Evaluation of Proprietary Rejuvenators

Among the numerous alternatives for flexible pavement preservation, spray-applied rejuvenator seals have been gaining wide acceptance because of their advantages over the other treatments. Perhaps the most attractive features of the rejuvenator seals are their relatively low cost, speed of application, and limited impact on the traffic. Spray-on rejuvenators are used to (i) reverse/retard aging, (ii) seal cracks (slow down crack growth), (iii) reduce permeability (to protect the underlying layers), (iv) enhance friction, aesthetics and ride quality. Traditionally, ingredients of the rejuvenators include oils, plasticizers, and anti-stripping agents. However, numerous rejuvenators are currently marketed by the pavement industry, which includes petroleum-based and bio-based products. Formulations of most of these rejuvenators are proprietary, and there is a need for a thorough assessment of these products. The objectives of this research are to provide answers to the questions including (but not limited to) (i) when to/not to use each rejuvenator?, (ii) what are the pros and cons of each product?, (iii) what are the unit costs?, (iv) how do they perform relative to their intended use (e.g., retard aging, seal cracks, etc.)?, (v) are there construction issues?, (vi) how fast the traffic can be opened after the application?, and (vii) what are the impacts on the pavement markings?. Local agencies and MnDOT will gain significant benefits from the results of thorough research on these products. The outcome will assist in making more informed decisions on the three ‘Rs’ – the right treatment on the right pavement at the right time.