Performance of Stone Mastic Asphalt Mix Using Selected Fibres

Abstract

Stone Mastic Asphalt (SMA) is a gap-graded asphalt mixture that depends on the stone-to-stone contact to provide its load carrying capacity against rutting. However, binder draindown is a problem for SMA mixtures, due to its intentional high binder content. This paper details the performance evaluation of two different cellulose fibres used in SMA14 mix; synthetic fibre (Viatop66) and natural fibre (Kenaf) to prevent binder drainage. The cellulose fibres, 0.3 percent by weight of the mixture, were uniformly combined with the dried aggregate before the asphalt cement was added during mixing process. Laboratory specimens were prepared using 50 blows of the Marshall hammer per side. The Optimum Binder Content (OBC) for the SMA14 mix with Viatop66 was found to be 6.1 percent, while the OBC for the SMA14 mix with Kenaf was found to be 5.9 percent. Rut depth obtained for SMA14 mix Kenaf was lower (1.6 mm) compared with SMA14 mix with Viatop66 (1.8 mm). The tensile strength ratio recorded for both mixes are greater than 80 percent, indicating adequate stripping resistance. The fibres were found to interact well with other substances in the SMA14 mix using the Environment Scanning Electron Microscopy (ESEM). This indicates that the natural fibre could efficiently retain the binder in the mix. Therefore, natural fibre (Kenaf) could be an alternative material to replace the synthetic fibre for the SMA14 mixture.

Amazing Types, Properties, and Applications of Fibres in Construction Materials

“…Flax fibres have been used in composite construction materials to improve ductility and as reinforcement for building materials to improve stabilisation [4]. Kenaf is a cellulose fibre that is readily available in tropical and subtropical climates such as Malaysia [20].…”

“…Stone mastic asphalt (SMA) is a common type of mixture [42]. SMA is commonly used as it can improve resistance towards rutting [20]. Rutting is a known issue for asphalt pavements.…”

“…The use of fibres can improve the down drain characteristics of the mixture and even prevent the occurrence of down drain [32,43]. Down drain is when the bitumen of the mixture separates itself from the binder during the mixing process, which lead to many issues [20]. Some problems of asphalt pavements include permanent deformation, rutting, and cracks formed due to fatigue, thermal complications [42,43], ravelling because of oxidation, and binder hardening [40].…”

“…Natural fibres have shown benefits when added to asphalt mixtures. Arshad et al studied two kinds of cellulose fibres in a SMA14 mix, using synthetic fibres and kenaf fibres to stop binder drainage [20]. The results demonstrated that the kenaf fibres performed better in retaining the binder of the SMA14 mix, hence, it can be used as a cheaper and more sustainable substitute to synthetic fibre for this specific mix [20].…”

Use of diatomite and pumice as stabilizers in stone mastic asphalt mixtures

“…Moreover, the toughness of the mixtures is developed with the addition of tire, carpet and polyester fibers when it is compared to the mixtures with cellulose fibers. Arshad, Mansor, Shafie, & Hashim (2016) evaluated the performance of Kenaf (natural fiber) in stone mastic asphalt (SMA) mixtures to examine the drainage of bitumen. Kenaf compared with synthetic fiber (Viatop®66) resulted in a better performance in terms of rut depth.…”