Post-fire buckling behavior of high strength steel box columns

This paper investigates the buckling behavior of high strength steel columns in different temperatures using Abaqus finite element software. Initially, a finite element model of a box section was validated with an experimental sample of a high strength steel section under compression loading. After the validation, ۱۰ finite element models are developed, which were subjected to compressive loading at ۱۰ different temperatures from ۲۰۰ to ۱۰۰۰ degree Celsius. The results show that at different temperatures, the first buckling mode was the dominant buckling failure mode in all columns, leading to a reduction in the column's ultimate bearing capacity before failure. In addition, at temperatures above ۵۰۰ degrees Celsius, the ultimate resistance capacity of the columns was significantly decreased. This value reaches approximately ۲۰% of the ultimate resistance of same section at the normal temperature. At all temperatures, the deflection due to buckling in the mid height of the column did not change significantly and was not affected by temperature changes.

کلیدواژه ها:

High-strength steel column ، overall buckling behavior ، post-fire temperature ، finite element parametric study ، ultimate strength