EVALUATION OF STRUCTURED METHYL METHACRYLATE MARKING TO INCREASE PAINT CONSPICUITY
The Federal Aviation Administration (FAA) Office of Aviation Research, Airport Technology Research and Development Section, in response to a request for research from the FAA Office of Airport Safety and Standards, Airport Engineering Division, undertook this research effort to determine if a new application technique for painting pavement markings would increase conspicuity over the useful life of the marking.
A paint manufacturer presented the FAA with information on a new paint marking called structured methyl methacrylate (SMMA). Methyl methacrylate (MMA), paint without the structured component, is currently approved for use on runways and taxiways. SMMA differs from traditional MMA because it is applied using a splatter pattern. When applied to a pavement using the splattered application technique, SMMA creates a thicker, textured surface with peaks and valleys, while still creating a visible solid line. The manufacturer claims this application technique will enhance wet, nighttime retro-reflectivity by allowing water to flow off the peaks and into the valleys of the marking, thus making the paint and beads on the peaks more visible. The manufacturer also suggested using a slightly modified paint formula, which will provide enhanced visibility when used with this unique application technique.
The research objective was to compare the suggested SMMA paint to traditional MMA paint, and further evaluate whether the proposed splatter application technique, thicker application, and modified formula offer improvements over the currently accepted MMA application techniques and formula. A complex test plan, containing a variety of tests, enabled researchers to evaluate each element that makes up the SMMA paint markings. Testing activities included retro-reflectivity, chromaticity (color), friction, pull-off strength, water run-off, and heavy vehicle simulator studies.
The results of this research effort were favorable, indicating that the new SMMA paint, when used with Type III glass beads, showed an improvement over conventionally installed MMA markings. Although the SMMA paint does not fully cover the pavement surface, the material does appear to be a continuous marking when viewed from a distance. The SMMA paint possessed higher friction values, shed water faster, and improved the visibility of the paint marking over the conventional MMA markings. The modified, softer paint formula proposed by one manufacturer did not appear to have any adverse effect on the SMMA paint markings.
DOT/FAA/TC-TN15/50
Authors: Holly M. Cyrus and James Patterson, Jr.