- The construction of embankment, subgrade, and subbase should be done as per Specifications for Roads.
- A proper camber as applicable to rural roads shall be provided. Drainage layer should be provided in high rainfall areas (annual rainfall exceeding 1000 mm) as laid down in Road Manual.
- Stone/concrete block or Brick on end edge should be laid on either side of the carriageway projecting 50 to 100 mm above the subgrade/subbase for the confinement and protection of cell-filled concrete.
- A hard shoulder with proper cath is necessary for the concrete blocks’ stability since trucks traveling close to the edge may damage the unconfined concrete blocks.
- The width of the hard shoulder should be about 0.85 m on either side of the pavement.
- Formwork of plastic cells shall be laid across the compacted subbase and put under tension with iron spikes so that cells are close to squares in plan.
- Nylon threads passing at 10 mm below the top of the cells shall prevent the cells from collapsing while filling the cells with concrete.
- If any stitch of the cells opens up during tensioning, it should be stapled near the top, middle, and bottom.
- The concrete shall be filled into the cells to a depth of 120 mm, which is about 20 mm higher than the cell’s depth.
- The iron spikes shall be removed after the cells are filled up with concrete. For RCC, two passes of the roller in static mode followed by two passes in vibratory and another pass in static mode shall be sufficient compaction and a good finish.
- The number of passes in static and dynamic modes depends upon the texture of aggregates and moisture content.
- Pan vibrators can be used to compact the conventional concrete having a slump of about 30 to 40 mm.
- The number of roller passes, the amplitude of vibrations, the depth of loose concrete in cells, and the amount of water to be added shall be determined from the trial run.
- The concrete’s surface shall be covered with wet jute mats or paddy straw to prevent drying during hot weather.
