Improving the compressive strengths of cold-mix asphalt using asphalt emulsion modified by polyvinyl acetate

Rut is the type of flexible pavement distress mostly occurring in Mexico, generally caused by exceedingly heavy axle loads. Therefore, the compressive strengths of cold-mix asphalt (CMA) must be improved, for this reason a polyvinyl acetate emulsion (PVAC-E) was added to a cationic quick set emulsified asphalt to obtain a modified asphalt emulsion that was mixed with a local aggregate in order to prepare two types of CMA. In the type I mix, aggregates were coated by a film of asphalt-polyvinyl acetate (A-PVAC) binder. In the type II mix, before the A-PVAC binder was layered, the aggregate was covered with the polymer by mixing the aggregate in a diluted PVAC-E. Since the microparticles of the polyvinyl acetate were well dispersed in the asphalt paving mixture matrix for modified CMA type II, the compressive strengths of test specimens were improved by 31%, compared to the values obtained with the unmodified CMA. (c) 2005 Elsevier Ltd. All rights reserved.