Crippling capacity of web elements with openings

Commonly used cold-formed steel sections utilized as either wall studs or f loor joists contain web holes. The web holes may be factory punched or fiel d cut. Because the Specification for the Design of Cold-Formed Steel Struct ural Members does not address the potential impact that a web hole can have on the structural integrity of the cold-formed steel member, research was necessary. Researchers at the University of Missouri-Rolla have explored th e behavior of a flexural member that possesses a web hole. The scope of the UMR research includes flexure, shear, web crippling, and combinations ther eof. The present paper will summarize the findings and design recommendatio ns pertaining to web crippling resulting from either end-one-flange or inte rior-one-flange loading. The research determined that the paramount factors influencing the web crippling behavior were the relationship between the h ole depth and the depth of the web and the relationship between the distanc e from the edge of the bearing and the flat depth of the web. Easily applie d design relationships have been developed.