WETTING STUDIES ON SILICATE MINERALS AND ROCKS USED IN BITUMINOUS HIGHWAYS

A study has been made on the wetting characteristics of quartz and several other silicate minerals and road stones used in bituminous roads. From contact angle measurements using the "two-liquid phase" method the non-dispersive interaction energy between the mineral or road stone and water (I(sw)p) with and without heat treatment was obtained. The results indicate a wide range of I(sw)p values, which appear to depend on the chemical composition of the aggregate. It was also suggested that the result may be related to the degree of contamination. From these studies it also appears that I(sw)p is a useful parameter defining the vulnerability of stripping.