Design with Fiber Reinforcement for Thin Concrete Overlays Bonded to Asphalt

Abstract

A thin concrete overlay bonded to asphalt pavement design approach has been developed by extending an existing ultrathin whitetopping (UTW) design method. A significant contribution to this proposed design method is the incorporation of fiber reinforcement into the structural design and concrete material specification, through the implementation of a residual strength ratio requirement. Climate and traffic inputs were simplified through the use of an equivalent temperature gradient and equivalent single-axle loads (ESALs). A probabilistic concrete fatigue algorithm was also used to allow engineers to select the appropriate level of reliability and the amount of cracking for the UTW project. The new concrete overlay design method is most influenced by the concrete flexural strength, fiber-reinforcement residual strength, slab size, traffic, and the underlying asphalt condition and thickness.