Structural Design for GRP Water Tank

I need a complete structural design for a cylindrical GRP underground water tank.

Specifications:
- Diameter: 3.0 m
- Length: 12.7 m
- Cover: 20 cm backfilling above tank
- Support: Raft foundation below tank
- Water table level: same as ground level

Design Requirements:
- Required GRP wall thickness
- Raft foundation thickness below the tank
- Consideration of loads and conditions:
- Internal water load
- External soil pressure
- Groundwater pressure (water table at ground level)
- Surcharge load and backfilling above tank

Software:
- Design model using ETABS

Deliverables:
- Design models
- Calculation report (PDF)
- Drawings/sections showing tank, raft, and reinforcement

Standards: ACI or equivalent international standards compliance.