Identification Effect of Nanoclay on Engineering Properties of Asphalt Mixtures

Document Type : Research Article

Authors

Abstract

Nanoclays are new generation of processed clays of interest in a wide range of high performance composites. In other words, nanoclay is defined as a clay that can be modified to make the clay complexes compatible with organic monomers and polymers. Here, it can be said that the polymeric nanocomposites are among the most exciting and promising classes of materials discovered recently. A number of physical properties are enhanced successfully when a polymer is modified with small amount of nanoclay on condition that the clay is dispersed at nanoscopic level. This research has accomplished a comparative rheological test on binders as well as a mechanical test on asphalt mixtures containing unmodified and nanoclay modified bitumen. For that matter, two types of nanoclay were used: Nanofil-15 and Cloisite-15A. While, the rheological test on binder were penetration, softening point, ductility and aging effect, mechanical test on asphalt mixture were marshal stability, indirect tensile strength, resilient modulus, diametric fatigue and dynamic creep test. Test results show that, nanoclay can improve properties like stability, resilient modulus and indirect tensile strength and possess better behavior compared with unmodified bitumen under dynamic creep although it does not seem to have beneficial effect on fatigue behavior in low temperature. Optimum binder content and void in total mixture (VTM) increase by adding nanoclay to bitumen

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