Assessment of the Residual Strength of Reinforced Concrete Partitions after Thermal Exposure

Abstract

The paper presents the results of an experimental study of the residual strength of a reinforced concrete partition after thermal exposure using the rebound hammer method. Measurements were performed before and after fire exposure at 28 control points located at four height levels of the structure. It was established that, after heating, a localized zone of strength reduction forms within the front surface. The average strength of the slab before testing was 50.9 MPa, whereas within the localized zone after testing it was 44.0 MPa; the relative strength loss was 13.5 %. The patterns of spatial variation in concrete strength indicators along the height of the structure were clarified, and informative features for identifying the zone of maximum thermal exposure based on the field of minimum residual strength values were established.