Web crippling strength of a steel sandwich panel with V-shaped webs

Steel sandwich panels with V-shaped web flutes (V-core panels) serve the structural functions of a proposed energy-efficient roof system for residential construction. Due to its intended use as a flexural member spanning between a ridge beam and a structural wall, and required slender webs for weight considerations, web crippling under end one-flange loading is a critical strength limit state for the V-core panels. Although the 2001 North American Specification for the Design of Cold-Formed Steel Structural Members provides a design procedure to address web crippling, those design rules were developed for members whose cross sections are different from that of V-core panels. Consequently, nine specimens were tested to collect data on V-core panels subjected to end one-flange loading. Test observations suggested that V-core panels behave very similarly to multi-web decks that are strapped and unfastened to the supports. Experimental data reported in the literature was used to modify the web crippling strength equation in the Specification to reflect these particular conditions. The modified equation was found to adequately predict the measured web crippling strength of V-core panels.