A Field and Laboratory Based Study to Ascertain Degradation in The Signage Retro Reflectivity
A little attention has been paid on the quality of reflective sheeting used for road signs in the past. Moreover, significant number of road accidents recorded during the nights, have been attributed to sign aging and accumulation of dirt deposit. A research study was thus undertaken to evaluate the performance of different sign’s sheeting brands, grades and color installed on national Highways (N-5) and Motorways (M-1 and M-2). The aim of this research study was to assess the aging of sign sheeting. Laboratory and field retroreflective measurements of sign sheeting were taken with portable handheld equipment retro-reflectometer at different orientations and observation angle.Aging Characteristics and impact of sign cleaning were also studied in addition to sign life cycle cost analysis. It was noticed that Coefficient of retroreflectivity varied greatly with Instrument rotations and observation angles. A linear trend in the rate of reduction of coefficient of retroreflectivity with age has been observed in the field. Also, retroreflection improved by 13-20 % on an average for various sheeting brands and grades maintaining the signs.
Index Terms: Transportation Engineering, Traffic safety, Traffic Signs, Retroreflectivity.