Experiments on Rotational Restraint of Sheathing

Abstract

A series of cantilever tests on joist-sheathing assemblies were conducted to determine the rotational restraint that sheathing provides to the compression flange of a floor joist in bending. This rotational restraint, which is characterized by the stiffness k?, can partially or fully retard distortional buckling. Distortional buckling is a mode of instability in which the flange undergoes rotation about the flange/web juncture of a member and the web locally bends. This mode of buckling has recently been recognized as a separate strength limit state in the North American Specification and design rules for its prediction adopted.