Many pavement marking materials in common use lose their effectiveness to a marked degree during periods of darkness in adverse weather conditions approaches the effectiveness provided under normal conditions. In this study, ways of improving delineation of roadways under wet and dry conditions by either improving techniques utilizing existing materials or developing new materials and techniques were investigated. Glass beads as used in pavement marking materials perform in the highway environment in relation to many variables, some of which include their composition, surface treatment, diameter, gradation rate of application, surface on which they are applied, the depth of embedment in the binder, orientation of the binder with the light source, refractive index, shape, imperfections, method of application, the type of failure of the binder, and the covering water films encountered during periods of precipitation. Raised refectories markers perform in the highway environment in relation to may of the same influence as binders refectories with glass beads; however, they represent a different technology and are subject to other external influences. By taking into consideration the many variables that influence the performance of marking materials, it is possible to select not one but several techniques for improving the performance of pavement marking materials in the day and night, wet and dry conditions. More specifically, and attempt has been made for approaching the problem of marking pavements in a systematic manner where in one qualifies the surface to be marked, determines the water film thickness to be encountered and then selects one of several marking systems that will perform under the imposed conditions.
Samenvatting