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[scope of application]

The American standard vertical permeability meter is used for measuring the permeability coefficient (water permeability) of the uncompressed state according to the water permeability under the standard test conditions.

[Related Standards]

ASTMD 4491 Standard test method for determining the water permeability of geotextile by water permeability

[Test Principle]

Volumetric flow rate of water per unit of cross-sectional area per unit of head passing vertically through the geotextile under laminar conditions.