Development and evaluation of Sulphur modified bitumen binder

Abstract

The performance of a bituminous pavement mainly depends on the properties of binder used, volumetric properties of bituminous mixtures and external factors such as environment and traffic volume. The higher traffic volume producing higher stresses and temperature variations affecting the binder performance are the main causes for pavement distresses in the form of fatigue cracking and permanent deformation. The solutions to reduce such pavement distresses are mostly in the form of modifying the normal bitumen by using certain additives to give the conventional bitumen better engineering properties and as such are helpful to extend the life span of the bituminous pavement. In this work, an investigation has been made to use commercial sulphur available in local market to modify the conventional bitumen and the modified bir thus developed has been evaluated in the form of its rheological properties. The conventional VG 30 bitumen was used in this work for modification with sulphur at different levels (by weight of the bitumen). The rheological properties of the modified and unmodified binders were studied using a Dynamic Shear Rheometer (DSR). It is observed that the addition of only 2% sulphur with conventional VG 30 bitumen, prepared at 120ͼC temperature results in satisfactory rheological proper ties. Further, as a part of DSR test, it has been possible to study the effects of aging on the rheological properties of unmodified and modified binders. It is observed that the modified binders considered in this study perform much better than the unmodified binders.