Influence of the Composition of Asphalt Granular Concrete Mixture on the Deformation of the Coating Layer During the Construction of the Road Pavement

Abstract

Statement of the problem. The introduction of cement into the composition of the bitumen emulsion at the stage of preparation affects not only the strength of the layer, but also the properties of the asphalt granular concrete mixture, which must be taken into account when developing technological processes for compaction. Under the action of the compacting load, taking into account the content of cement in the binder material, the deformability and rigidity of the compacted layer change. The change in the rigidity of the layer affects the choice of parameters of compacting machines. Therefore, whiledeveloping a pavement technology using asphalt-granular concrete mixes using combined binders, it is necessary to establish the effect of cement content on the deformability and rigidity of the compacted layer. Results. The results on the influence of the cement content in the combined binder in the asphalt-granular concrete mix on the deformability of the layer under the action of the compacting load are presented. Dependences were obtained to determine the residual deformation and rigidity of the mix layer under the action of a load, taking into account the layer thickness and cement content. Conclusions. The use of a combined binder (bitumen emulsion and cement), depending on the cement content, leads to a decrease in the deformability of the layer of asphalt granular concrete mixture up to 40 %, regardless of the size of the granulate fractions and the thickness of the layer during laying, as well as an increase in the rigidity of the layer from 1.8 to 2.1 times, which must be taken into account when choosing the parameters of the rollers in the compaction process.