Application of similarity method of distance courses describing the elements content in typical cement concrete after thermal cycles

The work concerns the use of similarity analysis of distance course. Composition of concrete mixes was designed. The cement concrete composition includes cement, coarse aggregate, fine aggregate, water and admixtures. The laboratory analyses included concretes curing in standard conditions and concretes subject to thermal cycles representing the destructive influence of imposed loading. Laboratory tests assumed the fifty thermal test cycles. A single test cycle included process of alternate heating and cooling. Recurrent influence of temperature stimulated the impact of aircraft on airfield pavements. The assumed heating and cooling time corresponded to the time during which the aircraft effected the most frequently used airfield pavement within the area of Poland. Comparative SEM observations of concretes subject to thermal cycles were conducted. An increase in the width of microcracs has been observed. In case of crystallization, there is diversification within the area of cement matrix, contact area between cement matrix and aggregate grains and in case of porosity characteristics of both concretes. Similarity indexes between input and target sequence were defined. Diagrams presenting the similarity of the analysed concretes were prepared (after 28 days of curing and after thermal cycles). It was proved that the suggested method could be used to define the similarity of concrete intended for airfield pavements.