Validation of the mix design process for cold in-place rehabilitation using foamed asphalt

Description:

Asphalt pavement recycling has grown dramatically over the last few years as a viable technology to rehabilitate existing asphalt pavements. Iowa's current Cold In-place Recycling (CIR) practice utilizes a generic recipe specification to define the characteristic of the CIR mixture. As CIR continues to evolve, the desire to place CIR mixture with specific engineering properties requires the use of a mix design process. A new mix design procedure was developed for Cold In-place Recycling using foamed asphalt (CIR-foam) in consideration of its predicted field performance. The new laboratory mix design process was validated against various Reclaimed Asphalt Pavement (RAP) materials to determine its consistency over a wide range of RAP materials available throughout Iowa. The performance tests, which include dynamic modulus test, dynamic creep test and raveling test, were conducted to evaluate the consistency of a new CIR-foam mix design process to ensure reliable mixture performance over a wide range of traffic and climate conditions. The "lab designed" CIR will allow the pavement designer to take the properties of the CIR into account when determining the overlay thickness.

subjects: Asphalt Pavements,  Creep tests,  Dynamic modulus of elasticity,  Foamed asphalt,  Foamed materials,  Pavements, Asphalt,  Recycling,  Stripping (Pavements)