Temperature field of concrete-filled steel tubular columns in fire

Abstract The composite structures formed by the association of steel profiles with concrete have shown to be an advantageous alternative, improving the behavior of the steel structures concerning their load capacity, stiffness, and durability, under fire conditions. The concrete-filled tubular columns have become an attractive alternative for the civil construction area, offering constructive and esthetic advantages. The Eurocode 4 (EN 1994-1-2, 2002) and ABNT NBR 14323:2013 show simple methods for the design of the composite columns under fire situations. Nevertheless, these present limitations in their application. In addition, regarding the determination of the temperature field in the cross section, the Eurocode 4 (EN 1994-1-2, 2002) describes a specific procedure for columns with section profile covered with concrete, but it is neglectful about concrete-filled tubular columns. The goal of this paper is to present a simplified procedure to determine the temperature registered in concrete-filled steel columns and apply the procedure to columns with square section tubes. The temperature distribution was determined by simulations using the computer package ABAQUS (Dessault Systemes Simulia Corp. 2013). After the studies, it has been considered that the procedure described in this paper is an effective alternative for the determination of the field's temperature and for the application of the design of the concrete-filled columns under fire conditions