The Effect of The Bearing Capacity of Sub-Grade Soil on The Thickness and Cost of The Superstructure of Chip Seals

Abstract

Chip seal is an economical flexible pavement type consisting of layers of aggregate and bituminous binders. Chip seal is generally applied for preventative treatment of an existing road or to overlay low-trafficked roads. The thickness of the superstructure of a chip seal is directly related to the bearing capacity of sub-grade soil. The bearing capacity of soil is represented by Resilient Modulus (MR) during the design of the thickness of pavement layers. This study has focused on the effect of the bearing capacity of sub-grade soil on the thickness and cost of the superstructure of chip seals. In addition, two-dimensional numerical modeling was also performed with the thicknesses of the layers found according to the MR. It was indicated that there was a strong correlation between the bearing capacity of subgrade soil and the thickness of the superstructure of chip seals with high R-square values. An increase in the bearing capacity of the sub-grade soil resulted in a decrease in the thickness of the superstructure of the chip seals. Additionally, Plaxis 2D modeling showed that a double-chip seal had less deformation and better bearing capacity compared to a single-chip seal. For this reason, it is economically important to choose the sub-grade soil to be used in the chip seals most properly by also considering the environmental conditions