Eric Blond discusses how poor groundwater management is a primary cause of failure of geotechnical structures, such as retaining walls, roadways, embankments and dams. Such structures must be designed to control water and avoid loss of bearing capacity as well as to prevent internal erosion. Granular materials with a sufficient permeability have historically been used for that purpose, however, these are scarce in several regions of the world. Geotextile filters offer an excellent alternative because of their ease of transport and use. However, their ability to perform as a filter must be verified, as would be the case with a granular filtration material.

In this webinar, ISO 18228-3 Design Standard will be introduced as the current state of the art for designing geotextile. The strategy used to verify the compatibility of a geotextile with a soil to prevent blinding, clogging and piping will be described, based on soil mineralogy, gradation and permeability, as well as geotextile properties such as opening size, permeability, number of constrictions and Percent Open Area. Other failure mechanisms such as chemical or biological clogging will also be discussed.