Designing moment connections

Transcript

Designing moment connections in ILX Connection.

Two kinds of moment connection

The Moment group of the new connection wizard has two cards. FR moment is fully restrained: the beam flanges carry the moment straight into the column. PR moment is partially restrained, with top and seat angles.

FR configurations

Select FR moment, and pick one of three configurations. Bolted flange plates are welded to the column and bolted to the beam flanges. Welded flange plates are fillet-welded to the beam instead. Directly welded flanges are groove-welded to the column, with a bolted shear tab for the web.

Members and loads

On the Members step, enter the beam and the column: a W18x50 beam into a W14x61 column. On the Loads step, enter the dead and live moments, then the dead and live shears. A positive moment puts the top flange in tension. Column stiffeners and doublers are designed for you when they are needed.

The editor

The editor shows the inputs, the status and the drawings together. The key data strip lists the flange plates, the flange force, the stiffeners and the doubler. Open Required strength and flange forces to see how the moment becomes a pair of flange forces.

Flange plates and bolts

The Flange plates section sets the top and bottom plates and their welds to the column. The Bolts section sets the bolt size, the rows along each flange and their spacing.

Column-side checks

Moment connections often depend on the column. At each flange force, ILX checks the column flange in bending, the web in local yielding and crippling, and the panel zone in shear. The Column section holds the column forces and the stiffener and doubler options.

Without stiffeners

To see why the stiffeners are there, set Transverse stiffeners and Web doubler to None. The status turns red. The column flange is too thin for the tension flange force, and the panel zone is overstressed. Select the Failed filter to list just the failing checks.

Stiffeners and doublers

Set both back to Design when required. ILX adds a pair of stiffeners at each flange and a web doubler, sizes them, and checks their welds. The sizes appear in the key data strip and in the drawings, and the connection is adequate again. Suggested fixes let you keep the designed sizes with one click.

Directly welded flanges

Switch to Directly welded, and the same column checks apply to the groove-welded flanges. The weld access holes are detailed for you.

PR moment

For a partially restrained connection, choose PR moment. The top and seat angles are bolted to the column, and bolted or welded to the beam flanges. Double web angles carry the shear.

PR checks

ILX checks the angles for prying and bending, the bolts, and the same column checks at the angles. The Stiffness and classification section estimates the connection's stiffness, and confirms that it really behaves as partially restrained.

Summary

Pick the configuration, enter the beam, the column and the loads, and watch the column-side checks. Let ILX design the stiffeners and doublers, then create the report and the drawing sheet.

The user manual covers every option. Try it at ilxconnection.com. ILX Studio, LLC is not affiliated with AISC.