Choosing the Right Permeability Test

Permeability testing is a cornerstone of geotechnical engineering, helping to assess soil behaviour for construction, drainage, and stability. But with multiple testing methods available, how do you know which one is right for your project?

1. Constant Head Method (AS 1289 6.7.1): 
Ideal for highly permeable materials like sands and gravels, with rates between 10⁻² m/s and 10⁻⁵ m/s.

2. Falling Head Permeability (AS 1289 6.7.2): 
Best for well-compacted road construction materials with permeability rates greater than 10⁻⁹ m/s, like DGB20 or well-graded sandy gravels.

3. Flexible Wall Triaxial Permeameter (AS 1289 6.7.3): 
For materials with permeability less than 10⁻⁹ m/s (clays), this method can measure as low as 10⁻¹² m/s.

Get in touch with our Sydney Laboratory today to discuss your project requirements!