Plan View: Must show the modular panel layout, internal reinforcement (tie rods), and overall footprint dimensions.
Tank Sizing: Recommended sizing should meet local fire codes plus an additional 2 days of supply for irrigation and household needs.
A GRP (Glass Reinforced Plastic) water tank AutoCAD drawing typically includes comprehensive technical details for modular, sectional tanks
- Water depth (H): The nominal height (e.g., 1.5m, 2m, 3m).
- Freeboard: The empty space between the water level and the roof (usually 200–300mm) to prevent hydraulic pressure on the lid.
- Side panel stiffeners: GRP panels flex; the drawing must show horizontal and vertical stiffener ribs or external steel sections.
- Floor slope: Drawings must indicate a slope towards the outlet flange to facilitate complete drainage (often 1:100 gradient).
3. Drafting Standards and Layers
To ensure the drawing is readable by consultants and contractors, specific AutoCAD standards are applied:
- Plinth beams: Reinforced concrete beams under the panel joints.
- Void space: GRP tanks are usually elevated slightly (100–200mm) above the blinding concrete to allow visual inspection of the base panel and prevent ground moisture seepage.
5. 2D vs. 3D Modeling
While traditional 2D