Experimental Study on Practice of Cement Treated Subbase (CTSB) Layer in Flexible Pavement of National Highways in India

Abstract. Due to the large number of infrastructure projects taking place in rural and urban areas there has been a shortage of building materials. The road industry is looking at ways to improve low-quality materials that are easily accessible for use in road construction. Cement / lime treatment has become an acceptable way to increase soil strength and consistency with moderate proportions, to reduce the number of compounds. The Indian roads congress (IRC) has developed a special edition for the mixed construction of the base / ground floor. There is no design guide currently available for the under the cement base. To overcome this problem, the aim of the current project is to create a chart of the paved area using concrete and limestone on rural and urban roads with small and medium vehicles. It not only saves money but also helps to increase the life cycle of roads. At the base of the road, there are different soils or granite materials available for construction, but they may indicate insufficient structures and lead to significant road stress and reduced life. However, the addition of a stabilizing agent such as cement, asphalt, lime or other non-traditional materials can improve soil properties. Among these various stable materials, cemented materials improve strength and high strength, and demonstrate the excellent performance of the paved system and high durability. Solid foundations can provide inexpensive solutions to many common designs and building conditions. Cement Treated Sub Base (CTSB) is a common method used on road foundations to improve its engineering properties due to the durability of cement where moisture is present and extends the healing time. The bonded base material provides additional strength and support without increasing the overall thickness of the mortar layers. Depending on the needs of the project, CTB increases construction speed, improves the capacity of the pavement structure, or in some cases reduces the full-time project. In addition, a strong foundation reduces deviation due to heavy traffic loads, thereby extending the life of the pavement. CTB base thickness is reduced due to higher carrying capacity compared to granular base thickness.