Sand Cone Test

1. Objective

The sand cone test determines the in-situ dry density of soil, ensuring it meets compaction requirements.

2. Apparatus Required

• Sand Cone Apparatus
• Calibrated Dry Sand
• Balance
• Metal Tray
• Moisture Content Containers
• Oven
• Scoop and Digging Tools
• Measuring Cylinder

3. Test Procedure

Step 1: Calibration of Sand

The dry density of the calibrated sand is determined using:

γ_s = W_s / V_c

Step 2: Excavation of Soil

A small pit is excavated, and the removed soil is weighed for further analysis.

Step 3: Filling the Hole with Sand

Sand from the cone is used to fill the hole, and its remaining mass is recorded.

Step 4: Calculations

Mass of sand used:

W_h = W_i - W_f - W_c

Volume of excavated hole:

V_h = W_h / γ_s

Bulk density of soil:

γ_b = W_soil / V_h

Moisture content:

w = (W_w / W_d) × 100

Dry density of soil:

γ_d = γ_b / (1 + (w / 100))

Compaction percentage:

Compaction % = (γ_d / γ_d(max)) × 100

4. Acceptance Criteria

If compaction percentage is >95%, the soil is well compacted; otherwise, additional compaction is needed.

5. Advantages & Disadvantages

Advantages

• Accurate and direct in-situ density measurement.
• Simple and cost-effective method.

Disadvantages

• Not suitable for cohesive or high moisture soils.
• Time-consuming compared to nuclear density methods.

6. Conclusion

The Sand Cone Test is a reliable method for determining field density of soil, ensuring adequate compaction.