Acta Scientiarum Polonorum

The paper presents the results of the research on selected physical and mechanical properties of the clay
composite with the addition of straw and quartz sand. The clay content in the tested samples ranged between
63% and 53%, straw 5–13%, sand 4–10%. The tests of contraction, density, bending strength and compressive
strength of clay composite samples were carried out. The obtained results indicate the positive impact
of additives on the tested properties. Along with the increase in the content of straw and quartz sand, the
contraction of the drying decreased, the compressive and bending strength increased. The best results were
obtained for samples containing 58% of clay, 9% of straw, 6% of sand, and 27% of water. The obtained test
results indicate the suitability of the examined composite as a material for erecting load-bearing structures
of buildings.