frost resistance.

PROPERTIES OF MONOLITHIC CEMENT CONCRETE, HARDENING AT TEMPERATURES CLOSE TO ZERO

One of the main problems of hardening monolithic cement concrete, especially in the conditions of restoration and reconstruction of various objects, is the hardening of concrete in conditions of negative temperatures. Winter concreting technologies are divided into two main methods: the thermos method, in which the temperature of the environment in which the concrete hardens, must be above zero degrees Celsius, or the use of antifreeze additives.

Покращення експлуатаційних властивостей керамічної цегли поверхневим модифікуванням поверхні

In the article there are substantiated and determine the optimal composition of protective covering by the mathematical planning method with taking into account the influence of protective covering on water absorption, adhesive strength and frost resistance. It is constituted technologic regime of marking and hardening protective covering on the ceramic matrix surface. It is determined the depth of protective covering penetration and its role in the adhesive contact formation during hardening process and its dependence from ceramic matrix structure.