RESISTANCE OF FIBER-REINFORCED CONCRETE TO HIGH-TEMPERATURES

Abstract

The article presents the results of a study of changes in the structure and properties of concrete reinforced with low-modulus synthetic microfibres after exposure to high temperatures. The analysis of the causes of the phenomenon of explosive destruction in concrete during heating is carried out. A review of modern methods of increasing the fire resistance of building structures, including possible ways to prevent their explosive destruction in the event of a fire, is performed. It is shown that synthetic microfiber burns out at a temperature close to 400 ° C, forming additional porosity for water to escape in the form of steam from concrete. With a further increase in temperature to 600 ° C, a significant number of cracks are formed that increases the defectiveness of the structure and reduces the strength of fiber concrete. Comparison of the water resistance of concrete and fiber-reinforced concrete samples after temperature exposure by the filtration coefficient is carried out. The mechanism of increasing the resistance of concrete to high temperatures and explosive destruction upon heating as a result of reinforcing with low-modulus microfibers has been clarified.