Mechanical Stabilization of Intermediate Granular Layers in Pavement Structures - Laboratory Study

A laboratory study aimed at the influence of a stiff geogrid placed on the intermediate granular layer between a cracked concrete base and the top asphalt layer was carried out. Five physical models 2x1x0.8m in size have been studied under cycling loading up to 2 million cycles. The paper describes the application of the crack propagation barrier with various layer thicknesses. The asphalt surface settlement, the movement of concrete panels and visual control of crack propagation was monitored during the loading of each model construction. After the loading termination, cylindrical cores were taken passing through the asphalt layer and the asphalt surface relief was evaluated. The achieved results were mutually compared and the optimal composition of layers was identified. Mechanical interlocking has been proven as the ruling mechanism of the stabilisation function and prevention of reflective cracking.