AISC 360-22 Shear Tab Connection Glossary
Definitions of the terms used across shearcheck's verification, methodology pages, and calculation output, in the sense ANSI/AISC 360-22 uses them for conventional single-plate shear connections.
Shear tab (single-plate connection)
A simple shear connection made from one plate, welded to the supporting member and bolted to the beam web, that transfers the beam's end reaction in shear while letting the beam end rotate. Its economy — one plate, one bolt row, all bolting done on the beam side — makes it one of the most common steel connections in buildings. shearcheck checks this connection type per AISC 360-22.
Conventional configuration
The standardized shear tab layout that permits the simplified design procedure: a single vertical bolt row, limited distance a from weld line to bolt line, plate fillet-welded both sides to a rigid support, with the eccentricity taken as e = a/2 and a plate-thickness cap of db/2 + 1/16 in — as illustrated in AISC Design Examples v16.0, Example II.A-17A. Connections outside these limits fall to the "extended configuration," which requires additional checks outside shearcheck's V1 scope. See why e = a/2.
Block shear rupture
A failure mode where a block of plate tears out along the bolt line: shear failure along the vertical path through the holes combined with tension failure on the perpendicular path to the plate edge. AISC 360-22 Eq. J4-5 takes the lesser of shear yielding and shear rupture on the shear path, plus tension rupture (with the uniform-tension factor Ubs) on the tension path. In the verified demo case it is one of the closer non-governing states (φRn ≈ 65.5 kips).
Bearing vs tearout
Two per-bolt limit states at each hole, per AISC 360-22 §J3.11a: bearing (Eq. J3-6a, 2.4·d·t·Fu) limits the hole-wall crushing force, while tearout (Eq. J3-6c, 1.2·lc·t·Fu) limits the force that would rip the bolt through the clear distance lc to the next hole or the plate edge. The bolt nearest a free edge is usually tearout-controlled; interior bolts are usually bearing-controlled — shearcheck evaluates both at every position, in both the plate and the beam web.
Thread condition (N / X)
Whether the bolt's threads are iNcluded in (N) or eXcluded from (X) the shear plane. Threads reduce the shank area available to resist shear, so AISC 360-22 Table J3.2 assigns lower nominal stresses to N — for Group 120 bolts, Fnv = 54 ksi (N) vs 68 ksi (X). N is the common default assumption because it is safe regardless of how the bolt seats; X may be used when detailing ensures the threads clear the faying surface.
ICR method (instantaneous center of rotation)
The ultimate-strength method for eccentrically loaded bolt groups: the group rotates about an instantaneous center, each bolt's force follows the experimental load-deformation law R = Rult(1 − e−10Δ)0.55 with Δmax = 0.34 in, and iteration locates the center where the forces balance the load. The result is the coefficient C — the group's effective number of bolts. shearcheck implements the iterative procedure published in Brandt (AISC Engineering Journal, Q2 1982); see the full explainer.
LRFD vs ASD
The two design formats of AISC 360-22. LRFD compares factored loads against φRn (resistance factor times nominal strength); ASD compares service-level loads against Rn/Ω (nominal strength over a safety factor). Each limit state carries its own pair — e.g. φ = 0.75 / Ω = 2.00 for bolt shear and plate shear rupture, φ = 1.00 / Ω = 1.50 for shear yielding. shearcheck reports both formats on every check.
Effective hole (B4.3b)
For net-area calculations, AISC 360-22 §B4.3b requires the hole to be taken 1/16 in larger than its nominal dimension, accounting for punching damage around the hole edge. A 3/4-in bolt in a standard 13/16-in hole (Table J3.3) therefore removes 7/8 in of material per hole from net shear and tension areas — the value behind the demo case's Anv = 2.00 in² in the worked example.
Governing limit state
The limit state with the smallest available strength — the one that sets the connection's capacity and the one a strengthening change must address first. A connection is checked against every applicable limit state (bolt group, bearing/tearout, plate shear yield and rupture, block shear, weld), and the governing state can differ between LRFD and ASD because φ and Ω pairs are not proportional. shearcheck highlights the governing state on every result page.
Workable flat (T)
The flat portion of a W-shape's web between the fillets at the flanges — the depth actually available for attaching a plate. Listed as T in the AISC Shapes Database (13.625 in for a W16×50). A shear tab's plate depth must fit within the workable flat; shearcheck checks this dimensional rule automatically from the Shapes Database v16.0 values.