TY - JOUR

T1 - Interaction diagram based method for fire resistance design of eccentrically loaded concrete-filled steel tubular columns

AU - Albero, V.

AU - Espinós, A.

AU - Romero, M. L.

AU - Wang, Y. C.

AU - Renaud, C.

AU - Schaumann, P.

AU - Nigro, E.

N1 - Funding Information: The authors would like to express their sincere gratitude to the “Conselleria d′Educació, Investigació, Cultura i Esport” of the Valencian Community (Spain) for the help provided through project GV/2017/026. The authors also acknowledge the funding received from the European Committee for Standardization (CEN) for the Project Team SC4.T4 of CEN/TC250 , through the grant agreement CEN/2014-02 Mandate M/515 Phase 1. This unsatisfactory situation has led the European Committee for Standardization (CEN) to appoint a Project Team to develop a new simplified fire resistance design method for CFST columns. Prior to this Project Team’s activities, the authors of this paper completed the European RFCS funded research project entitled “Fire Resistance of Innovative and Slender Concrete Filled Tubular Composite Columns” (FRISCC) [14] . As a result of this project, a simplified method was developed. A key contribution of the simplified method is to assume that the effects of non-uniform temperature in the CFST cross-section can be represented by an equivalent uniform temperature for each of the different components (steel tube, concrete infill, reinforcement) of the CFST cross-section. Although the FRISCC project also proposed a calculation method for CFST columns under eccentric loading, the method was quite tedious to apply and was for single curvature only.

PY - 2018/9

Y1 - 2018/9

N2 - Previous investigations have highlighted that the current design method in Annex H of EN 1994-1-2 for the calculation of fire resistance of slender concrete-filled steel tubular (CFST) columns was unsafe, which led to the appointment of a Project Team (SC4.T4) by the European Committee for Standardization (CEN) to develop a new Annex H in EN1994-1-2 to replace the existing one. This paper presents the outcome of the Project Team, a new simplified fire design method for CFST columns, focusing in particular on eccentrically loaded columns for which there had been no systematic research. An extensive parametric study consisting of 5046 analysis cases has been carried out, covering all the practical ranges of application of CFST columns. The method accounts for minor and major axis eccentricities with large eccentricities up to e/D = 1. Different bending moment diagrams, ranging from single curvature to double curve bending, were considered. The proposed new design method is in line with the cold design method in EN1994-1-1 and achieves the criteria of acceptance for safe and accurate design of structures in fire which were set by the CEN/TC250 Horizontal Group Fire.

AB - Previous investigations have highlighted that the current design method in Annex H of EN 1994-1-2 for the calculation of fire resistance of slender concrete-filled steel tubular (CFST) columns was unsafe, which led to the appointment of a Project Team (SC4.T4) by the European Committee for Standardization (CEN) to develop a new Annex H in EN1994-1-2 to replace the existing one. This paper presents the outcome of the Project Team, a new simplified fire design method for CFST columns, focusing in particular on eccentrically loaded columns for which there had been no systematic research. An extensive parametric study consisting of 5046 analysis cases has been carried out, covering all the practical ranges of application of CFST columns. The method accounts for minor and major axis eccentricities with large eccentricities up to e/D = 1. Different bending moment diagrams, ranging from single curvature to double curve bending, were considered. The proposed new design method is in line with the cold design method in EN1994-1-1 and achieves the criteria of acceptance for safe and accurate design of structures in fire which were set by the CEN/TC250 Horizontal Group Fire.

KW - Concrete-filled steel tubular columns

KW - Eccentric load

KW - Eurocode 4

KW - Fire resistance

KW - Numerical analysis

KW - Parametric studies

KW - Simplified design method

UR - http://www.scopus.com/inward/record.url?scp=85049437145&partnerID=8YFLogxK

U2 - 10.1016/j.tws.2018.06.017

DO - 10.1016/j.tws.2018.06.017

M3 - Article

AN - SCOPUS:85049437145

VL - 130

SP - 641

EP - 651

JO - Thin-walled structures

JF - Thin-walled structures

SN - 0263-8231

ER -