Thickness Design of Asphalt Layer Based on Dynamic Modulus

In China, the static creep modulus of hot-mix asphalt (HMA) was utilized to calculate the resilient deflection and tensile stress in asphalt pavement for structural thickness design. However, the static creep modulus does not match the stress and strain performance of HMA. In this paper, the dynamic modulus of HMA was studied by means of the modified loading time and the theoretical analysis and laboratory experiments. A field construction pavement structure, namely the connecting highway between Shiwu high-speed railway station and the Dawu County, was used to calculate the strain at the bottom of asphalt layer under the measured dynamic modulus by three-dimensional finite element(FE) software (i.e., ANSYS). According to China's specification, the dynamic modulus testing was carried out for the materials of this highway. The results of calculating and analysis indicated that the mechanical responses in asphalt pavement were different and the dynamic modulus should be used for the thickness design of the asphalt layer in China.