Predesigned Bolted Framing Angle Connections

The current AISC Specification provisions governing the use of mechanical fasteners in structural applications are largely based upon rational rules provided in Guide to Design Criteria for Bolted and Riveted Joints by Fisher and Struik. This publication was sponsored by the Research Council on Structural Connections to evaluate and distill the results of voluminous research in this field that has been conducted since the late 1800s. Unfortunately, adoption of rules which provide the designer with an improved basis for understanding and estimating the real strength of structural connections has made connection design more complex. There are several modes of failure, any one of which may control the strength of a connection, and each must be considered. Thus, the design or checking of a given connection has become more demanding than in the past, when Specification provisions masked the true performance of connections behind overly conservative rules which addressed only a few possible modes of failure. For a complete framing angle connection design, the following must be considered: bolt shear, bearing on connected material, edge distance, block shear, net section shear, connection length, bolt spacing, slip resistance, hole size and shape and, in some cases, other special factors.