Theoretical Analysis of Design Parameters on Semi-Rigid Asphalt Pavement with Flexible Base

Reflective cracking is one of the main distresses for the cement/lime/flyash stabilized base in China. Although a flexible base can and has been utilized as a sandwich layer to reduce reflecting cracks from the stabilized base, the repetitive truck traffic load may cause higher tensile stress at the bottom of the asphalt surface course due to a large deformation from the flexible base. This high tensile stress may lead to fatigue cracking. To minimize the tensile stress at the bottom of the asphalt layer, and to establish optimum structure design parameters to reduce the maximum tensile stresses at the bottom of the asphalt surface course, a nonlinear, finite element technique was utilized to support the experimental pavement in the Tonghua Highway in the Jilin province. Based on the analyses, to minimize the tensile stress at the bottom of the asphalt layer, the value of the flexible base modulus should be more than 400MPa and that of semi-rigid, sub-base modulus should be more than 1500MPa, which can guide the design and construction of the semi-rigid asphalt pavement with a flexible base.