Evaluating pavement support alternatives for precast concrete inlay panels

Precast concrete pavement can achieve excellent long-term performance when constructed with stable, uniform support underneath the panels. Precast concrete inlay panels (PCIP) are a unique type of precast pavement, developed to rehabilitate rutted high-volume asphalt highways. A trial section of PCIP was installed on Highway 400 in Ontario, Canada in 2016 using three different types of panel support conditions called asphalt-supported, grade-supported, and grout-supported that are prepared at the asphalt-panel interface. The purpose of this research is to evaluate the performance of PCIP with different support conditions under a combination of axle loading and linear temperature gradients. Three-dimensional models of the PCIP were created using Abaqus software. One model was developed to represent the asphalt-supported condition (AS) and a second model represents the grade- and grout-supported conditions (GR). Parametric studies were performed to evaluate the critical stresses in the loaded panel for the AS and GR models. The study considered different values of the elastic modulus for the asphalt and support and varied degrees of bonding between the panels, support, and asphalt layers. The GR models had lower or comparable stresses than the AS model, and higher degrees of bonding reduced the critical stresses. Overall, a grout-supported condition with a stiff support and a higher degree of bonding between the panel-to-support and support-to-asphalt layers is recommended to minimize the critical panel stresses under combined axle loading and a temperature gradient, based on the scope of this study.