Statistical Comparison of the Results of Applying Several Methods in Checking Concrete Columns’ Fire Resistance

Abstract:

The main objective of this study is to help the structural designers so they can, quickly and efficiently, study the concrete columns’ fire resistance. The most expeditious methods of fire resistance verification in terms of ease of application by structural designers, the methods given in EN 1992-1-2 [1] in the form of tables (Method A, Method B and Method C), were used in the fire resistance verification of 12243 rectangular columns inserted in the stability projects of 63 buildings, carefully selected in order to be representative of the ones licensed in Portugal [2]. Noting that these methods lead to excessively conservative results, the authors developed an alternative methodology, also with expedite application, but leading to substantially less conservative results (although designed on the safety side). This methodology consists on the consultation of adimensional interaction diagrams in fire situation, N_fi/M_fi, developed using the 500oC Isotherm Method. In the development of these diagrams unexpected results were obtained in some columns’ cross-sections, for which the resistance at room temperature was lower than the one corresponding to a fire situation at level R60. Some of the factors that can contribute to the occurrence of these results are pointed out.

• Periodical: Key Engineering Materials (Volume 711)
• Pages: 572-579
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.711.572
• Online since: September 2016
• Authors: Maria Alzira Barros Ramalho*, Miguel Chichorro Gonçalves
• Keywords: Column, Concrete, Fire Resistance, Methods

References

[1] CEN, EN 1992-1-2: Eurocode 2: Design of concrete structures: Parte 1-2: General rules - Structural fire design. European Standard, December (2004).

[2] B.R. Maria, C.G. Miguel, Performance comparison between rectangular and circular cross-section columns in fire situation, using tabulated methods, 9th International Conference on Structures in Fire, US, 2016, pp.79-85.

[3] CEN, EN 1992-1-1: Eurocode 2: Design of concrete structures: Parte 1-1: General Rules and Rules for Buildings. European Standard, April (2002).