Acta Scientiarum Polonorum

Concrete, being one of the most important construction materials, despite many advantages (ease of handling,
high compressive strength, low production cost, heat resistance) it also has many disadvantages, including
low tensile strength as well as sensitivity to destructive action of chemical agents. A constant growth in expectations
concerning increasing the quality of concrete led to its polymer modification, whose aim was to
eliminate above-mentioned disadvantages. The scope of the present research involved designing and making
of concrete mixtures modified by 6, 12 and 19 mm long polypropylene fibres. For the experiment the authors
used: Portland cement CEM I 42.5R, sand, gravel aggregate of the 2–8 and 8–16 fractions, water, Master Pozzolith
STD plasticizer and polypropylene fibres of various length. The authors made three series of concrete
samples modified by fibres, for which the following factors have been assigned: compression strength after
7, 28 and 56 days of maturing as well as absorptivity, volumetric density and frost resistance after 100 cycles
of freezing and thawing. There was also conducted the flexural tensile-strength test after 28 days of maturing
of concrete samples of the particular series.