Evaluating the rheological properties of PMB-containing RA binders from surface-layer asphalt mixtures to be recycled

A rapidly increasing source of reclaimed asphalt (RA) that contains polymer modified bitumen (PMB) offers a potential premium material contribution when performing recycling. This study investigated the rheological properties of three PMB-containing RA binders from different “old” surface-layer asphalt mixtures in Europe and their impacts on “new” binders after blending with soft virgin paving grade or PMB binder. Three main results can be found: although it degrades during the service life of asphalt pavement, reclaimed binders still contain residual polymer characteristics; for mixture design in the industry, the logPen. model and the linear S.P. model can be used to predict blending effect approximately; the virgin binder dominates rheological properties of blended binder, except that the stiff RA binder from porous asphalt plays a role at a high content of 40%.