Evaluation of Moisture Susceptibility of High-Porosity ATPB Drainage Layer Materials Using Modified Dynamic Modulus Test

Abstract

AbstractAsphalt-treated permeable base (ATPB) mixtures have been widely applied for drainage layers in pavements to avoid moisture-induced problems in the United States. However, with frequent exposure to water, the ATPB drainage layer itself is at high risk of moisture damage. In this study, the dynamic modulus and phase angle are used as the indicators to evaluate the potential moisture-induced deterioration of typical ATPB materials adopted in Virginia and Oklahoma. The modified dynamic modulus test appropriate for testing drainage layer materials with moisture deterioration were determined and adopted. Comparisons between the dynamic modulus of the conditioned and unconditioned specimens primarily show that the moisture-induced dynamic modulus reduction tend to be larger as the voids in total mixture (VTM) increases, and the drainage layer materials may become more sensitive to VTM but less sensitive to temperature after being conditioned in moist environment. The investigation of phase angle ratio an...