Geocomposites against Reflective Cracking in Asphalt Pavements: Laboratory Simulation and Field Application

Asphalt pavements often suffer reflective cracking phenomena. Crack appearance at the road surface leads to several detrimental effects, including the loss of watertightness. Geocomposites, such as grid-reinforced bituminous membranes, represent an efficient method against reflective cracking since they combine improved tensile properties of grids and stress-relieving effects of membranes. Moreover, membranes allow pavement waterproofing. This paper presents laboratory and field studies carried out to investigate the reflective cracking resistance of geocomposite-reinforced asphalt systems. The study is based on a real-scale field trial constructed along an in-service motorway. Five geocomposites were taken into account and the possible use of a tack coat and application on a milled surface were also evaluated. Interface shear tests were carried out both on field cores and on laboratory-made samples. Moreover, pre-notched laboratory specimens were subjected to specifically-developed simulative tests through the Wheel Tracking equipment. Experimental results clearly showed that a proper selection and application of optimized grid-reinforced bituminous membranes can significantly enhance reflective cracking resistance of asphalt pavements.