Web-Crippling Strength of Multi-Web Cold-Formed Steel Deck Sections Subjected to End One Flange (EOF) Loading

The AISI (1996) Specification for the Design of Cold-Formed Steel Structural Members provisions for web-crippling are believed to be conservative for multi-web deck sections. They are based on unfastened specimens and are limited to the use of decks with certain geometric parameters. The unified web crippling equation of the North American (2002) Specification for the Design of Cold-Formed Steel Structural Members (adopted from Canadian S136-94 Specification) is also limited to certain geometric parameters. Although it has new web crippling coefficients for different load cases and different end conditions, in the End One Flange (EOF) loading case, coefficients for the unfastened configuration were used as a conservative solution for the fastened case because there was no directly applicable test data available in the literature.

This thesis presents the results of an experimental study on web-crippling strength of multiple-web cold-formed steel deck sections subjected to End One Flange (EOF) loading. Seventy-eight tests were conducted at Virginia Tech. Test specimens lying inside and outside of certain geometric parameters of the specifications were tested with both unrestrained and restrained end conditions. Test specimens lying inside the specification parameters have revealed conservative results in the prediction of web crippling capacity using both AISI (1996) and North American (2002) equations. Using the unified web-crippling equation of North American Specification, a nonlinear regression analysis was performed to update the unfastened case coefficients and derive new fastened case coefficients. Also, the calibration of these coefficients is done for both Canadian S136 (1994) and AISI (1996) specifications.