Shear Stud / Shear Connector

A shear stud (also called shear connector or headed stud) is a welded steel pin that transfers horizontal shear force between a steel beam and an overlying concrete slab in composite construction. Welded onto the top flange of the steel beam at specified spacing, the studs project up into the concrete slab and engage the slab via mechanical bond and bearing. The combination of steel beam + concrete slab acts as a composite beam with significantly higher moment capacity and stiffness than steel beam alone — typical capacity increase 20-40% and stiffness increase 30-50%.

Indian codes: IS 11384:2022 (composite construction with steel beams and reinforced concrete slabs) — the primary code, replacing IS 11384:1985. Companion: IS 800:2007 Section 12 (composite construction). For shear stud specification: typical Indian sizes are 16 mm, 19 mm, 22 mm, 25 mm diameter with heights 75-150 mm. The stud capacity per IS 11384 Cl. 8 is the lesser of: (a) stud-shaft yield, (b) concrete bearing capacity at the stud head, computed as Ph = 0.4 × (fck × Es)^0.5 × ds² + 0.4 × hs × ds × fck for single shear. For 19 mm stud × 100 mm height in M30 concrete: capacity ≈ 95 kN per stud.

Indian site execution: studs are welded with stud-welding equipment (drawn-arc method, IS 11384 Cl. 9) — a charged stud is held against the beam flange and drawn-arc welded with substantial current. Each weld takes about 1 second; production rate 20-30 studs per minute on a clean flange. The most critical site QC is weld inspection — visual check for full ring of weld bead around the stud base, plus spot bend test on one stud per 50 (the stud must bend 30° without weld failure). Failed studs are removed by oxy-cutting and re-welded. Major Indian users of shear studs: composite floor construction in office buildings (12-50 storey), metro stations, airport terminals, and steel-girder bridge decks per IRC 24.