Prepared by the Task Committee on Effective Length of the Technical Committee on Load and Resistance Factor Design of the Structural Engineering Institute of ASCE, this report provides a thorough understanding of the strengths, limitations, and assumptions regarding column and frame stability as defined in the AISC Load and Resistance Factor Design Specification for Structural Steel Buildings (LRFD), Second Edition (1993).
The document focuses on three techniques for stability design. Two approaches are based on the use of effective length factors and are specifically outlined in the Commentary of the AISC specifications. The third method involves the use of a notional load approach, employing an effective length factor equal to one for all columns in the frame. Although notional load approaches are not mentioned in the AISC specifications, this technique is commonly used in some form within several other design standards throughout much of the rest of the world.
Examples illustrate the procedures for both common and unusual conditions encountered in practice. The document is applicable to both unbraced and braced frames having either fully restrained or partially restrained connections. A practical introduction is provided through discussions of the assumptions, advantages, and disadvantages of each method, along with step-by-step examples, while more detailed discussions and derivations address complex issues involved with design for stability.
Description:
Prepared by the Task Committee on Effective Length of the Technical Committee on Load and Resistance Factor Design of the Structural Engineering Institute of ASCE, this report provides a thorough understanding of the strengths, limitations, and assumptions regarding column and frame stability as defined in the AISC Load and Resistance Factor Design Specification for Structural Steel Buildings (LRFD), Second Edition (1993).
The document focuses on three techniques for stability design. Two approaches are based on the use of effective length factors and are specifically outlined in the Commentary of the AISC specifications. The third method involves the use of a notional load approach, employing an effective length factor equal to one for all columns in the frame. Although notional load approaches are not mentioned in the AISC specifications, this technique is commonly used in some form within several other design standards throughout much of the rest of the world.
Examples illustrate the procedures for both common and unusual conditions encountered in practice. The document is applicable to both unbraced and braced frames having either fully restrained or partially restrained connections. A practical introduction is provided through discussions of the assumptions, advantages, and disadvantages of each method, along with step-by-step examples, while more detailed discussions and derivations address complex issues involved with design for stability.