Standard: BS 1377-2, ASTM D4318, AASHTO T89
Liquid Limit Test Set
Liquid Limit Test Set (Casagrande Method) is used to determine the moisture content of soil transitions from plastic state to liquid state under standardized conditions. The apparatus consists of a brass cup, a mechanism for controlling the rate of rotation, a counter, and a grooving tool. During the test, the soil sample is mixed with water to form a paste, and the paste is then placed in the cup. The cup is rotated on a carriage at a standardized rate, and a grooving tool is used to create a groove in the soil paste. The number of blows required for the groove to close over a certain distance determines the liquid limit of the soil.
Available in 2 models:
- Hand operated through the crank.
- Electrically operated at 120 blows per minute based on standard.
Features of Liquid Limit Test Set
- Brass Cup: The cup is made of brass and has standardized dimensions to hold the soil paste during testing.
- Mechanism for Controlling the Rate of Rotation: The cup is attached to a carriage, which is controlled by a motorized mechanism. This mechanism allows the cup to be rotated at a standardized rate during the test.
- Counter: A counter is integrated into the apparatus to keep track of the number of rotations or blows applied during the test. This is essential for accurately determining the liquid limit.
- Grooving Tool: A grooving tool is provided to create a standardized groove in the soil paste. This groove serves as a reference point to observe the soil's behavior as it transitions from plastic to liquid state.
Technical Specifications
| Model Number |
NL 5008 X / 001 |
| Type |
Hand – Operated |
| Product Dimension (mm) |
220 (L) x 168 (W) x 134 (H) |
| Case Dimension (mm) |
215 (L) x 215 (W) x 134 (H) |
| Approx. Weight |
2.5 kg (with case 4.7 kg) |
Unit Consist Of:
| Model Number |
Parts Description |
| NL 5008 X / 002 – P 001 |
Grooving Tool (BS) |
| NL 5008 X / 002 – P 003 |
Grooving Tool (ASTM) |
| NL 5008 X / 002 – P 004 |
Curved Grooving Tool (AASHTO T89) |
| NL 5008 X / 002 – P 002 |
Height Gauge (10mm) |
*1 Copy of Manual Instruction
Standards
- BS 1377-2 is a British Standard that provides guidelines and procedures for conducting laboratory tests to determine the classification and index properties of soils, including particle size distribution, Atterberg limits (including liquid limit), and classification tests.
- ASTM D4318 is an American Society for Testing and Materials (ASTM) standard that focuses on determining the liquid limit, plastic limit, and plasticity index of soils.
- AASHTO T89 is a test method outlined by the American Association of State Highway and Transportation Officials (AASHTO) for determining the moisture-density relations of soils.
Test Procedure of Liquid Limit Test Set
- Sample Preparation: Collect a representative soil sample and remove any large particles or organic materials. Air-dry the sample, crush any lumps and pass it through a sieve with a 0.425 mm opening.
- Setting Up the Apparatus: Set up the liquid limit apparatus, including the cup, grooving tool, and a mechanism to control the rate of moisture addition. Ensure the cup is clean and dry.
- Weighing the Soil: Weigh a specific amount of the prepared soil sample and place it into the cup of the liquid limit apparatus.
- Adjusting Moisture Content: Gradually add water to the soil sample in the cup, mixing it thoroughly. Use a standardized method for moisture addition, such as a drop-counting device.
- Grooving the Soil: After each addition of water, create a groove in the soil using the grooving tool. The groove should be made along the center of the cup.
- Determining Liquid Limit: Continue adding water and grooving the soil until the groove closes for a distance of 13 mm (0.5 inches). The moisture content at this point is the liquid limit.
- Recording Data: Record the number of blows or drops required for the groove to close and the corresponding moisture content. This information is used for calculations.
- Calculating Plasticity Index: If needed, determine the plasticity index by finding the difference between the liquid limit and the plastic limit (determined in a separate test).
- Cleaning the Apparatus: Thoroughly clean the liquid limit apparatus after each test to avoid any residue affecting subsequent measurements.
- Repeat Testing: Conduct multiple tests using different portions of the soil sample to ensure consistency and reliability of results.
