.