Application of statistical methods for quality evaluation of asphalt concrete mixture production

Abstract

Mathematical models revealing the ideal structural homogeneity of asphalt concrete, shown by uniform distribution of its mineral components (coarse aggregate, fine aggregate, filler) and bitumen, are presented. The asphalt concrete structure is proposed to be investigated as a whole of three levels (asphalt binder, asphalt mastic, asphalt concrete mixture) of incomplete, optimal and smallest structural elements of the structure, consisting of grains of various diameters as well as adhesive films of oriented and volumetric bitumen. It is demonstrated that it is not always possible to produce an asphalt concrete mixture conforming to the project composition and standard physical-mechanical parameters due to technological errors. Mathematical models, showing technological factors and their impact on the quantity of components in the mixture, were constructed based on the factual homogeneity of asphalt concrete mixture identified by statistical methods. The additive model consists of variance, which depend on the stability of the used aggregate grading, their dosing errors and the quality of mixing. Average variance of mineral components‘ quantities in the produced asphalt concrete mixture as well as the impact in per cent of comprising technological factors were calculated from experimental data. The most important trends of technology upgrading, the practical application of which may considerably improve the quality of asphalt concrete mixture production were substantiated.