1、 Application and Instructions for Penetrometer
This instrument can be used to measure the permeability test of clayey soil under variable water head.

2、 Structural performance of permeameter
The instrument mainly consists of an upper cover, a base, a sleeve, a ring knife, a permeable stone, a screw, etc. This instrument does not come with a water supply device.

3、 Main specifications of permeameter
Sample size: 61.8mm x 40mm (30 square centimeters)
Instrument dimensions: 182x172x190mm (LxWxH)

4、 Operation steps of permeameter
1. Refer to the Geotechnical Test Code SD128-012-84 of the Ministry of Water and Electricity for sample preparation, or refer to JTJ051-93 "Highway Geotechnical Test Code" T013-93
2. Place the permeable stone and sealing ring into the base, apply a layer of Vaseline to the inner wall of the sleeve, put in the soil sample ring knife, scrape off excess Vaseline and place it on the base.
3. Place the sealing ring, permeable stone, upper cover, tighten the screw, and ensure no water or air leakage.
4. Connect the inlet pipe to the water supply device, and use a water exhaust to level the instrument,
5. Under the action of a water head not exceeding 200cm, let it stand for a certain period of time, and start measuring after water escapes from the outlet pipe.
6. During the experiment, flush the water head pipe to the desired height, then close the pipe clamp and start the stopwatch. At the same time, measure the starting water head h1, and after time t has passed, measure the termination. The water temperature at the time of the experiment and termination is also measured,
7. Calculate the permeability coefficient (variable head) according to the formula;
KT=2.3log
In the formula: a - cross-sectional area of variable head pipe, square centimeters
L - Penetration diameter, equal to the height of the sample. cm
H1- Initial water head, centimeters
H2- Water head at termination, centimeters

5、 Precautions for Penetrometer:
1. The rubber pipe at the outlet of the upper cover should not be easily fitted to the root, and a minimum of 6mm should be left to prevent compression with the sleeve,
2. After each use, it should be wiped clean and dried, and the sealing ring should be coated with talcum powder for storage.
3. The soil cutting ring knife should be properly stored to prevent damage to the cutting edge.