Estimation of fire resistance of bending reinforced concrete elements based on concrete with disperse fibers

Abstract

The results of estimative calculations of bearing capacity, critical temperatures, and fire resistance ratings of reinforced concrete bending elements based on fiber concrete with disperse reinforcement of steel, basalt and synthetic fiber are presented. The calculations carried out on the example of a reinforced concrete rectangular beam both taking into account the percentage of reinforcement of each element and at a constant load corresponding to the condition of calculation adequacy showed that disperse reinforcement of a reinforced concrete bending element with steel, basalt and synthetic fiber increases its bearing capacity, but slightly affects critical temperature and fire resistance rating. Despite the fact that concrete with basalt fiber is the least sensitive to heat, concrete with steel and synthetic fibers turned out to be comparable in this indicator with ordinary concrete. The presented results of evaluative calculations allow predicting the use of bending reinforced concrete elements based on concrete with disperse fibers in conditions of increased fire hazard, depending on the percentage of reinforcement and on the workload.