AASHTO T180

Full Name

AASHTO T180 – Standard Method of Test for Moisture-Density Relations of Soils Using a 4.54-kg (10-lb) Rammer and a 457-mm (18-in.) Drop

Scope

AASHTO T180 is a standard test method used to determine the relationship between the moisture content and density of soils when compacted under controlled conditions. This relationship, known as the moisture-density curve, is essential for geotechnical engineering applications, particularly in the design and construction of earthworks, embankments, and foundations.

Key aspects of AASHTO T180:

  • Purpose: the primary goal is to find the optimal moisture content (OMC) at which a soil can achieve its maximum dry density (MDD). Compacting soil at OMC ensures the highest level of stability and load-bearing capacity for the intended application.
  • Test procedure: the test involves compacting soil specimens at various moisture contents using a 4.54-kg (10-lb) rammer dropped from a height of 457 mm (18 in.). The resulting dry densities are plotted against the corresponding moisture contents, creating a moisture-density curve.
  • Equipment: AASHTO T180 specifies the use of a standard Proctor mold, rammer, balance, drying oven, and other necessary equipment for conducting the test.
  • Four alternative procedures: the standard offers four alternative procedures based on the soil type and the desired level of compaction:
    1. Method A: uses a 101.60-mm (4-in.) mold for soil passing a 4.75-mm (No. 4) sieve.
    2. Method B: uses a 152.40-mm (6-in.) mold for soil passing a 4.75-mm (No. 4) sieve.
    3. Method C: uses a 101.60-mm (4-in.) mold for soil passing a 19.0-mm (3/4-in.) sieve.
    4. Method D: uses a 152.40-mm (6-in.) mold for soil passing a 19.0-mm (3/4-in.) sieve.

Significance of AASHTO T180:

  • Geotechnical design: the moisture-density relationship obtained from this test is crucial for designing compacted earth fills, embankments, and subgrades for roads, airports, and other structures.
  • Quality control: contractors use this test to verify that the soil compaction on the construction site meets the specified density requirements.
  • Material selection: the test results can be used to evaluate the suitability of different soils for specific applications based on their compaction characteristics.

AASHTO T180 Accredited Laboratory

Applied Testing & Geosciences, LLC is accredited for performing tests using the AASHTO T180 standard.

Our laboratory offers comprehensive soil testing services, including the determination of moisture-density relations according to AASHTO T180. Our experienced technicians utilize calibrated equipment and adhere to strict quality control procedures to provide accurate and reliable results for your geotechnical projects.

Contact us for more information.

Resources

Keywords

moisture content; dry density; compaction; proctor test; standard proctor; optimum moisture content (OMC); maximum dry density (MDD); soil; rammer; mold; geotechnical engineering