Review the guidelines of overlay design for flexible pavements

Abstract

This primary objective of this research is to compare the overlay design guidelines and verify the feasibility of them on Sri Lankan road network. This is focus on overlay design procedures for the flexible pavements. The study included the collection of required traffic and deflection data in several categories of Sri Lankan road network. Deflection data is needed to obtain the remaining structural capacity (Effective Structural Number- SNeff) of the pavement and can be collected through the related departments in Sri Lanka. Sub-grade strength parameters were found using the field and lab CBR (California Bearing Ratio) experiment. The main advantage of this comparison is to identify the most suitable design procedure of required structural overlay thickness according to the several traffic categories of traffic in Sri Lankan road network.