Ultimate strength of cold-formed steel z-purlins

INTRODUCTION Cold-formed steel structures are being widely used in various forms of construction such as industrial plants, gymnasiums, hangars and metal buildings. One important feature of metal building construction is the use of light gage roof panels connected to purlins, particularly of the Z-section. This section is, besides the channel-section, the simplest two-flange section which can be produced by cold-forming. The purlins have span lengths of 20 to 25 feet, generally made continuous over the building rigid frames by nesting. Construction details vary from manufacturer to manufacturer. The purlins available would typically have prepunched holes for connection of various types of bracings, overlapping connections, etc