This coarse-grained soil constant head permeameter is based on Darcy's law.It calculates the permeability coefficient of a soil sample by measuring the seepage flow and head loss under constant head conditions.

Coarse-grained soil constant head permeameter

Model:TGSYQ-1

I.Product Introduction

The coarse-grained soil permeability tester was developed based on the"TB10751-2018 Standard for Acceptance of Construction Quality of High-SpeedRailway Subgrade Engineering".It is used for constant head permeability testing of coarse-grained soils and is suitable for determining the permeability coefficient of coarse-grained soils and graded crushed stone with a particle size not exceeding 75 mm.The instrument consists of a metal tank,a water supply system,a pressure measurement system,and a data acquisition system,and is designed and manufactured with reference to relevant standards such as ISO 17892-11:2019,EN ISO 17892-11:2019/BS EN ISO 17892-11,and ASTM D2434.

The metal tank is made of high-strength material,with an inner diameter of 300mm,a height of 500mm,and a wall thickness of 10mm,capable of withstanding various mechanical forces during testing.The water supply system includes an 80L water tank to ensure the stability of the water head during testing.The pressure measurement system is equipped with 5 pressure test tube,which can accurately measure changes in water head height at different locations.

II.Working Principle and Test Method

The new standard coarse-grained soil constant head permeameter is based on Darcy's law.It calculates the permeability coefficient of a soil sample by measuring the seepage flow and head loss under constant head conditions.

Its working principle can be summarized as follows:the seepage flow rate and the head height at different points are measured in the test device,thereby calculating the seepage velocity and hydraulic gradient,and then substituting them into the formula to calculate the permeability coefficient.

III.Technical Parameters

Metal barrel inner diameter:300mm

Metal bucket height:500mm

Metal barrel wall thickness:10mm

Water tank capacity:80L

Number of pressure testing tubes:5

Pressure testing tube inner diameter:6mm

Pressure test hole spacing:50mm

Test pressure tube scale interval:1 mm

Seepage water pipe diameter:16mm

Overflow pipe diameter:16mm

Permeable plate aperture:3.5mm