In the marking construction, the amount of reflective glass beads should be moderate. Too little, there will be fewer reflective spots, and the reflective brightness of the marking will be poor; Too much, it is difficult to form retro reflection.
In the construction of road markings, the amount of glass beads sprinkled on the surface is likely to form "virtual beads". In this case, the reflective glass beads cannot adhere well to the markings and easily fall off from the marking surface. Before the "virtual beads" of the layer fall off, the marking lines have extremely poor reflection brightness at night, and the marking lines will appear darkened overall or locally.
Foreign research results show that when the part of the reflective glass beads embedded in the marking is 55% to 67% of the diameter of the glass bead's spherical surface, the light can almost completely retroreflect at this time.
For a single reflective glass bead, when the embedding degree of the glass bead is below 50%, the retroreflective effect that can be formed is extremely poor, and the light almost completely penetrates the glass bead and refracts; When the embedding degree of the glass bead is 60% left and right, the retro-reflective effect is the best; When the embedding degree increases again, the retro-reflective effect gradually decreases, because the amount of light entering the glass beads also decreases as the embedding degree of the glass beads increases. In actual construction, the distribution of glass beads rarely exists alone. But from a statistical point of view, the optical behavior of many glass beads is very similar to the behavior of a single glass bead under the above conditions.
The Use and Function of Glass Beads