Influence of Bedding Conditions on the Behavior of Geotextile Filters

This paper presents and discusses the results obtained in laboratory tests to evaluate the behavior of filter systems consisting of nonwoven geotextiles overlying different granular materials under confinement. Nonwoven geotextiles with masses per unit area of 200 g/m², 400 g/m² and 600 g/m² were used in the tests. Stainless steel spheres and a coarse aggregate were employed as granular materials underlying the geotextile filter. Specific tests to evaluate the intensity of sagging of the geotextile filter in the voids of the underlying materialwere carried out. Average strains in the geotextile were also obtained in the tests. The grain sizes of the particles that piped through the geotextile filter for different arrangements of spheres as bedding layer for the filter were also assessed. The results obtained showed the influence of the bedding conditions of the geotextile on its deformed shape and retention capacity.