PREFACE

This document provides a commentary on the 2007 edition of the North American Specification for the Design of Cold-Formed Steel Structural Members. This Commentary should be used in combination with the 2008 edition of the AISI Cold-Formed Steel Design Manual.

The purpose of the Commentary includes: (a) to provide a record of the reasoning behind, and justification for the various provisions of the North American Specification by cross-referencing the published supporting research data and to discuss the changes make in the current Specification; (b) to offer a brief but coherent presentation of the characteristics and performance of cold-formed steel structures to structural engineers and other interested individuals; (c) to furnish the background material for a study of cold-formed steel design methods to educators and students; and (d) to provide the needed information to those will be responsible for future revisions of the Specification. The readers who wish to have more complete information, or who may have questions which are not answered by the abbreviated presentation of this Commentary, should refer to the original research publications.

Consistent with the Specification, the Commentary contains a main document, Chapters A through G, and Appendices 1 and 2, and Appendices A and B. A Symbol A,B is used in the main document to point out that additional discussions are provided in the corresponding country specific provisions in Appendices A and/or B.

The Assistance and close cooperation of the North American Specification Committee under the Chairmanship of Professor Reinhold M. Schuster and the AISI Committee on Specifications under the Chairmanship of Mr. Roger L. Brockenbrough and the Vice Chairmanship of Mr. Jay W. Larson are gratefully acknowledge. Special thanks are extended to Professor Wei-Wen Yu for revising the draft of this Commentary. The Institute is very grateful to members of the editorial Subcommittee and all members of the AISI Committee on Specifications for their careful review of the document and thei valuable comments and suggestions. The background materials provided by various subcommittees are appreciated.