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This research investigates if bottom ash produced by incinerating municipal solid waste after recovery of metals and aging (weathering) can be used as a substitute for natural aggregates in the manufacture of concrete without additional treatment, rather than being disposed of in landfill. In this research, the performance of eight concrete mixtures that contained different amounts (0–100%) of MSWI bottom ash was analysed. Mixtures were produced by fully replacing coarse aggregate, fine aggregate, and then both of them with MSWI bottom ash and mixing with two amounts (340 and 300 kg/m3) of cement (CEM I 42.5 R). Reference mixtures were produced as well. The influence of MSWI bottom ash as aggregate on concrete performance was evaluated in terms of density, compressive strength and flexural strength. The effect of cement content was investigated as well. In addition, the changes in density and compressive strength after 2 days, 7 days and 28 days were analysed. The research showed that concrete with a compressive strength class of C20/25 and bending strength of 3.4–4.3 MPa can be produced by fully replacing coarse or fine aggregate. To achieve this, at least 340 kg/m3 of cement is required. [ABSTRACT FROM AUTHOR]

[Display omitted] • The use of fiber or both silica fume and fiber improves concrete performance. • Steel fiber are superior to polypropylene fiber. • The use of silica fume and fiber allows to reduce the thickness of slab. • Concrete with 25.2 kg/m3 silica fume and 49.5 kg/m3 steel fiber showed best results. The main objective of this research is to develop high-strength concrete mixture (compressive strength ≥ 41 MPa) that is resistant to fatigue and suitable to produce slabs for modular pavements also known as precast concrete pavements. In addition to this, other characteristics (compressive strength, flexural strength and indirect tensile strength) were determined as well and the effect of fibers depending on type and amount in the presence and absence of silica fume has been revealed. Silica fume (0% and 7% by cement mass) and three types of fibers (one type of steel fibers and two types of polypropylene fibers) with three different amount of each fiber type were used to produce concrete mixtures. At all, 20 concrete mixtures were produced and tested in terms of static and cyclic bending, static compression and static tension. The research showed that the use of both fibers and silica fume in the concrete mixture leads to the best performance and steel fibers are superior to polypropylene fibers. Concrete mixture with 49.5 kg/m3 of steel fibers and 7% of silica fume by cement mass had compressive strength of 61 MPa and the highest resistance to fatigue and thus is the most potential to produce slabs for modular pavements. [ABSTRACT FROM AUTHOR]