Seastead Design: Model and Full-Scale Dimensions
Based on a 1/6 scale model with Froude scaling rules. The triangle above water has a side length of 10 ft at model scale (60 ft full scale). Three cylindrical legs (5-inch diameter, 6 ft long at model scale) extend from each corner at a 45° angle, with approximately 60% of each leg submerged. Seawater density is taken as 64 lb/ft³.
Dimensions
| Component |
Model Scale (1/6) |
Full Scale (λ = 6) |
| Triangle side length |
10 ft |
60 ft |
| Leg length |
6 ft |
36 ft |
| Leg diameter |
5 inches (0.4167 ft) |
2.5 ft (30 inches) |
| Leg angle from horizontal |
45° |
45° |
| Horizontal projection per leg |
4.24 ft |
25.46 ft |
| Vertical drop per leg |
4.24 ft |
25.46 ft |
Buoyancy and Weight
Froude Scaling: Length scale λ = 6, force/weight scale = λ³ = 216.
Displaced volume scales with λ³, so weight scales with λ³.
| Parameter |
Model Scale |
Full Scale |
| Submerged volume per leg |
0.491 ft³ |
106.0 ft³ |
| Total displaced volume |
1.473 ft³ |
318.1 ft³ |
| Displaced water weight (buoyant force) |
30π lb ≈ 94.25 lb |
6480π lb ≈ 20,358 lb |
| Target total weight of structure |
94.25 lb |
20,358 lb |
Notes:
- Submerged fraction of each leg is 60% by volume (i.e., 60% of leg length submerged along its axis).
- Weight includes the triangle platform, legs, ropes, and all other components.
- Full-scale dimensions are obtained by multiplying model dimensions by λ = 6.
- Seawater density is approximated as 64 lb/ft³. For precise design, use local seawater density.
- Ropes (two per leg to adjacent corners) are for structural support and do not contribute significantly to buoyancy.
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