An Empirical Approach to Filtration Criteria for Non-Woven Geotextiles
SourceMany filter design criteria have been produced by various researchers. However, none of these criteria have been universally accepted to be the standard design method. In order to develop a reliable design criteria, an empirical design method was produced. The methodology adopted for this study consisted of the filtration test (long-term gradient ratio test), the hydrodynamic sieving test, and the image analysis test. In the filtration test, eight different soil gradings were tested with six sizes of non-woven needled-punched geotextiles to determine the compatibility of each soil/geotextile combination system. From the hydrodynamic sieving test and the image analysis test, the opening size distribution (OSD) was determined, including the influencing factor of a geotextile's compressibility. As soil characteristics can be determined from standard soil tests and knowing the geotextile's characteristics (OSD) together with the soil/geotextile compatibility, an empirical design method could be developed.