This preview shows page 1. Sign up to view the full content.
Unformatted text preview: dispersion cup. 6. Hydrometer ‐ graduated to read in grams per litre of suspension and conforming to requirements for hydrometer 152 H in ASTM Specification E 100. Winter 2013 4 CIVE 153 – Earth Engineering Hydrometer Analysis Department of
Engineering 7. Sedimentation Cylinder ‐ glass, 457 mm in height, 63.5 mm in diameter and marked for 1000 ml volume. 8. Thermometer ‐ accurate to 0.5 °C. 9. Water bath or constant temperature room ‐ to maintain the soil suspension at or near 20°C during the analysis. If a room can be controlled at a constant temperature a water bath is not required. 10. Beaker ‐ 250 ml. 11. Timing device ‐ a watch or clock with a second hand.
12. Distilled Water.
13. Dispersion cup.
14. Misc. items, rubber stopper, spatula, papertowel, etc.
15. Dispersing agent (sodium hexametaphosphate (40 g/L)) PROCEDURE Sample Preparation 1. Use aprox. 250g. sample, sieve over No. 10 (2.00mm) until only aggregate or no particles remain on sieve. 2. Use small splitter, split material passing the No. 10 sieve until there is aprox. 50g sample. Place in beaker, record sample amount on beaker and add 125 mL of the dispersing agent (sodium hexametaphosphate (40 g/L)) solution). Stir the mixture until the soil is thoroughly wet, rinse off spatula. 3. Let the soil soak for a minimum 16hrs. Steps 1 & 2 have been completed for the actual sample you will be testing. Winter 2013 5 CIVE 153 – Earth Engineering Hydrometer Analysis Department of
Engineering Hygroscopic Moisture Content This is preliminary task to determine the hygroscopic moisture correction factor. This is due to possible humidity in the air being absorbed by the dry soil used for the hydrometer test. To attain this moisture correction, follow the proceeding steps: 1. Take a portion of the air dried sample (soil) aprox. 10 to 15g, place in a container (with a known mass), record the soil + container weight, then place into an oven at 110 ± 5°C, dry, and then weigh again (oven dried weight). 2. Ca...
View Full Document
- Winter '13