1. Project
Demo — 12 m 3D box truss (CSA S16-19) · rev A
| Project number | TD3D-001 |
| Client | Demonstration |
| Designer / checker | — / — |
| Date | 2026-01-01 |
| Steel grade | CSA G40.21 350W |
| Fy / Fu (MPa) | 350 / 450 |
| E / G (MPa) | 200000 / 77000 |
| φ / φu | 0.9 / 0.75 |
2. Model
20 joints · 48 members · 4 supports
3. Loads
NBCC 2020 derivation
| Dead qD (kPa) | 1.5 | Live qL (kPa) | 1 |
| Snow S (kPa) | 1.8000 | Wind p (kPa) | -0.6075 |
| Panel spacing a (m) | 3 | Truss spacing B (m) | 10 |
4. Governing member checks
44 PASS · 4 FAIL
| Mbr | Role | Section | Class | Combo | Cf (kN) | Tf (kN) | Mfx (kNm) | DCR | Status |
|---|---|---|---|---|---|---|---|---|---|
| 13 | Vertical | L76x76x7.9 | 3 | ULS3a | 171.94 | 0.00 | 1.550 | 1.100 | FAIL |
| 9 | Vertical | L76x76x7.9 | 3 | ULS3a | 171.93 | 0.00 | 1.550 | 1.100 | FAIL |
| 26 | Vertical | L76x76x7.9 | 3 | ULS3a | 171.98 | 0.00 | 1.552 | 1.078 | FAIL |
| 30 | Vertical | L76x76x7.9 | 3 | ULS3a | 171.97 | 0.00 | 1.552 | 1.077 | FAIL |
| 27 | Vertical | L76x76x7.9 | 3 | ULS3a | 125.61 | 0.00 | 1.029 | 0.789 | PASS |
| 29 | Vertical | L76x76x7.9 | 3 | ULS3a | 125.61 | 0.00 | 1.029 | 0.789 | PASS |
| 40 | Bottom Strut | L76x76x7.9 | 3 | ULS4b | 0.00 | 3.52 | 1.894 | 0.775 | PASS |
| 10 | Vertical | L76x76x7.9 | 3 | ULS3a | 125.51 | 0.00 | 1.029 | 0.771 | PASS |
| 12 | Vertical | L76x76x7.9 | 3 | ULS3a | 125.51 | 0.00 | 1.029 | 0.771 | PASS |
| 44 | Bottom Strut | L76x76x7.9 | 3 | ULS4b | 0.00 | 3.47 | 1.865 | 0.763 | PASS |
| 45 | Top Bracing | L76x76x7.9 | 3 | ULS1 | 0.97 | 0.00 | 0.127 | 0.745 | PASS |
| 46 | Top Bracing | L76x76x7.9 | 3 | ULS1 | 1.94 | 0.00 | 0.110 | 0.745 | PASS |
| 47 | Top Bracing | L76x76x7.9 | 3 | ULS1 | 1.93 | 0.00 | 0.110 | 0.745 | PASS |
| 48 | Top Bracing | L76x76x7.9 | 3 | ULS1 | 0.97 | 0.00 | 0.128 | 0.745 | PASS |
| 31 | Diagonal | L102x76x9.5 | 4 | ULS3a | 0.00 | 279.80 | 0.361 | 0.636 | PASS |
| 33 | Diagonal | L102x76x9.5 | 4 | ULS3a | 0.00 | 279.79 | 0.361 | 0.636 | PASS |
| 16 | Diagonal | L102x76x9.5 | 4 | ULS3a | 0.00 | 279.40 | 0.364 | 0.630 | PASS |
| 14 | Diagonal | L102x76x9.5 | 4 | ULS3a | 0.00 | 279.39 | 0.364 | 0.630 | PASS |
| 35 | Top Strut | L76x76x7.9 | 3 | ULS4b | 2.37 | 0.00 | 1.879 | 0.516 | PASS |
| 39 | Top Strut | L76x76x7.9 | 3 | ULS4b | 2.33 | 0.00 | 1.851 | 0.509 | PASS |
| 15 | Diagonal | L102x76x9.5 | 4 | ULS1 | 0.00 | 40.02 | 0.230 | 0.478 | PASS |
| 17 | Diagonal | L102x76x9.5 | 4 | ULS1 | 0.00 | 40.02 | 0.230 | 0.478 | PASS |
| 32 | Diagonal | L102x76x9.5 | 4 | ULS1 | 0.00 | 39.60 | 0.230 | 0.478 | PASS |
| 34 | Diagonal | L102x76x9.5 | 4 | ULS1 | 0.00 | 39.60 | 0.230 | 0.478 | PASS |
| 36 | Top Strut | L76x76x7.9 | 3 | ULS4a | 1.50 | 0.00 | 0.523 | 0.413 | PASS |
| 38 | Top Strut | L76x76x7.9 | 3 | ULS4a | 1.51 | 0.00 | 0.514 | 0.413 | PASS |
| 41 | Bottom Strut | L76x76x7.9 | 3 | ULS4b | 0.00 | 0.11 | 0.772 | 0.392 | PASS |
| 43 | Bottom Strut | L76x76x7.9 | 3 | ULS4b | 0.00 | 0.10 | 0.760 | 0.386 | PASS |
| 11 | Vertical | L76x76x7.9 | 3 | ULS3a | 85.44 | 0.00 | 1.60e-5 | 0.376 | PASS |
| 1 | Bottom Chord | W200x36 | 2 | ULS4a | 0.14 | 0.00 | 1.880 | 0.367 | PASS |
| 4 | Bottom Chord | W200x36 | 2 | ULS4a | 0.44 | 0.00 | 1.881 | 0.367 | PASS |
| 28 | Vertical | L76x76x7.9 | 3 | ULS3a | 85.01 | 0.00 | 1.25e-5 | 0.358 | PASS |
| 7 | Top Chord | W200x46 | 3 | ULS3a | 338.19 | 0.00 | 9.352 | 0.355 | PASS |
| 6 | Top Chord | W200x46 | 3 | ULS3a | 338.18 | 0.00 | 9.352 | 0.355 | PASS |
| 24 | Top Chord | W200x46 | 3 | ULS3a | 337.78 | 0.00 | 9.316 | 0.355 | PASS |
| 23 | Top Chord | W200x46 | 3 | ULS3a | 337.78 | 0.00 | 9.316 | 0.355 | PASS |
| 5 | Top Chord | W200x46 | 3 | ULS1 | 103.39 | 0.00 | 3.522 | 0.294 | PASS |
| 8 | Top Chord | W200x46 | 3 | ULS1 | 103.39 | 0.00 | 3.522 | 0.294 | PASS |
| 22 | Top Chord | W200x46 | 3 | ULS1 | 104.34 | 0.00 | 3.610 | 0.294 | PASS |
| 25 | Top Chord | W200x46 | 3 | ULS1 | 104.34 | 0.00 | 3.610 | 0.294 | PASS |
| 37 | Top Strut | L76x76x7.9 | 3 | ULS1 | 0.00 | 0.99 | 0.046 | 0.275 | PASS |
| 42 | Bottom Strut | L76x76x7.9 | 3 | ULS1 | 0.00 | 0.08 | 0.077 | 0.275 | PASS |
| 2 | Bottom Chord | W200x36 | 2 | ULS1 | 0.00 | 104.66 | 3.147 | 0.244 | PASS |
| 3 | Bottom Chord | W200x36 | 2 | ULS1 | 0.00 | 104.65 | 3.147 | 0.244 | PASS |
| 18 | Bottom Chord | W200x36 | 2 | ULS1 | 0.00 | 0.88 | 2.805 | 0.244 | PASS |
| 19 | Bottom Chord | W200x36 | 2 | ULS1 | 0.00 | 104.99 | 3.133 | 0.244 | PASS |
| 20 | Bottom Chord | W200x36 | 2 | ULS1 | 0.00 | 104.99 | 3.133 | 0.244 | PASS |
| 21 | Bottom Chord | W200x36 | 2 | ULS1 | 0.00 | 0.89 | 2.805 | 0.244 | PASS |
5. Serviceability
| SLS combo | max |uZ| (mm) | Limit (mm) | DCR | Status |
|---|---|---|---|---|
| SLS1 | 8.2385 | 33.33 | 0.247 | PASS |
| SLS2 | 10.1161 | 33.33 | 0.303 | PASS |
6. Limitations
- Linear-elastic first-order analysis; no second-order (P-Δ) or geometric non-linearity.
- Prismatic 12-DOF frame elements; rigid joints with no eccentricity or panel-point slip.
- Connections, base plates, bracing details and fatigue are not designed.
- Lateral-torsional buckling is covered only through the Cl. 13.8.2 terms used here.
- Loads are derived from the user-entered NBCC coefficients; site-specific values must be confirmed.
- Output must be reviewed and sealed by a qualified professional engineer.