Performance Studies on white topping layers over flexible pavement
S Rashmi, K. Rajesh Kumar, Basavaraj Akki, I. Rajasri Reddy
Abstract
Abstract The main focus of the present era is to construct a long-lasting and better performing pavement. Usually, with respect to the rehabilitation of the pavement, the construction agencies go with the bituminous overlays as their first priority without considering the condition of the existing pavement structure. But CC pavements have proved that they perform better and are long-lasting as new pavement as well as when used for rehabilitation of the existing pavement. And hence it is the era where the Thin and Ultra-Thin White Topping methods are gaining their popularity. Hence in this study, in order to arrive at the performance of the TWT and UTWT methods, various types of basic and the performance tests have been carried out with different combinations of concrete i). Plain Cement Concrete ii). Cement replaced by Ground Granulated Blast furnace Slag (GGBS) (50%) iii). With admixture (Conplast NC) iv) 50% Ground Granulated Blast Furnace Slag GGBS + Conplast NC. Later to understand the performance of these combinations, the composite beams with varying thickness are subjected to repeated wheel loads under Modified Immersion Wheel Tracking Equipment along with a bituminous layer of 50mm thick below the cement concrete layer. The performance results of 150mm thick admixture added CC beam and the 100mm thick GGBS & Admixture added CC beam has almost the same value. Hence, it can be concluded that the slab thickness can be reduced by 50mm by replacing 50% GGBS to the Admixture added CC beam.