The sand filling method for testing the compaction degree of graded gravel, the steps are as follows.
1. Choose a suitable sand filling tube.
2. Calibrate the quality of the sand in the lower cone of the sand filling tube.
3. Calibrate the unit mass of sand.
4. Choose a flat surface at the test location and clean it.
5. Place the substrate on a clean surface, drill a hole along the center, and put the cut-out material into a plastic bag. After all the materials in this layer are taken out, weigh the total mass.
6. Take a sample from the material, put it into an aluminum box, and measure its moisture content.
7. Place the base plate on the test pit, place the sand filling tube in the center of the base plate (the quality of the sand in the tube is known), turn on the switch, and let the sand flow into the test pit. When the flow stops, turn off the switch. , carefully remove the sand filling cylinder and weigh the remaining sand.
8. Calculate the degree of compaction.