Abstract
Abstract The bare steel structural members have a low fire resistance. However, in steel and concrete composite members, the concrete encasement, besides the contribution to the stiffness of the whole system, reduces the amount of heat that reaches the steel profile, increasing the its fire resistance. The aim of this paper is to conduct a numerical study on the behavior of steel and steel and concrete composite columns in fire, in order to compare their performance based on the variation of parameters such as the stiffness of the surrounding structure, geometric imperfection and load ratio. It has been found that, in general, the intensity of the geometric imperfection and stiffness of the surrounding structure does not affect the fire resistance of steel and composite columns. However, the stiffness of the surrounding structure raised the maximum value of the restraining forces generate throughout the heating. Regarding the load ratio, when increased, the fire resistance and critical temperature decreased.
Highlights
Steel and concrete are the main materials used in civil construction
The aim of this paper is to conduct a numerical study on the behavior of steel and steel and concrete composite columns in fire, in order to compare their performance based on the variation of parameters such as the stiffness of the surrounding structure, geometric imperfection and load ratio
The results indicate that, for high load ratios, sections with small dimensions present low fire resistance
Summary
Steel and concrete are the main materials used in civil construction. Regarding the fire action, steel has a poor behavior when not protected, since it has a high thermal conductivity and it forms profiles which parts have reduced thicknesses. From the restraining forces behavior, the author defined the concept of steel columns fire resistance as the moment when, after the internal forces increase, the column returns to the observed loading level prior to heating This moment is called critical time and the temperature associated with it is called the critical temperature. The following year, Correia et al [11] used the experimental data of the developed tests and carried out a numerical research with the purpose of proposing a simplified method to determine the fire resistance of steel columns in a fire situation with thermal deformation restrictions. Another phenomenon that helped in this decrease was the concrete displacement The following year, these authors [13] developed another numerical modelling, this time, in order to evaluate the influence of the applied load ratio on the composite column and the cross-section dimensions. The results indicate that, for high load ratios, sections with small dimensions present low fire resistance
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
