Ultra Thin White Topping: Modern Rehabilitation Technique

Improved and dependable infrastructure, particularly the road network has been given a high priority by the Government. The asphalt pavements have a design period of 5 to 10 years and they require maintenance from time to time. They are susceptible to cracking, rutting, etc. under extreme conditions of weather, daily traffic and loading. Concrete roads have a long life of 30 years or more and do not develop ruts or potholes. They are also not adversely affected by floods and other vagaries of weather. Apart from constructing new roads, it would be in the country’s interest to renew worn out or damaged bitumen pavements, by putting a layer of concrete on top. This is known as WHITETOPPING. The deteriorated bituminous pavements can be rehabilitated using the white topping technology. The type of white topping includes conventional, thin and ultrathin white topping depending upon the thickness of the road. In this paper, we will study about the rehabilitation of existing asphalt pavements using Ultrathin White Topping. It is a 50-100mm thick cement concrete overlay on distressed asphalt pavement. In this project, 3 trial mixes were tested by using IS code and IRC recommendations on the quantity of cement and chemical admixtures to enhance performance and achieve certain economy in construction of pavement. The quality testing of the trial mixes was also carried out. The trial mix giving the optimum results was checked for achieving economy in construction.