- 2080 Bhadra · 6 marks
Rate analysis: M20 PCC, raft foundation
Short answer
For nominal mix 1:1.5:3, dry volume factor 1.54. Per m3: cement 8.06 bags, sand 0.42 m3, aggregate 0.84 m3, skilled 1 md, unskilled 7 md. Rate = Rs 21,900.60 per m3; raft cost = Rs 2,190,060.
Prepare the rate analysis for M20 PCC work in 10 m × 10 m × 1 m raft foundation.
Basis
Raft = 10 x 10 x 1 = 100 m³ of M20 concrete (nominal mix 1:1.5:3, IS 456 Table 9). Dry volume = 1.54 x wet volume. Rates are illustrative; mixing is manual (a concrete mixer would be preferred for this volume and would reduce the labour).
Quantities per m³
- Cement = 1.54/5.5 = 0.2800 m³ = 8.06 bags
- Sand = 1.54 x 1.5/5.5 = 0.4200 m³
- Aggregate = 1.54 x 3/5.5 = 0.8400 m³
Rate analysis (per m³)
| Description | Qty | Unit | Rate (Rs) | Amount (Rs) |
|---|---|---|---|---|
| Cement (0.2800 m³) | 8.06 | bag | 900.00 | 7,254.00 |
| Sand (0.420 m³) | 0.42 | m³ | 2,500.00 | 1,050.00 |
| Aggregate 20 mm (0.840 m³) | 0.84 | m³ | 3,500.00 | 2,940.00 |
| Mason (skilled) | 1 | md | 1,200.00 | 1,200.00 |
| Labour (unskilled) | 7 | md | 900.00 | 6,300.00 |
| Water, curing, tools (L.S.) | 1 | L.S. | 300.00 | 300.00 |
| Sub-total | 19,044.00 | |||
| Contractor's overhead and profit | 15% | 2,856.60 | ||
| Rate per m³ | 21,900.60 |
Quantities and cost for the raft (100 m³)
- Cement = 806.4 bags; sand = 42.0 m³; aggregate = 84.0 m³
- Skilled labour = 100 md; unskilled = 700 md
- Cost = 100 x 21,900.60 = Rs 2,190,060.00
Answer: Rate of M20 PCC = Rs 21,900.60 per m³; cost of the 100 m³ raft concrete = Rs 2,190,060.00 (excluding formwork, reinforcement and VAT).
✓ Answer checked by Claude Opus 5.5 (high effort)
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