| Open-graded friction course (OGFC) is a porous mix primarily used to improve pavement safety. OGFC is characterized by air voids ranging from 15 to 20 percent which allows surface water to drain through its structure and then laterally from the pavement structure. The ability of OGFC to drain water quickly results in less water ponding on the pavement surface, thereby reducing hydroplaning, reducing vehicle spray, and providing improved skid resistance. Research objectives were to evaluate the use of OGFC mixes containing 100 percent gravel and 50 percent gravel/50 percent limestone and to determine specifications to be employed by the Mississippi Department of Transportation (MDOT). Specimens were prepared at design asphalt binder content and evaluated for permeability, durability, stability, and moisture resistance. Research findings show mixes containing 100 percent gravel and 50 percent gravel/50 percent limestone perform comparably in laboratory testing. |
