Accession Number : AD0823572

Title :   OXIDATIVE DEGRADATION OF ASPHALT.

Descriptive Note : Final rept. Jan 66-Jul 67,

Corporate Author : NAVAL CIVIL ENGINEERING LAB PORT HUENEME CA

Personal Author(s) : Vind, Harold P.

Report Date : SEP 1967

Pagination or Media Count : 20

Abstract : Knowledge that the deterioration of asphalt is primarily an oxidative process leads to three general approaches for preventing the deterioration of asphaltic construction mixtures: (1) Agents might be added or other measures might be employed to lower the intrinsic reactivity of asphalt with oxygen, even when the availability of oxygen is not limited; (2) Sacrifical oxygen-consuming agents might be added to the construction mixtures to limit the amount of oxygen available for reacting with the asphalt; (3) Impermeable surface coatings might be applied or fine particles might be added to clog or seal the pores, thereby retarding the diffusion of oxygen through the asphaltic mixtures. The three proposed approaches are applicable irrespective of the involvement of bacteria in the degradation of the asphaltic construction mixtures. Other measures for prolonging the service life of special asphaltic compositions might be the application of heat reflective white coatings to prevent solar heating, or the incorporation of water-absorbing additives to prevent penetration by water.

Descriptors :   *OXIDATION), (*ASPHALT, DEGRADATION), (*DEGRADATION, COATINGS, HEAT RESISTANT MATERIALS, SPECIFICATIONS, TEST METHODS, FAILURE(MECHANICS), RELIABILITY, PHOTOCHEMICAL REACTIONS, POLYMERIZATION, CATALYSTS, THERMAL PROPERTIES, EMBRITTLEMENT, ADDITIVES, CHEMICAL REACTIONS, GELS, TEMPERATURE, MOISTURE, ANTIOXIDANTS, MIXTURES, MICROORGANISMS, BACTERIA, PERMEABILITY.

Subject Categories : Miscellaneous Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE