Authors : Venugopalan K V

Volume/Issue : Volume 8 - 2023, Issue 12 - December

Google Scholar : http://tinyurl.com/3d45875b

Scribd : http://tinyurl.com/3e6n7cfc

DOI : https://doi.org/10.5281/zenodo.10453305

Abstract : There are two types of Pavements, namely flexible Pavement and Rigid Pavement. Flexible pavements are constructed with Bituminous Base Course and wearing Coat over the Granular Subbase/ Base course. In Flexible Pavement, grain-to-grain contacts transmit the loads to the subgrade soil. Rigid pavements are constructed with Cement Concrete slabs constructed over a Granular Sub Base (GSB) layer or a levelling course of Dry Lean Concrete (DLC) layer. In Rigid pavement traffic loads are transmitted to the subgrade through the bending action of the concrete slab and hence while designing concrete pavements, the flexural strength of concrete (modulus of rupture) is used rather than its compressive strength, as concrete fails in flexure rather than compression. In hot climatic regions like India, where heavy truck loads contribute to the deterioration of Bituminous wearing surface resulting in degradation of riding quality, an effective solution is required to rehabilitate the damaged pavement. One such approach involves overlaying the damaged pavement with a fresh Bituminous layer to enhance its strength and rehabilitate the surface. However, rutting of the Bituminous layer remains a common issue, especially in tropical areas like India with significant truck traffic. Adopting Plain Cement Concrete (PCC) Overlay with White Topping technology has proven beneficial to address this problem. This innovative technique offers improved structural strength, enhanced durability, cost- effectiveness, reduced maintenance expenses and a lower life cycle cost in comparison to traditional Bituminous surface overlays. The White Topping technology encompasses various classes, including Conventional White Topping, Thin White Topping (TWT) and Ultra-Thin White Topping (UTWT), each characterized by the thickness of the white topping layer applied over the existing Bituminous surface. This technical paper broadly explains the advantages and disadvantages of White Topping Technology and the Life Cycle Cost comparison between Bituminous overlay, Thin White Topping and Ultra-Thin White Topping overlay to establish the relative cost savings of Thin White Topping Overlays.