PAVEMENT STRUCTURAL ANALYSIS CONSIDERING STRESS DEPENDENCY OF LAYER MODULI OF UNCONFINED MATERIALS

It is well known that the function of base layer is to disperse the load acting on the pavement surface and this highly influences durability of the pavement. In pavement analysis, linear multi-layer elastic system is used and it is hereby proposed that k-q nonlinear model be used to represent material properties for base and subgrade layers instead of a linear model. In this research, comparison between linear and nonlinear models for multi-layer elastic subgrade and unconfined base materials is made from the point of view of expected pavement life. Effects of percolation of water into base layer and degree of saturation on the load dispersion capacity and expected life, respectively, were evaluated. Results confirmed the importance of developing a model that properly represents behavior of unconfined materials.