Abstract:Hot mix asphalt (HMA) is the surface type for approximately 75 percent of the California state highway network and a widely used structural material in a number of different pavement applications. Reclaimed asphalt pavement (RAP) is HMA that is milled off the existing surface and can be used to partially replace virgin asphalt binder and aggregate in new HMA. Currently, a maximum of 25 percent RAP by weight of mix is allowed in HMA by Caltrans. The goal of this study is to use the life cycle assessment (LCA) methodology and quantify the changes in greenhouse gas emissions (GHG) and other environmental impacts by allowing RAP contents of up to 25 percent, as allowed under a recent change in specification that will facilitate this, and then up to 40 and 50 percent in HMA, considering virgin binder replacement, versus the recent practice of 15 percent. Sensitivity analysis considers alternative rejuvenating agents based on assumed inventories.