Evolution of Shear Lag and Block Shear Provisions in the AISC Specification

The American Institute of Steel Construction (AISC) has published two standards for design of steel structures for the past 19 years, an allowable stress specification, ASD, and a limit states specification, LRFD. The AISC Committee on Specifications has developed a new standard that includes provisions for design according to both ASD and LRFD. For connection design, the specification evolved as provisions from the previous specifications were integrated into the new provisions. This paper highlights the provisions for shear lag and block shear from the 2005 AISC Specification for Structural Steel Buildings provisions and the changes that have taken place from previous editions of the specifications.