How to Calculate Crushed Stone Volume for Foundations

Correct calculation of material quantities is the key to successful construction. An error can lead to work stoppages or unnecessary expenses.

Calculation Formula

To calculate the volume of crushed stone, use the classic formula:

V = L × W × H × K

Where:

• L — area length (m)
• W — area width (m)
• H — crushed stone layer thickness (m)
• K — compaction coefficient (1.15-1.3)

Calculation Example

Let's say we need a cushion under a 10×8 meter foundation, with a layer thickness of 20 cm.

V = 10 × 8 × 0.2 × 1.2 = 19.2 m³

Accounting for compaction, approximately 20 cubic meters of crushed stone will be needed.

Converting to Tons

The average bulk density of granite crushed stone is 1.4-1.5 t/m³.

For our example: 20 × 1.45 = 29 tons.

Tip: always order crushed stone with a 5-10% buffer. This eliminates the need for reordering.

Conclusion

Accurate calculations save money and time. Use the formula and don't forget the compaction coefficient.