Pore Size Distribution of Nonwoven Geotextiles
The applicability of the mercury intrusion technique to determine the pore size distribution (PSD) of geotextiles was evaluated. The method was found to be simple and rapid, and an ASTM standard for soils and rocks already exists (ASTM Test Method for Determination of the Pore Volume and Pore Volume Distribution of Soil and Rock by Mercury Intrusion Porosimetry [D 4404]). The PSD determined from the mercury intrusion technique on nonwoven geotextiles was compared to that obtained from the Image Analyser, and the results are in good agreement. It was also found that the PSD of compressed fabrics, the case in most field installations, can be obtained by testing the specimen compressed to a known thickness between two perforated plates. Finally, the permeability of the fabric was predicted from PSD data, and the values agreed very well with those obtained experimentally.