Road markings are a significant traffic management aid, in terms of road safety and the orderly flow of traffic, and now account for over $3 million of the Departmental annual budget. For a number of years, the paints used for almost all marking applications in South Australia have been of the alkyd resin, solvent-borne type. These paints contain a high volume (greater than 50 percent) of hydrocarbon solvents. Water-borne road marking paints have been used in the USA for some years, purportedly with good results. The benefits reported have included greater durability, retroreflectivity and significantly reduced environmental impact. However, there is little published information on the field performance of the field performance of water-borne paint markings. The effect of paint and glass bead application rates on retroreflectivity and wear of water-borne paint markings was investigated. Available data indicate that water-borne road marking paints are ready for introduction for day to day marking operations in South Australia, as a cost effective replacement for solvent-borne paint. Additional benefits would accrue from decreased use of glass beads, elimination of toluene usage, reduced disposal costs, greater worker's safety and reduced environmental impact. Operational considerations are also discussed. (A)
Abstract