In Colombia, the granular materials of high quality for the conformation of flexible pavements structures are of difficult obtaining. In some cases the Engineer of highways must work with granular materials that do not fulfill the requirements of minimum quality standards of the pertinent road specification. In this case the Engineer must try to improve the properties of the material either. In the present investigation, PVC remainders were used like adding material, to modify the behavior of a granular subbase. From tests of Proctor and CBR, the behavior of the natural and mixed material with different proportions of the PVC remainder was compared. The results of the investigation shown that the CBR of a mixture of granular material type subbase and the remainder material, present a remarkable increment. In addition, the modified mixture manages to modify the unitary weight of the material, obtaining a mixture with greater resistance and minor unitary weight.