Concrete Shear Wall Design
Reinforced concrete structural walls per ACI 318-19. In-plane shear (§11.5.4), axial-flexure P-M interaction by strain compatibility, minimum reinforcement and detailing (§11.6/§11.7), simplified axial strength (§11.5.3) and special boundary-element triggers (§18.10.6) — with the full interaction diagram and demand point. US units (kips, kip·ft, psi, in).
Axial-flexure interaction Ch. 22 · §11.5.2
| φPn,max | 5,735.8 k | 0.65·0.80·Po |
| φMn at Pu | 17,308.6 k·ft | |
| Demand (Pu, Mu) | 800.0, 12,000.0 k, k·ft | |
| Ast (total vert.) | 21.9 in² | |
| Utilisation Mu/φMn | 0.69 |
In-plane shear 11.5.4
| Acv = h·lw | 2,880 in² | |
| αc (hw/lw) | 2.00 | |
| Vn | 1,108.3 k | |
| φVn | 831.2 k | φ = 0.75 |
| Demand Vu | 500.0 k |
Minimum reinforcement §11.6 / §11.7
| ρl provided / min | 0.431 / 0.295% | |
| ρt provided / min | 0.431 / 0.250% | |
| Curtains required | 2 | Vu > 2λ√f′c·Acv; h > 10 in |
| Max spacing | 18 in |
Simplified axial §11.5.3
| φPn (k·lc/32h, k=0.8) | 3,747.7 k | φ = 0.65 |
| Demand Pu | 800.0 k | |
| Utilisation | 0.21 | e ≤ h/6 |
ACI 318-19 (LRFD). Rectangular structural wall — in-plane shear (§11.5.4), axial-flexure P-M interaction (Ch. 22 strain compatibility), minimum reinforcement (§11.6/§11.7), simplified axial (§11.5.3) and, for special walls, boundary-element triggers (§18.10.6). Diaphragm/collector forces, sliding shear-friction, coupling beams, out-of-plane slenderness and foundation design are not included. Factored demands and δu are user inputs. A licensed P.E. review remains required.