Effect of Different Sizes of Crumb Rubber in Asphalt Mixes

Tumi Ori, Kh Singh
Journal of Civil Engineering and Environmental Technology   unpublished
The rapid industrialization, urban development and construction of heavy duty pavements require modification of bitumen. The waste tyre of different sizes with different concentration has been used as modifier. The use of these materials will reduce the cost of bitumen, minimize the environmental pollution and also improve the durability and performance of flexible pavement for future highways construction. The study of the binder include the following testing procedures: penetration, softening
more » ... etration, softening point and ductility test while for the bituminous mixture: Marshall stability test to determine the properties of crumb rubber such as (size and percent of content) which provide the ultimate performance of hot asphalt mix. For this purpose the bitumen modified with 5%, 7%, 9% and 11% by weight of crumb rubber varying its size. Three different sizes of crumb rubber will be used, which are coarse (1.18mm-600µm); medium size (600µm-300µm) and fine (300µm-150µm). On the basis of experimental study the modified bitumen using different sizes and percent of crumb rubber content are analyzed and best size of crumb rubber is suggested.