Design approach for granular emulsion mixes (GEMS)

Abstract

Granular Emulsion Mixes (GEMS) are used in a wide range or road applications, ranging from low volume roads in developing areas to freeways in developing urban areas. In this paper a dual design approach for granular emulsion mixes (GEMS) is presented. An “asphalt” approach is used in the design of stabilised GEMS with residual binder contents of more than 1,5%, using design methods such as the Marshall mix design method. A “gravel” approach is used in the design of modified GEMS with residual binder contents of less than 1,5%, using test methods such as the California Bearing Ratio test method. The mix and structural design procedures for both approaches are discussed. The research was done on behalf of the Southern African Bitumen and Tar Association