ABSTRACT
The study evaluates the effect of glass fibre grids, used to reinforce asphalt structures, on the bonding strength between a wearing and a binder course. For this purpose, a test surface consisting of a 6 cm thick binder (0/16 mm) and a 6 cm thick wearing course (0/10 mm) was built. Four different grids coated with various quantities of the bitumen emulsions C60B4-S and C40B5-S were used. Comparison sections were made without grid but also coated with different quantities of emulsions. Extracted cores with a 150 mm diameter were tested at ambient laboratory temperature with a monotonous shear test (LEUTNER). Displacement, shear force and shear stress were measured. The influence of grid characteristics, the existence of a non-woven and the size of the strands as well as the effect of different emulsions on the shear bonding strength were observed. We find that the tests without a reinforcement grid reach more important values of stress at failure and that the decrease in shear stress levels at failure is more important for bigger grid sections.
