The pore-water pressure generated by intermittent dynamic vehicle loading under various saturation states is recognized as a critical factor influencing the behaviour of permeable pavement structures, especially the behaviour of UGB layer. However, the underlying mechanisms of hydro-mechanical interaction in the UGB layer and the influence on the pavement structure are still unclear. This study aims to characterize the changes in dynamic response in permeable pavement structures under various saturation conditions by considering the hydro-mechanical interaction within the UGB layer. To achieve this objective, a full-scale test track with a PUPM wearing course was constructed. Pressures and water distribution were characterized by embedded sensors within different layers of the test track when subjected to the accelerating pavement test. Based on the coupled SAME model, the water distribution and the dynamic response of UGB in the rainfall events were both characterised and solved by FEM. The results predicted by the proposed SAME model correspond to the field measurements, and the influence of the water content on the resilient modulus distribution within the UGB layer was then estimated. Based on the predictions for the stress state of the UGB layer, the sensitivity analysis was also proposed.

Permeable pavements have been widely used as an effective means to improve hydrological characteristics and the ecology of the urban environment. This study aims to investigate the response of fully permeable pavement (FPP) subjected to dynamic loading under dry and saturated conditions. A full-scale test track topped with polyurethane bound permeable material (PUPM) was built to obtain the stress response with an accelerated pavement test (APT) system. In addition, comprehensive analyses were performed based on the coupled Stress-dependent Moisture-sensitive Cross-anisotropic Elastoplastic (SMAEP) model in FEM. The APT test showed that the worst state was observed when the pavement structure was fully saturated, and that and brittle failure of the pavement surface occurred when the critical load level was achieved. The prediction of vertical stress predicted by Stress-dependent Cross-anisotropic Elastic (SAE) and SMAEP were both validated with the field data. The horizontal stress predicted by SAE gave a very high and unreasonable tensile stress prediction at the bottom of the unbounded granular base (UGB) layer when subjected to the high load level. With the consideration of moisture effect and the plastic properties of the material, the prediction made by SMAEP is effective to estimate the dynamic response of the UGB layer. Based on the sensitivity analysis, the optimized designs for FPP based on PUPM were suggested.