TablesK Additional requirements for HSS and box-section connections
Round HSS
PDF page 234 · AISC 360-22
3 tables appear under this heading.
1. PDF page 234
| Width ratio: | Bb / B and Hb / B ≥ 0.1 + γ / 50 |
| βeff ≥ 0.35 | |
| Gap ratio: | ξ = g/B ≥ 0.5(1-βeff) |
| Gap: | g ≥ tb compression branch + tb tension branch |
| Branch size: | smaller Bb ≥ 0.63(larger Bb), if both branches are square |
2. PDF page 235
| TABLE K4.1 Available Strengths of Round HSS-to-HSS Moment Connections | |
|---|---|
| Connection Type | Connection Available Flexural Strength |
| Branch(es) under in-plane bending T-, Y-, and cross-connections [Diagram of in-plane bending connection: Shows a round HSS chord with a branch HSS welded to it at an angle, illustrating dimensions M, Db, tb, θ, t, D] | Limit state: chord plastification Mn-ip = 5.39Fyt20.5β (Db/sinθ) Qf (K4-1) φ = 0.90 (LRFD) Ω = 1.67 (ASD) |
| Limit state: shear yielding (punching), when Db < (D-2t) Mn-ip = 0.6FytDb2 ((1+3sinθ)/(4sin2θ)) (K4-2) φ = 0.95 (LRFD) Ω = 1.58 (ASD) | |
| Branch(es) under out-of-plane bending T-, Y-, and cross-connections [Diagram of out-of-plane bending connection: Shows a round HSS chord with a branch HSS welded perpendicular to it, illustrating dimensions M, Db, tb, t, D] | Limit state: chord plastification Mn-op = (Fyt2Db/sinθ) ((3.0)/(1-0.81β)) Qf (K4-3) φ = 0.90 (LRFD) Ω = 1.67 (ASD) |
| Limit state: shear yielding (punching), when Db < (D-2t) Mn-op = 0.6FytD2 ((3+sinθ)/(4sin2θ)) (K4-4) φ = 0.95 (LRFD) Ω = 1.58 (ASD) | |
| For T-, Y-, and cross-connections, with branch(es) under combined axial load, in-plane bend-ing, and out-of-plane bending, or any combination of these load effects Pr/Pc + (Mr-ip/Mc-ip)2 + Mr-op/Mc-op ≤ 1.0 (K4-5) Pr = required axial strength in branch using LRFD or ASD load combinations, kips (N) Mr-ip = required in-plane flexural strength in branch using LRFD or ASD load combinations, kip-in. (N-mm) Mr-op = required out-of-plane flexural strength in branch using LRFD or ASD load combinations, kip-in. (N-mm) Pc = available axial strength obtained from Table K3.1, kips (N) Mc-ip = available strength for in-plane bending, kip-in. (N-mm) Mc-op = available strength for out-of-plane bending, kip-in. (N-mm) | |
3. PDF page 236
| TABLE K4.1A Limits of Applicability of Table K4.1 | |
|---|---|
| Chord wall slenderness: | D/t ≤ 50 for T- and Y-connections D/t ≤ 40 for cross-connections |
| Branch wall slenderness: | Db/tb ≤ 50 0.05E/Fyb ≤ Db/tb |
| Width ratio: | 0.2 < Db/D ≤ 1.0 |
| Material strength: | Fy and Fyb ≤ 52 ksi (360 MPa) |
| Ductility: | Fy/Fu and Fyb/Fub ≤ 0.8 Note: ASTM A500/A500M Grade C is acceptable. |