"Quality Acceptance Standard for High-speed Railway Subgrade Engineering"
TB 10751-2018 (Summary of Appendix)
Appendix C. Coarse-grained soil penetration test method
C.0.1 This penetration test method is used to determine the coarse-grained soil and graded gravel with a maximum particle size not greater than 75mm
Permeability coefficient k. For coarse-grained soil with a maximum particle size not exceeding 10 mm, the "Railway Engineering Geotechnical Test Regulations" may be used
(TB 10102) The constant water head method is used to determine the permeability coefficient k.
C.0.2 The test water should be clean and natural water, and the degassing should be performed by using the air extraction method or boiling method before the test. test
During the inspection, the water temperature should be 3 ℃ ~ 4 ℃ higher than the room temperature.
C.0.3 The equipment used in this test shall meet the following requirements:
1 Normal water head permeameter device:
The inner diameter of the bottom metal cylinder is 300mm, the height is 500mm, and the wall thickness should not be less than 10mm; inside the glass manometer
The diameter should be 6mm, and the division value is 1mm; there are five pressure measuring holes, numbered from top to bottom as 1 #, 2 #,
3 #, 4 #, 5 #, the distance between the pressure measuring holes is 50mm; the diameter of the seepage hole should not be less than 15mm; inside the overflow pipe
The diameter should not be less than 15mm; the permeable plate is divided into an upper permeable plate and a lower permeable plate, the aperture of the permeable plate should be selected
3mm ~ 5mm. The adjustment tube and the overflow pipe should adopt the rubber tube matched with the seepage hole and the overflow hole.
2 Bench scale: Weigh 30kg and the division value is 1.0g.
3 Measuring cylinder: volume 1000ml.
4 Thermometer: The division value is 0.5 ℃.
5 Compacting hammer: mass 9kg ± 100g, diameter 100mm.
6 Other ancillary equipment: stopwatch, steel ruler, rubber tube, adjusting tube, bracket with ruler, bucket
Wait.