Proctor compaction test

The Proctor test establishes the moisture content at which a soil compacts best and the maximum dry density it reaches at that moisture. Compaction specifications for road subgrades, car parks, industrial platforms, engineered fill pads, embankments and dams are all based on these two values.

During the test, the soil is compacted in layers in a standard mould with a fixed compactive effort at several different moisture contents. Dry density is calculated for each point and a density–moisture curve is plotted; its peak gives the maximum dry density and optimum moisture content. Depending on the required effort, the standard or modified (heavy) Proctor method is used — the latter typically for road and airfield pavements.

Once compaction is carried out on site, the in-situ density is measured and the degree of compaction is calculated relative to the laboratory maximum. This gives an objective way to assess the contractor's work and to document that the specified level (for example 95% or 98%) has been achieved.

Tests follow applicable standards (GOST, ASTM D698/D1557 procedures), and results are issued as charts and certificates for projects in Baku and across Azerbaijan.

When you need it

• Road subgrade construction
• Industrial and warehouse platforms
• Engineered fill pads beneath foundations
• Embankments, dams and earth fills
• Control of trench and pit backfilling

What's included

• Sample preparation and removal of oversize particles
• Compaction at several moisture points
• Dry density calculation at each point
• Plotting the density–moisture curve
• Determining maximum dry density and optimum moisture
• Field compaction checks on request

How we work

1. Taking a material sample
2. Laboratory preparation
3. Performing the Proctor test
4. Plotting the curve and calculating results
5. Issue of certificate

Deliverables

• Density–moisture curve
• Maximum dry density and optimum moisture values
• Test certificate
• Field compaction results table on request