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The paper focuses on the issue of using reclaimed asphalt (RA) in asphalt mixtures used for highly traffic-loaded asphalt pavements—in asphalt mixtures of the stone mastic asphalt (SMA) type. It is a skeleton-type mixture, where the traffic load is bore by a skeleton of coarse aggregates bonded with mastic (i.e., bitumen and fine aggregates). It is therefore essential to pay close attention to the properties of this coarse aggregate. Higher demands on properties of the aggregate are probably due to the fact that RA is not currently being used in SMA-type mixtures. Most standards do not allow usage of RA in this type of mixtures. Given that traffic load of road networks is constantly increasing, the ratio of SMA-type asphalt mixtures also increases in the road network. This paper presents results of 5-year research focused on the possibility of using RA in SMA-type asphalt mixtures. This included laboratory design of these mixtures with various dosages and types of RA. Their empirical and functional properties were verified. Based on the positive results of the laboratory testing, a test section was subsequently constructed using several variants of the mixtures containing up to 50% of RA. This test section is regularly being monitored, and despite very intense traffic load, there are no failures apparent after 2 and half years of operation. Based on the laboratory research and subsequent construction and monitoring of a test section, it can be said that RA can be used in SMA-type mixtures without any negative impacts on functional properties or mixture lifetime.

The effect of compaction degree and binder content on performance properties of asphalt mixtures of an asphalt concrete type for wearing and binder courses are described in the paper. Measurements of stiffness modulus by two-point bending test on trapezoidal shaped specimens, fatigue characteristics, and resistance against frost cracking by thermal stress restrained specimen test have been performed on selected asphalt mixtures. The main aim of the experimental part was to determine to what extent the performance properties of the individual mixtures will be affected when decreasing the compaction degree by 3% in comparison to the optimal design, i.e. from 100% to 97% degree of compaction. This decrease simulates incomplete degree of compaction of courses during pavement construction, which is common and accepted during acceptance tests and it is in accordance with the Czech regulations. Then, the decreased dosage of binder content by 0.5% is simulated, which is the boundary parameter for lowering the binder content within the acceptance test. The results of performance testing have been affected by lower compaction degree and lower binder content have been used as course parameters and integrated into a mathematical model of a commonly used pavement construction, which is presented by a multi-layered linear elastic model based on the use of Burmister‘s equations. The outcome of the paper is a description of the effect of lower degree of compaction and lower binder dosage on the lifetime of a pavement construction.