This report describes work to investigate sealing aggregate bonding to standard and polymer modified bituminous binders.
The work included investigation of the variation of adhesion strength for different aggregate surfaces, the effect of water on binder-aggregate bonding, and development of a test for measuring binder spreading rate on plane surfaces.
The spreading rate test was generalised to rough surfaces, and results fitted to power law equations for degree of spreading.
This test has the potential to become a standard method for evaluating aggregate-binder adhesion, but further work with various aggregate surfaces and comparison with field-trial results is needed to achieve this.
Keywords: adhesion, aggregate, bitumen, chipseals, polymer, modified binders, roads, wetting