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Test Method

California Test Method (CTM) 220, “Method of Test for Permeability of Soils”

Summary of Test Method

In this test, water is forced, by a falling head pressure, through a soil specimen of known dimensions and the rate of flow is determined. This test is used to determine the drainage characteristics of relatively fine-grained soils and is usually performed on undisturbed samples.

Minimum Sample Size

Undisturbed Sample: 1 Tube (1 lb)
Remolded Sample: 2 Canvas Bags (80 lb)

Last Updated September 29, 2005

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