Structural Adequacy of Flexible Pavements with Types and Widths of Shoulders

Abstract

Very little information is available on the role of the shoulders in respect to load carrying capacity and the performance of a flexible pavement. The present study aims at determining the effect of different types and widths of shoulders on the structural capacity of a flexible pavement. Plate load tests were conducted on the pavement model sections using 300 mm diameter plate to estimate the load carrying capacity as well as the pressure distribution in the pavement. The test results indicate that the load carrying capacity of a pavement increases with the quality of the material used in the construction of the shoulder. It increases with the width of the shoulder also. It is found that the load carrying capacity of a pavement with a gravel shoulder is 33% more as compared to that of a pavement with earthen shoulders. Results also indicate that the lateral confinement provided by the gravel shoulder is higher. The pressure distribution in the pavement as well as in the shoulder improves with better quality of shoulder and it is 31% more in a pavement with a gravel shoulder as compared to that in a pavement with an earthen shoulder.