The work deals with the results of research on the influence of complex mineral additive: chemical water treatment sludge with burnt rock or fly ash or gaize. The rational content of chemical water treatment sludge in the complex additive was determined to be 50%. The relationship between compressive strength, flexural strength and W/C ratio, bettwen the flexural strength, E-modulus and the compressive strength were obtained. Complex mineral additive into fine grain concrete does not lead to a decrease in flexural strength and does not increase the E-modulus of fine grain concrete. The average range of the E-modulus of fine grain concrete with complex mineral additive practically coincide with those in Russian National Standart 56378 - 2015. The use of chemical water treatment sludge for fine grain concrete at amount of 20% of complex additive of a rateable composition instead of part of the cement provided to increasing of compressive strength at an equal W/C ratio relatively to the non-additive standard by 7 - 20%, and the flexural strength by 12 - 22% .
Keywords: miniral additive, tensile strength, modulus of elasticity, gaize, fly ash, burnt rock, chemical water treatment sludge
Expert work has been carried out to determine the causes of the low adhesion strength of hand-molded ceramic bricks with Maxpol colored masonry mortar. The tests were carried out in accordance with GOST 24992 on 6 series of samples aged 7 and 28 days of hardening. The adhesion strength in the series of tested samples at 7 days of age, which were washed with running water, is 54% higher compared to the samples that were not treated.The compressive strength of Maxpol colored masonry mortar meets the requirements of technical specifications 23.64.10-001-79211444-2017 . The adhesion strength in the masonry meets the requirements of technical specifications only in a series of hand-molded bricks that have been treated with running water at the age of 28 days.
Keywords: ceramic brick, colored masonry mortar, adhesion strength, compressive strength, separation area