Direct Answer
A shear tab (or single-plate shear connection) is a standard simple beam connection where a vertical plate is shop-welded to the supporting member (column or girder web) and field-bolted to the supported beam web. It transfers shear only — not moment. It is by far the most common beam-to-column connection in commercial steel construction because it is economical, fast to fabricate, and fast to erect.
Full Explanation
The shear tab plate is typically A36 or A572 Gr 50, sized per AISC Design Guide 10 or the engineer's design. Bolt count (typically 2–7 bolts) and plate dimensions depend on the reaction load. Shear tabs can be configured as 'conventional' (plate extends only to the beam web) or 'extended' (plate extends beyond the beam flange to handle larger loads). The tab is shop-welded to the support with a CJP or fillet weld and field-bolted to the beam web. Single-plate connections offer some limited rotation capacity, which is important for composite floor systems.
What This Means for Your Shop
Shear tab orientation matters: confirm 'near side' vs. 'far side' in your shop drawings. A shear tab on the wrong face of a column will not match the beam in the field. Also confirm whether the tab is shop-welded (fabricated as part of the column assembly) or field-welded (attached on site).
Common Mistakes
Attaching a shear tab to the wrong face of a column web — a symmetric column looks the same from either side, but the connection bay orientation is specific. Mark columns with their orientation reference before leaving the shop.
Recommended Process
During layout, mark the 'North' or 'erection mark' face of every column. Verify shear tab orientation against the erection drawing before welding. Inspect all shear tabs for correct location and dimension before shipping.