Methodology for Calculating the Technical State of a Reinforced-Concrete Fragment in a Building Influenced by High Temperature

Abstract

The purpose of research was to develop a methodology for testing the fire-resistant quality of a building fragment influenced by a real fire to substantiate the main calculation methodology provisions and determine the residual load-carrying ability. While testing, it was supposed to determine the technical state of reinforced-concrete structures after high-temperature exposure and further intensive extinguishment. High-temperature heating and further fire extinguishing with water leads to the surface layers’ destruction and weakening of concrete. Impact on the structures of the open air leads to destruction and delamination of weakened concrete with further exposing of reinforcement and its corrosion. The approach, implemented in LIRA-SAPR software package, makes possible to take into account the influence of changes in the temperature regime of operation on the stress-strain state of the structure. After determining the temperature fields, it is necessary to reduce the rigidity characteristics of materials and perform a calculation of strength. When using this approach in order to determine the total deformations of the structure, it is necessary to take into account the creep deformation.