Soil hydrometer apparatus, often used in conjunction with a sedimentation cylinder, are primarily used to determine the particle size distribution of fine-grained soil, specifically silt and clay fractions.They measure the specific gravity of soil samples in suspension, which allows for the calculation of the percentage of different sized particles. This information is crucial for understanding soil properties and behavior.
Here’s a more detailed breakdown:
Purpose:
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Particle Size Distribution:Hydrometer analysis helps determine the percentage of sand, silt, and clay particles within a soil sample.
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Fine-Grained Soil Analysis:It’s particularly useful for analyzing the finer fractions of soil (silt and clay), which are often not accurately determined by sieve analysis alone.
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Predicting Soil Behavior:The particle size distribution, obtained through hydrometer analysis, can be used to predict various soil properties, including its suitability for different engineering applications or its water-holding capacity.
How it works:
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Sedimentation:The hydrometer measures the settling rate of particles in a water suspension.
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Stokes’ Law:The method relies on Stokes’ Law, which describes the relationship between particle size and its settling velocity in a fluid.
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Hydrometer Readings:Readings taken over time allow for the calculation of the percentage of different particle sizes present in the soil sample.
Key Features:
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Specific Gravity Measurement:Hydrometers are calibrated to measure the specific gravity (or density) of liquids, which is the ratio of the liquid’s density to the density of water.
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ASTM Standards:Soil hydrometers are typically manufactured according to the specifications of the American Society for Testing and Materials (ASTM).
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Accuracy:Hydrometer analysis provides a relatively accurate method for determining the particle size distribution of fine-grained soils, particularly when combined with sieve analysis for a complete gradation curve.
Hydrometer Bath
Hydrometer testing sedimentation testing viscosity testing any other application where visibility of product is required. Suitable industries: Soil testing laboratories, petroleum testing laboratories and water research laboratories.
Specifications:
- Powder coated grey electro-galvanised outer case with a brushed finish stainless steel interior which is acid resistant
- Temperature range: Digital Controller – 5C above ambient to 99.9C, accuracy +-0.1C sensor PT100, for below ambient temperatures, refrigeration is required
- Controller on stainless steel bridge plate with hole for thermometer
- Nickle plated copper heater
- Robust stainless steel pump unit for forced circulation for temperature stability
- Stainless steel gabled lid available as an optional extra
- 6 Place unit fitted with a 300x250mm toughned glass viewing window for reading of hydrometers
- Dimensions, capacities and weights may vary slightly
Options:
- 6 Place – 160L Unit – Internal: 500 x 250 x 480mm, External: 600 x 300 x 520mm
- 12 Place – 190L Unit – Internal: 750 x 250 x 480mm, External: 850 x 300 x 520mm
- Bouyoucos Cylinders in 1 Mark (SANS)
- Bouyoucos Cylinders in 2 Mark (TMH)
Soil Hydrometer, ASTM 152H,
Ideal for determining the specific gravity of soil, meets ASTM specifications. Each hydrometer is calibrated in a triple accredited ISO/IEC 17025:2005, A2LA accredited laboratory against equipment whose calibration is traceable to NIST. Individually packaged with a multi-language Statement of Accuracy indicating accuracy traceable to NIST.
Bouyoucos Cylinder
- 1 Mark (SANS)
- 2 Mark (TMH)
