Direct Answer
A double angle connection uses two steel angles (one on each side of the beam web) shop-bolted or welded to the support and field-bolted to the beam web. It is a standard simple beam connection, similar to a shear tab, but provides more shear capacity for a given depth and is commonly used where shear tabs are insufficient or where the connection must transfer shear from both sides of a web.
Full Explanation
Double angle connections are designed per AISC Manual Table 10-1. The angles are typically 2L3×3×3/8 or 2L4×4×1/2 (AISC designation) with standard bolt spacing. They can be framed: short legs outstanding (angles vertical against the support), or long legs outstanding. Short-leg-outstanding is more common. Weld connecting the angles to the support or bolt connecting (WT connection) depends on the design. Double angles are more complex to fabricate than shear tabs but provide better flexibility for different connection conditions.
What This Means for Your Shop
Double angle connections are a higher labor item than shear tabs: two angles must be precisely spaced and aligned. Misalignment by 1/16" can prevent the field bolt from fitting through all plies (angle + beam web + angle). Verify gage distance carefully on the shop drawing.
Common Mistakes
Misaligning the two angles relative to each other so the bolt holes don't line up. This is especially common when angles are attached by welding (which can cause distortion) rather than bolting.
Recommended Process
Use a jig or fixture when welding double angle connections to maintain precise angle spacing. After welding, check that a bolt passes cleanly through both angles before the assembly leaves the welding station.