This graduation thesis is concerned with the development of a fly ash based aggregate by
means of the cold-bonding process, by casting and then crushing into individual fractions.
Three different proportions of Portland cement, i.e. 10%, 20%, and 30%, were used in the
mixture as a binder. Prior to use, the chemical and mineral characteristics of the fly ash were
determined, as well as the corresponding loss of ignition. The comparative aggregate was
developed by means of the cold bonding pelletization process. Based on the results of tests
of the tensile and compressive strengths of the crushed aggregate, a cement ratio of 10 %
was used in this process. Density, water adsorption capacity, and porosity, as well as tensile
and compressive strengths, were determined for the produced aggregates after aging them
at constant humidity. SEM investigations were also performed, and the results obtained in
the case of both produced aggregates were compared. In order to assess performance of the
aggregates in practice, both of them were used in concrete, and the results of tensile and
compressive strength tests were compared with those achieved in the case when the
concrete was made using limestone aggregate.
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