STUDY OF FIRE THERMAL EFFECT ON A REINFORCED CONCRETE BEAM ACCORDING TO THE RESULTS OF EXPERIMENTAL TESTS

Abstract

The paper analyzes the thermal effect of fire on reinforced concrete beams based on their heating according to the standard fire temperature regime in a small-sized installation for the study of the thermal effect of fire on building structures. Based on the proposed method, a methodology was created that makes it possible to obtain data on temperature distributions on the surfaces of a beam fragment and in its cross-section. The course and results of the conducted fire test are described, and the adequacy and reproducibility of the experimental data are verified. The temperature distribution over the entire area of the fire furnace, the studied fragments, was analyzed and the obtained results were processed.

The possibility of creating a standard fire temperature regime in the fire furnace chamber has been verified.

According to the results of this work, it was established that there is a uniform temperature distribution on the heating surface of the small-sized fragment under study, the maximum temperature reached was 806℃, the maximum temperature inside the beam was 480 ̊С, it was observed in the last minute of the experiment and continued to increase linearly after leaving the plateau. The maximum temperature on the unheated surface was 159 ℃, and on the unheated surface of the rock beam was 84 ℃, observed in the last minute of the experiment and continued to increase linearly after leaving the plateau.

The adequacy of the experimental data was confirmed: the relative deviation did not exceed 8%, and the calculated adequacy criteria (Fisher, Student and Cochrane) were below the critical value.