The Effect of Organic Lake Sediments (Sapropel) on the Properties and Biological Resistance of Unfired Clay Bricks

Abstract

Clay materials were prepared with clay and sapropel (SP) or clay and modified (frozen) sapropel (FSP) as the main raw materials. Clay-based materials were formed by mixing clay with a different dosage of SP or FSP (5–30 wt.%). The effect of SP or FSP on the properties and biological resistance of clay-based materials was studied. The results show that the bulk density of clay-based materials decreased, and the compressive strength and initial rate of water absorption increased with the increase in the SP or FSP amount in the clay mixture. Research has shown that SP or FSP can be added as a natural additive containing microfibers to improve the mechanical properties of clay materials. When clay bricks had less than 15% sapropel, dry or frozen, we tested the resistance impact of the fungi Rhodotorula mucilaginosa, Stachybotrys chartarum, Cladosporium cladosporioides, and Aureobasidium pullulans under normal conditions.