Water tank foundation and details
The foundation design and details of the water tank directly affect its stability, service life and whether it leaks. The following is a detailed description of the foundation and key details of the FRP water tank:

I. Key points of foundation design

Choose foundation type

Concrete foundation:

Applicable to ground installation, it is necessary to cast a reinforced concrete slab with a thickness of ≥150mm and a strength grade of ≥C20.

The foundation area should be slightly larger than the bottom area of ​​the water tank (50~100mm is reserved around) to ensure uniform load-bearing.

Channel steel/I-beam bracket:

Applicable to roof or overhead installation, the steel needs to be rust-proofed (such as hot-dip galvanizing), and the span is ≤1.5m to prevent deformation of the bottom of the water tank.

Load-bearing requirements

The foundation must be able to withstand the total weight of the water tank when fully loaded (water weight + tank weight).

Calculation formula: Total load = water tank volume (m³) × water density (1 ton/m³) + water tank dead weight (usually 0.2~0.5 tons/m³).

Levelness requirements

The horizontal error of the foundation surface should be ≤3mm/m to avoid stress concentration caused by tilting of the water tank after installation.

Use a level to calibrate, and use steel plates or rubber gaskets to level uneven areas. It is forbidden to use easily compressible materials (such as wooden boards).

Anti-settling treatment

The ground needs to be compacted in areas with soft soil, and piles or foundation thickness should be increased if necessary.

Regularly check whether the foundation is cracked or settled (especially in the rainy season or after freeze-thaw).

Key details

Inlet and outlet connection

The interface uses flange or threaded connection, and a flexible joint (such as a rubber hose) is installed between the pipe to reduce vibration transmission.

The flange gasket is made of corrosion-resistant EPDM, and the bolts are tightened evenly diagonally to avoid unilateral force.

Manhole and inspection port

The manhole diameter is ≥500mm and is located close to the top of the water tank for easy internal cleaning and maintenance.

The manhole cover needs to be tightly sealed, and waterproof strips are installed on the edge to prevent rainwater from seeping in.

Overflow pipe and drain pipe

The overflow pipe diameter is ≥1.5 times that of the water inlet pipe, and the height is slightly lower than the top of the water tank to prevent the water level from being too high.

The drain pipe is located at the lowest point at the bottom of the water tank, and sediment is discharged regularly (recommended once a quarter).

Antifreeze and insulation

In cold areas, the outer wall of the water tank is wrapped with insulation material (polyurethane foam steel plate or rubber foam aluminum foil plate), with a thickness of ≥50mm.

If necessary, install electric heating tape at the bottom or pipe to prevent ice expansion from damaging the tank.

Anti-corrosion measures

The embedded parts of the foundation (such as anchor bolts) need to be hot-dip galvanized or coated with epoxy anti-rust paint to avoid rust affecting stability.

Anti-ultraviolet coating (such as polyurethane topcoat) is added to the outer surface of the water tank in coastal or chemical areas to delay resin aging.

Common problems and solutions

The foundation settlement causes the water tank to tilt

Handling: Suspend use, empty the water tank and re-level the foundation. Severe settlement requires reinforcement of the foundation.

Leakage at flange connection

Handling: Replace the sealing gasket, clean the flange surface, and tighten the bolts evenly (tighten them in diagonal order in batches).

Bottom ice in winter

Prevention: Install an insulation layer, keep the water tank full (water is denser than ice, delaying freezing), or set up a circulating water pump.

Rust on the foundation surface

Maintenance: Regularly remove the rust layer, apply anti-rust paint, and re-galvanize the steel bracket every 3 to 5 years.

Summary

The basic design and detail treatment of the water tank are the core to ensure its long-term stable operation:

Foundation: It must meet the requirements of load-bearing, horizontality and anti-settling, and the material selection should be adapted to local conditions.

Details: Sealing, anti-corrosion, and insulation measures are in place, and regular inspection and maintenance can avoid 80% of the risk of water leakage.

Tip: Before installation, the load must be verified by professionals. Customized reinforcement plans are required for complex environments (such as seismic zones and high-corrosion areas).