Laboratory Evaluation of Asphalt Cement and Mixture Modified by Bio-Char Produced through Fast Pyrolysis

In this paper, fractionated bio-char, a carbonaceous co-product from bio-fuel production, is utilized as an asphalt modifier. Laboratory testing was conducted to evaluate the modification effect of bio-char on asphalt cement and mixture. The bio-char used in this study was derived from switch grass and produced through a fast pyrolysis method. The binder samples, made by incorporating bio-char into one commonly used asphalt binder in the U.S., were tested for their rheological characteristics, rutting, and fatigue performance. It was found that bio-char was capable of significantly increasing the rutting resistance of the asphalt binder. The fatigue and cracking resistance was little affected by modification. The modified HMA mixture showed better resistance in rutting, moisture damage and cracking.