Thermal stress state of reinforced concrete floor slab

Authors

DOI:

https://doi.org/10.32347/2410-2547.2019.103.43-56

Keywords:

finite elements methods, structures, thermal stress state, numerical experiments, thermal conductivity, comparisons

Abstract

The article provides research of the stress-strain state of a reinforced concrete floor slab under fire conditions according to refined method. The finite element model of the slab is created. At the first stage of the research, one solved the unsteady heat conduction problem. According to the solution of the problem, it is possible to obtain the temperature fields all over the section of the considered structural element at certain intervals of time. The second stage of the study is strength analysis. Due to the strength evaluation, it is possible to investigate the work of the floor slab at different time points of fire exposure. Several mathematical models are considered. These models correspond to different points in time of fire impact. In each design model of the floor slab, the strength and deformation characteristics of concrete and reinforcement were deepen in accordance with the section temperature. It made three types of fire resistance analysis of the structure: linear analysis, physically-nonlinear analysis, and physically-nonlinear analysis with taking into account the effect of creep. The results of comparison of the kinetic performance of the mathematical models in various problem statements are showed. The technique, which allows to take into account the influence of creep in the numerical simulation of fire effect is proposed.

Author Biographies

Mariia Barabash, National Aviation University

Doctor of Technical Sciences, Associate Professor, Senior Researcher, Professor, Department of Computer Technologies, Building, NAU Airport Scientific Research Institute

Maryna Romashkina, LIRA-CAD LLC

Candidate of Engineering, Design Engineer

Olga Bashynska, National Aviation University

Assistant Professor, Computer Engineering Department

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2019-10-01

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