THE CHARACTER OF CHANGE OF PROPERTIES OF STEEL FIBRE CONCRETE AFTER TEMPERATURE EXPOSURE

Abstract

The article presents the results of an experimental study of the bending strength of steel-fiber-concrete (SFC) samples after exposure to high temperatures.The properties of SFC based on high-strength cement-sand matrix with reinforcement of five different types of fibers are considered.The percentage of the content of each type of fiber by volume ranged from 0.5 to 6.0%. All types of fibers had different strength and geometric characteristics.The research results showed that the tensile strength in bending of SFC specimens, in the range of exposure to temperatures from 20 to 1100 ° C, depends on the volume content of the fiber and its strength and geometric characteristics. Almost complete destruction of the SFC was observed at a temperature of 1100 ° C for all types of fiber under consideration and at all percentages of reinforcement. The residual strength at this temperature did not exceed 5 MPa.