Abstract: A combination of antioxidants and method of incorporating the antioxidants into an asphalt binder to make a modified asphalt binder are described. The antioxidants comprise a thioester and an aldehyde. The aldehyde and thioester, in a ratio between about 1:100 and about 100:1 parts by weight, are added to an asphalt binder. An acidic catalyst is also added in a concentration between about 0.1 wt % and about 18 wt % of the asphalt binder. The antioxidants, asphalt binder, and catalyst are mixed at a temperature between about 85° C. and about 135° C. for a time between about 30 minutes and about 6 hours. The antioxidants are capable of improving the performance grade of the asphalt binder. The modified asphalt binder possesses superior resistance to oxidative age hardening compared to other modified asphalt binder compositions that incorporate various antioxidants.

Abstract: A combination of antioxidants and method of incorporating the antioxidants into an asphalt binder to make a modified asphalt binder are described. The antioxidants comprise a thioester and an aldehyde. The aldehyde and thioester, in a ratio between about 1:100 and about 100:1, are added to an asphalt binder. An acidic catalyst is also added in a concentration between about 0.1 wt % and about 18 wt % of the asphalt binder. The antioxidants, asphalt binder, and catalyst are mixed at a temperature between about 85° C. and about 135° C. for a time between about 30 minutes and about 6 hours. The antioxidants are capable of improving the performance grade of the asphalt binder. The modified asphalt binder possesses superior resistance to oxidative age hardening compared to other modified asphalt binder compositions that incorporate various antioxidants.

Abstract: A combination of antioxidants and method of incorporating the antioxidants into an asphalt binder to make a modified asphalt binder are described. The antioxidants comprise a thioester and an aldehyde. The aldehyde and thioester, in a ratio between about 1:100 and about 100:1, are added to an asphalt binder. An acidic catalyst is also added in a concentration between about 0.1 wt % and about 18 wt % of the asphalt binder. The antioxidants, asphalt binder, and catalyst are mixed at a temperature between about 85° C. and about 135° C. for a time between about 30 minutes and about 6 hours. The antioxidants are capable of improving the performance grade of the asphalt binder. The modified asphalt binder possesses superior resistance to oxidative age hardening compared to other modified asphalt binder compositions that incorporate various antioxidants.

Abstract: A hollow cylindrical tester uses an inflatable membrane to apply hoop stress to a hollow cylindrical sample. The compact device includes a frame that holds a sample around the inflatable membrane. The membrane is preferably inflated via fluid pressure and the fluid pressure preferably is monitored to determined pressure at critical points in testing procedures. Pressures of fluids within the membrane are also monitored. In a preferred structure, a piston and cylinder pressure injector operatively connected to the membrane is monitored for amount of piston travel and a pressure meter monitors fluid pressure. The preferred structure includes shaped opposing platens to seal the membrane within a cylinder sample being tested, a post failure restraint cylinder, and a cooling fluid bath.

Abstract: A hollow cylindrical tester uses an inflatable membrane to apply hoop stress to a hollow cylindrical sample. The compact device includes a frame that holds a sample around the inflatable membrane. The membrane is preferably inflated via fluid pressure and the fluid pressure preferably is monitored to determined pressure at critical points in testing procedures. Pressures of fluids within the membrane are also monitored. In a preferred structure, a piston and cylinder pressure injector operatively connected to the membrane is monitored for amount of piston travel and a pressure meter monitors fluid pressure. The preferred structure includes shaped opposing platens to seal the membrane within a cylinder sample being tested, a post failure restraint cylinder, and a cooling fluid bath.