New Concept for the Design of Flexible Pavement at Critical Highway Sections

Document Type : Original Article


1 Egyptian Armed Forces, Egypt.

2 Libyan Armed Forces.


The design procedure of flexible pavement to be completely rational in nature, consideration should be given to all forces acting on pavement through the vehicle's tire. Although the horizontal forces (HF) on the pavements are of significant values, all pavement design methods do not take the actions of these forces on the pavement system into consideration. This may appear to be unrealistic load condition. Previous studies concluded that horizontal forces have significant effect on the response of flexible pavements. The main objective of this research is to recommend/quantify solutions to eliminate the effect of these forces on the response of flexible pavements. To achieve this objective theoretical analysis, using finite element technique, was performed to investigate the response of different flexible pavement sections under various wheel loads. Linear analysis was conducted using the computer program ANSYS 12.1. The basic measuring parameters of flexible pavement in this study were; the maximum surface deflection (SD), the maximum horizontal tensile strain at the bottom of asphalt concrete layer (εt) and the maximum compressive strain at the top of subgrade (εc). A total of 643 cases were studied to investigate the effect of HF on the behavior of asphalt pavements. Based on the response of asphalt pavement under HF, recommended pavement sections were adopted to eliminate the effect of HF. Reduction of the effect of HF on the flexible pavement response may achieved by increasing the AC layer thickness (h1) followed by the asphalt concrete layer modulus (E1) or by increasing the base layer modulus (E2).