The preparation of surfaces for spray seal applications is of utmost importance. During the maintenance period of existing seal applications patching would have been done where surface defects were repaired. Cold-mix asphalt is often used for temporary patches. Cold mixes therefore play an important role in sprayed seal applications, both in preparation for new applications and the maintenance of the seal afterwards. The main objective of this study was to evaluate performance of proprietary cold mix asphalts available in South Africa. Five products were used in this study and engineering properties of products were investigated, including volumetric properties, permeability and indirect tensile strength. Performance properties were evaluated with the use of accelerated pavement testing using model mobile load simulator (MMLS3). It was found out that all five products have high void contents showing that cold mixes are highly permeable. Indirect tensile strength values were found to be very low compared to minimum value of 800 kilopascals specified for hot-mix asphalt. Products with emulsion as binder were found to be more susceptible to water damage compared to other mixes with cutback binder. In general all products are very highly susceptible to rutting compared to hot-mix asphalt. (a) For the covering entry of this conference, please see ITRD abstract no. E217099.
Abstract