Long-term Aging Properties of Bitumen With Expanded Vermiculite and Different Inorganic Nanoparticles

The authors evaluate a novel bitumen modification by using the expanded vermiculite (EVMt) and three inorganic nanoparticles. The effect of EVMt and inorganic nanoparticles on physical and long-term aging properties of bitumen was investigated. The results show that the physical properties of bitumen are slightly influenced by with the introduction of nanomaterials. As a result of pressurized aging vessel, ultraviolet (UV) radiation aging, the viscosity aging index of bitumen is decreased obviously by adding the nanomaterials. It indicates that nanomaterials can improve the thermal and UV aging resistance of bitumen simultaneously. Furthermore, this improvement depends on the inorganic nanoparticle types. Compared with nano-silica and nano-titanium dioxide modified bitumens, bitumen with 1% EVMt and 3% nano-zinc oxide shows the lower viscosity aging index values, indicating its good long-term aging resistance.