ABSTRACT
Abstract The reinforcement of bituminous pavements is quite widespread especially under severe loading conditions. Designers tend to use a wide range of synthetic interlayers, not always in consideration of their technical properties. Applications vary from nonwoven low-modulus geotextiles to high strength polyester geogrids. In the paper we describe the results so far obtained in an experimental investigation carried out by our Department laboratories in co-operation with TENAX S.pA. After a preliminary study, based upon static tests, which allowed to acknowledge the ductility increase obtained with some synthetic interlayers, a series of dynamic tests was planned. Fullscale square samples of bituminous mixes, some of which containing different geosynthetics, were dynamically loaded up to failure with the aim of improving the understanding of samples behaviour. During the tests, at intermediate stages, static tests were carried out. Experimentation is not complete yet; however here the first results regarding cracking reflection are presented. Failure cracking patterns, that are very different in the case of overlays standing upon pre-fissured bases, demonstrate the benefits of enclosing geosynthetics in pavements. Keywords: Dynamic tests, fatigue, flexible pavements, geosynthetics, interlayers, macroreinforcement.
