Statistical-Based Models for Behavior of Flexible Pavements

The main objective of this paper was to provide some useful statistical-based models for flexible pavement behavior. The results of a theoretical analysis, using the finite element (FE) program SAP was utilized in this statistical analysis study. The maximum surface deflection, the maximum horizontal tensile strain (t) at the bottom of AC layer and the maximum compressive strain (c) at the top of subgrade are the most commonly used criteria for flexible pavement design. They were used in this study as the basis for measuring the flexible pavement response. The Statistical Package for Social Sciences (SPSS) version 11.0 was used to relate these parameters to the basic flexible pavement layer properties.
Clearly, the properties of the top layer, asphalt concrete (AC) layer, are the key to control the behavior of flexible pavements. Based on that, the models developed in this paper concerned with the thickness and modulus of AC layer. Three different AC thicknesses and eight different AC moduli were used to investigate the response of flexible pavement. Based on the theoretical and statistical work presented in this study, simple statistical-based models for the response of flexible pavements were developed. These models could be easily used by pavement engineers to predict the flexible pavement indicators; maximum surface deflection, maximum horizontal tensile strain at the bottom of asphalt concrete layer and maximum vertical compressive strain at the top of subgrade layer. The presented models emphasized that the thickness of asphalt concrete layer was the most important independent variable for the response of flexible pavement followed by the modulus of AC layer.