A study of geotextile filter usage in the embankment dams
Author(s): Semko Arefpanah, Alireza Sharafi and Fatemeh Salehi
Abstract: Geotextile filtration systems have shown several decades their behavior in dams one of the most important factors in the degradation and eventually, destruction of embankment dams is leakage from different parts therein. In embankment dams under normal conditions, employing grain filters is often proposed as the first option. The first large earth dam using geosynthetic materials was built in 1970 in France. At that time the geotextile acts as a filter on the upstream slope between the rocks and the earth fill and on the downstream slope around the main drains. Since this date, a lot of dams were built using geotextile filters. Also, in the last decades, several studies on the long-term behavior of the used geotextiles were carried out to improve both filtration design rules and products. From this long return of experience, filtration design rules have been improved, and new filtration systems with optimized properties have been developed. As a complement to these filtration systems, a new monitoring solution based on optical fibers has been developed to detect and localize the early signs of malfunctioning, such as leaks or instability, to enhance the long-term performance of the dams. . In the paper, the existing geotextile filter design criteria are shown for the retention criterion and the permeability criterion; the influence of the main factors affecting the filtration design is illustrated and the recent methods to evaluate the internal stability of granular soils are analyzed.