Bubblepoint Testing of Geotextiles: Apparatus and Operation

A simple, inexpensive device for measuring geotextile pore sizes, using ASTM D 6767, is described and its operation is outlined with guidance for correct operation. The accuracy and consistency of the test are shown. The test appears to have better consistency than the apparent opening size (AOS) test, avoids the inherent and operator-dependent problems of theAOS test, and further, describes the entire pore size distribution of a geotextile, making it useful for developing a more complete filter criterion. Suggestions are made for improving ASTM D 6767.