Leakage through a geomembrane having defects

Abstract

A method of preventing leakage through the bottom of a large reservoir by adapting a geomembrane placed on the bottom. A large-scale permeability test was performed before designing this method, and the report of this test was given at the 3rd International Conference on Geotextiles. Geotextiles, which were placed under the geomembrane, were compressed by water pressure and became impermeable. Water, through defects in the geomembrane, did not flow horizontally through the geotextile which was deemed permeable. As a result of the test the following was proved: that geotextiles helped close the contact between the geomembrane and the rough ground surface, and prevented flow through cavities caused by the rough ground surface. The geotextiles had the double advantage of having a cushioning effect and preventing horizontal flow under the geomembrane. The research work was performed to investigate the leakage phenomena through the geomembrane having defects.