Unformatted text preview: rection. Hydrometer Test 1. Take the beaker containing the soil and dispersing agent, gentle stir with spatula to loosen up particles, then transfer to the dispersion cup, ensuring beaker and spatula have been thoroughly 2. Place dispersion cup containing soil slurry on to the stirring apparatus. Ensure cup has been “hooked” on properly. Run for aprox. 1 minute. 3. At the end of the stirring period, “unhook” cup, rinse down mixing shaft then completely remove cup from stirring apparatus. 4. Pour the soil slurry into a hydrometer glass cylinder, rinsing down the inside of the cup while pouring, ensuring not to lose any material! Add distilled water within a centimetre of the mark. 5. Cover the open end of the cylinder with a stopper and secure it with the palm of your hand. Then turn the cylinder upside down and back upright for a period of one minute. (The cylinder should be inverted approximately 60 times during the minute.) 6. Set the cylinder down and record the time. Remove the stopper from the cylinder. After an elapsed time of one minute and forty seconds, very slowly and carefully insert the hydrometer for the first reading. (Note: It should take about ten seconds to insert or remove the hydrometer to minimize any disturbance. The release of the hydrometer should be made as close to the reading depth as possible to avoid excessive bobbing). 7. The reading is taken by observing the top of the meniscus formed by the suspension and the hydrometer stem. The hydrometer is removed slowly and Winter 2013 7 CIVE 153 – Earth Engineering Hydrometer Analysis Department of
Engineering placed back into the control cylinder. Very gently spin it in control cylinder to remove any particles that may have adhered. 8. Take hydrometer readings after elapsed time of 2 and 5, 8, 15, 30, 60, 250 minutes and 24 hours RESULTS Hydrometer Analysis: 1. Calculate the percent retained and the percent passing for the Sieve Analysis – Coarse Material (Table 2), and Fine Material (Table 3). *refer to sieve analysis...
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- Winter '13
- Civil Engineering, hydrometer, hydrometer analysis, Earth Engineering