RESEARCH OF MECHANICAL PROPERTIES OF CEMENT STONE UNDER CONDITIONS OF TEMPERATURE GRADIENT
In the study below, the results of the mechanical properties of cement stone samples hardening under conditions of temperature gradients were obtained. The purpose of these studies was to experimentally study the effect of temperature gradients (T = +60- (-20) °C) on the mechanical properties of a hardening cement mortar with a water-cement ratio W / C = 0.26. As a result of the experiments, we can conclude that the temperature gradient has a significant effect on the hardening of cement samples. Strengthening of cement samples-cubes for different test points occurs with different intensity. We also note that an increase in the heating time to 8 hours gives a significant increase and subsequent accumulation of the strength characteristics of the samples, and with an increase in time to 10 hours, the maximum increase in strength is observed. There is also a tendency to nonmonotonic strength accumulation of some specimens. It is expected that with a further increase in the hardening time, the trend of non-monotonic hardening will manifest itself to a greater extent. It can be assumed that nonmonotonic hardening is due to the effects of heat and mass transfer. The study of these processes will help to better understand the degree of negative impact on concrete structures of the temperature gradient and subsequently develop measures to increase their service life.