8-Panel Symmetric Pratt Roof Truss
16 m symmetric Pratt roof truss with 7 panel-point loads (40 kN each); teaches Pratt load-path pattern where verticals compress and diagonals tension, and identifies the zero-force apex vertical by bilateral symmetry.
Category: truss · Difficulty: Intermediate
Solution
| Support | Rx (N) | Ry (N) | Mz (N·m) |
|---|---|---|---|
| L0 | 0 | 140 | 0 |
| L8 | 0 | 140 | 0 |
| Member | Axial force (N) | Sense |
|---|---|---|
| Member 17 | 280 | Tension |
| Member 18 | 240 | Tension |
| Member 19 | 200 | Tension |
| Member 20 | 160 | Tension |
| Member 21 | 160 | Tension |
| Member 22 | 200 | Tension |
| Member 23 | 240 | Tension |
| Member 24 | 280 | Tension |
| Member 25 | -313.05 | Compression |
| Member 26 | -313.05 | Compression |
| Member 27 | -268.328 | Compression |
| Member 28 | -223.607 | Compression |
| Member 29 | -223.607 | Compression |
| Member 30 | -268.328 | Compression |
| Member 31 | -313.05 | Compression |
| Member 32 | -313.05 | Compression |
| Member 33 | -40 | Compression |
| Member 34 | -60 | Compression |
| Member 35 | -80 | Compression |
| Member 36 | 0 | — |
| Member 37 | -80 | Compression |
| Member 38 | -60 | Compression |
| Member 39 | -40 | Compression |
| Member 40 | 56.569 | Tension |
| Member 41 | 72.111 | Tension |
| Member 42 | 89.443 | Tension |
| Member 43 | 89.443 | Tension |
| Member 44 | 72.111 | Tension |
| Member 45 | 56.569 | Tension |
All reaction values are computed by the StatIQ structural engine, not generated text. Signs follow the solver's convention: a positive Ry acts upward, a negative Ry downward; a positive M is counter-clockwise.