Test Method Title
Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Modified Effort
Reference Number
ASTM D1557
Material
Soil
Test Property
Maximum dry density, optimum moisture content
Description of Test
A soil at a selected water content is placed in five layers into a mold of given dimensions, with each layer compacted by 25 or 56 blows of a 10-lbf (44.5-N) rammer dropped from a distance of 18-in. (457-mm), subjecting the solid to a total compactive effort of about 56,000 ft - lbf/ft3 (2700kN-m/m3). The resulting dry unit weight is determined. The procedure is repeated for a sufficient number of water contents to establish a relationship between the dry unit weight and the water content for the soil. This data, when plotted, represent a curvilinear relationship known as the compaction curve. The values of optimum water content and modified maximum dry unit weight are determined from the compaction curve.
Number of Test Specimens
5
Test Specimen Size
2300 - 5600 grams
Keywords
compaction, Density, modified effort, modified proctor test, moisture-density curves, Proctor, soil compaction