1. Excavation:
Excavation is to be carried out upto a depth approximately 6 to 7 feet from the ground level
Excavated area will be prepared for the installation of new UPVC 8" dia piping using sch-80 ( Dadex, AGM, Steelex) as described below.
2. Preparation of Sand Bed:
Prior to placing the new pipe, the contractor is responsible for preparing a sand bed for proper support and alignment.
Debris from the excavated area will be placed nearest to the excavated area and concreted with a 1:3:6 ratio (cement: sand: aggregate) to create a solid foundation. (Contractor will arrange debris if required).
This concrete bed will serve to safeguard the pipe from bending, ensure proper slope, and maintain the invert level of the pipe for gravity flow.
The contractor must ensure that the sand bed is levelled and stable to support the new drainage system securely.
3. Installation of UPVC Pipe:
After preparation of the concrete bed, the new 8-inch dia UPVC pipe Sch-80 (Dadex , AGM , Steelex) will be installed at a depth of 4 to 7 feet approximately below the existing floor level maintaining the levels for gravity flow of sewerage water.
The new pipe will be connected to each chamber with no leakage as required.
4. Chamber and Manhole Work:
The scope includes the cutting and repair of chambers, using non-shrinkage grout for the repair work.
Any necessary manhole repairs will also be completed, which may include structural patching or reinforcement as per the site requirements.
Cleaning of the chambers will be carried out after the pipe installation to ensure smooth operation.
5. Concrete Floor Repair:
After the installation of the pipe and chamber work, the existing floor will be repaired including compaction, stone soling, 1:3:6 over soling, laying of 1:2:4 concrete mix and finished with a trowel to ensure a smooth, durable surface.
6. Final Completion:
All work will be carried out in full accordance with the direction of the school management and will adhere to the highest standards of safety, quality, and functionality.
The contractor is fully responsible for ensuring that all aspects of the work, including excavation, concrete bed preparation, pipe installation and manholes repairs, carried out as per specification and completion within the required timelines.