Friction and Surface Texture Evaluation of Green-Colored Bike Lanes

1 2 Interest in colored treatment on bicycle lanes and crossings has been growing in the United States 3 in recent years. In comparison, this practice, has been prevalent in European cities for longer time. 4 It was not until 2011 that the green colored treatment received official interim approval from the 5 Federal Highway Administration (FHWA) for experimental use on bicycle facilities across the 6 country (1). This study focused primarily on evaluating the friction and texture characteristics of 7 five (5) independent green colored bicycle lane projects consisting of either (1) Epoxy Modified, 8 (2) Thermoplastic, or (3) High Friction Surface Treatment materials in Florida. A total of three 9 types of existing pavement surfaces (concrete, open and dense graded asphalt pavements) were 10 used as substrate for the colored application. These chosen sites include both control test sections 11 representing the bike lanes with limited/no traffic interaction and keyhole sections that represent 12 traffic conflict areas (areas where bicycles and vehicles come into conflict). The friction and 13 texture values were obtained using the Dynamic Friction Tester (DFT) and Circular Texture Meter 14 (CTM), respectively. Results indicated that all green bike lane projects met the initial friction 15 number requirements for Florida’s Patterned Textured Pavements. Minor friction loss was 16 observed at the keyhole sections when compared to the control sections indicative of traffic wear 17 effects. Factorial Analysis of Variance (ANOVA) showed that factors such as pavement surface 18 type as well as type of green bike lane material applied and the presence of traffic wear have 19 significant influence on the friction values. In addition, based on mean profile depth (MPD) 20 measurements, only the interaction of pavement surface type and the bike lane treatment type had 21 significant impact on the texture. The presence of traffic was not a significant factor. All these 22 results ultimately lead to new design criteria in 2016 permitting a more wide-spread application of 23 green colored bike lanes on the Florida State Highway System. 24 25