ASTM D1557
Full Name
ASTM D1557 – Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Modified Effort (56,000 ft-lbf/ft3 (2,700 kN-m/m3))
Scope
ASTM D1557 is a standard test method used to determine the maximum dry unit weight and optimum moisture content of a soil. This information is crucial for designing compacted soil fills, such as embankments, dams, and road bases.
Test procedure:
- Sample preparation: a representative soil sample is obtained and prepared by passing it through a specified sieve size to remove coarse particles.
- Moisture content determination: the natural moisture content of the soil is measured.
- Compaction: the soil sample is placed in a cylindrical mold and compacted using a mechanical tamper in a series of lifts. The number of blows per lift and the total number of lifts are specified in the standard.
- Weight and moisture content measurement: the compacted soil sample is weighed, and its moisture content is determined.
- Calculations: the dry unit weight of the soil is calculated by dividing the weight of the dry soil by the volume of the mold. This process is repeated for soil samples with varying moisture contents.
- Plotting: the dry unit weights are plotted against their corresponding moisture contents to create a compaction curve.
- Determination of maximum dry unit weight and optimum moisture content: the maximum dry unit weight is the highest point on the compaction curve, and the optimum moisture content is the moisture content at which the maximum dry unit weight occurs.
ASTM D1557 testing is essential for ensuring the stability and performance of compacted soil structures. By determining the maximum dry unit weight and optimum moisture content, engineers can specify appropriate compaction requirements during construction to achieve the desired density and stability.
ASTM D1557 Accredited Laboratory
Applied Testing & Geosciences, LLC is accredited for performing tests using the ASTM D1557 standard.
Contact us today to learn more about our testing capabilities and how we can support your business.
Resources
Keywords
compaction; soil; laboratory; modified effort; test method; dry density; optimum moisture content; standard proctor; compaction curve; maximum dry density; moisture-density relationship; compaction energy; proctor test; density; moisture content