WX-2000 Soil Free Expansion Rate Tester Expansion Rate Tester Free Expansion Rate Tester

1. Take representative air dried soil samples and grind them all through a 0.5mm sieve. After mixing evenly, take about 50g and place it in a soil container. Transfer it to an oven and bake it at a temperature of 105~ll0 ℃ until constant temperature is reached. Take it out and cool it in a dryer to room temperature. 2. Install the neckless funnel on the bracket, align the lower mouth of the funnel with the center of the measuring cup, and maintain a distance of 10mm from the cup mouth. 3. Take out the soil sample from the coal dryer, pour it into the cup with a spoon, fill it up, and scrape the soil surface along the cup mouth. Then, pour the soil sample from the measuring cup into the spoon, and place the measuring cup in the center of the lower mouth of the funnel as shown in the figure. Pour the soil sample in the spoon once and then remove the funnel. Use a flat blade to gently scrape off excess soil sample perpendicular to the cup mouth (strictly prevent vibration), and record the mass of soil in the cup. 4. According to the provisions of Regulation 3, the second sample shall be weighed for parallel measurement, and the difference in mass between the two measurements shall not exceed 0.1g. 5. Place the cylinder on the test bench, inject 30mL of distilled water, and add 5mL of 5% analytical pure sodium chloride solution. Then pour the soil sample from the soil cup into the measuring flask. 6. Stir the suspension inside the measuring cylinder with a stirrer. The stirrer should go up to the liquid level and down to the bottom, stirring 10 times (about 10 seconds). Take out the stirrer, rinse the upper particles attached to the stirrer into the measuring cylinder, and rinse the inner wall of the measuring cylinder to make the liquid level inside the measuring cylinder reach about 50ml. At the scale. 7. After the soil sample is deposited in the measuring cylinder, the sample volume is recorded approximately every 5 hours, and the estimated volume is 0.1 mL. When reading, it is required that the line of sight is on the same plane as the soil surface. If the soil surface is inclined, take the average value of the high and low readings. When the difference between two readings is not greater than 0.2 mL, it is considered stable expansion. Use this stable reading to calculate the Free expansion rate. 8. Calculate the Free expansion rate of soil sample according to the following formula: FS=V-V0/V0 X 100, where: FS - Free expansion rate,%, calculated to 1%; V - Volume of soil sample after expansion and stabilization in a measuring cylinder, mL; VO - Volume of measuring soil cup, mL, which is the free accumulation volume of dry soil. 9. Immediately wipe clean after use and place in a dry place.

• 1. It is applicable to the Free expansion rate of clay. The Free expansion rate is the ratio of the difference between the volume of loose dried soil adhering to water and the volume of free accumulation in air, which is indicated by percentage to determine the expansion characteristics of unstructured loose soil adhering to water
• 2. The main structure of the soil expansion rate measuring instrument is composed of: 1. a diameter funnel with an upper mouth diameter of 60mm and a lower mouth diameter of 5mm; 2. a soil measuring cup with an inner diameter of approximately 20mm; Volume is about 10ml 3. Mixer with disc: diameter 18mm