BLINDING AND CLOGGING OF A NONWOVEN GEOTEXTILE

摘要

The filtration compatibility of soil-geotextile systems has been assessed experimentally in the laboratory with the gradient-ratio test. A nonwoven geotextile was used against a variety of model soils that were prepared from glass beads. They exhibited a range of fines content, in both gap-graded and broadly -graded size distributions. Filter blind- ing and clogging, if it happens, occurs within hours of initiating unidirectional flow. The zone of soil above the geotex- tile that is influenced is relatively thin. In gap-graded soils, the movement of fine particles appears to occur at a condi- tion of D_85/D_15>8. A new dimensionless index is proposed to quantify the internal stability of gap-graded soils.