Numerical analysis for the influence of saturation on the base course of permeable pavement with a novel polyurethane binder

Permeable pavements represent an effective approach to optimize the conventional sealed pavement infrastructure. Compared to sealed pavement structures, the porous pavement structure allows fluids to pass through it freely, reducing and controlling runoff in the surrounding area. The stress state of this pavement system under different saturation conditions is one of the most important challenges for the pavement design. This study aims to develop a modulus-reduction method for the pavement material under different saturation conditions by considering hydro-mechanical interaction. To achieve this, a full-scale permeable test track was constructed in this study. A falling weight deflectometer (FWD) was used to measure the deflection of the test track at different saturation states. Using the back-calculated elastic parameters, tire-pavement interaction models were created to conduct finite element method (FEM) simulations of the stress state of the test track subjected to the loads from Accelerated Pavement Testing (APT). The results show that the hydro-mechanical properties of the test track are significantly affected by the water content. As a result, the current design algorithm of fully permeable pavements should consider the effects of saturation to allow for improved designs of fully permeable pavements.