The article presents the results of studies of the rheological properties of liquid geocement composite materials for protection against electromagnetic fields. It has been established that an increase in the concentration of a mixture of functional iron-containing fillers from 15 to 60 wt. % in the speed range from 0.1 to 1 rpm contributes to an increase in dynamic viscosity values from 100,000 to 550,000 cP. It’s noted that with an increase in the spindle speed from 15 to 35 RPM, the values of dynamic viscosity lie in the range of 8860-3442 cP. With the same concentration changes, the plastic viscosity of the liquid composite material in the speed ranges from 10 to 25 rpm changes, respectively, to 1064.5 cP, 3096 cP, 25462 cP, which is 1.04, 3, 03 and 24.9 times exceeds the value of the plastic viscosity of the original geocement paint. It is shown that at low shear rates from 0.02 to 0.3 l/s and an increase in the concentration of the filler mixture from 0 to 60 wt. % shear forces increase sharply on average from 21.2 to 252 dynes/cm2. Increase in shear rate from 0.315 to 7.35 1/s. Shear forces gradually increase from 76 to 252 dynes/cm2. It is shown that when the content of a functional filler with a concentration of 15% liquid composite material can be applied to the substrate by pneumatic spraying; with a concentration of 30% - with a brush or roller; with a concentration of 45 to 60% using a spatula. The total shielding coefficients of the electromagnetic field of industrial frequency by layers of a mixture with a thickness of 0.22-0.25 mm with a shielding substance content of 15-60% (by weight) for geopolymer paint is up to 8.6; shielding coefficients of the electromagnetic field of microwave frequencies up to 7.9. In the presence of filler up to 60%, the reflection coefficient of the electromagnetic field of ultrahigh frequency does not exceed 0.34, while the reflection coefficient of ultramagnetic waves of ultrahigh frequency as estimated at 0.20, and the experimentally measured one is 0.22-0.23.

This article presents the results of determining the fire-retardant efficiency of heat-insulating granular plate based on geocement to protect metal structures from fire. According to the results of fire tests, it they found that with a plate thickness of 40 mm, the metal surface of an I-beam they heated to a critical temperature of 500 °C after 100 minutes of fire tests. This indicator provides the fire resistance class of metal structures P90 and the III group of fire retardant efficiency of metal structures. Based on the calculated data according to Eurocode 3, it they found that the critical heating temperature of an I-beam up to 538 °C with a plate thickness of 40 mm they achieved after 105 minutes of fire tests. This provides the fire resistance class of the steel column P90 and the III group of fire retardant efficiency. In order to ensure the fire resistance class P120, in the future, it is necessary to increase the thickness of the heat-insulating granular plate to 50 mm, which will allow transferring metal structures to the II group of fire retardant efficiency.

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