Fire-resistant design of eccentrically compressed stainless steel columns with constraints

Abstract

Based on the test results of 7 specimens in fire, the numerical simulation analysis were performed on the fire-resistance performance of the eccentrically compressed stainless steel columns with constraints and the numerical simulation methods were verified. The parametric analysis was carried out to investigate the influence of key factors (such as load ratio, eccentricity, axial constraint stiffness ratio, slenderness ratio, and so on) on the fire-resistance of the eccentrically compressed stainless steel columns with constraints. Based on the existing fire-resistant design methods of unconstrained stainless steel columns, the calculation formula for the buckling temperature of eccentrically compressed stainless steel columns with constraints is proposed, and the relationship between the buckling temperature and failure temperature is obtained. The results show that the fitting formula can better predict the buckling temperature and the post-buckling stage may better improve the fire resistance performance of stainless steel columns. The load ratio, eccentricity and axial constraint stiffness ratio are the key factors that determine the fire-resistance performance of eccentrically compressed stainless steel columns with constraints. The greater the load ratio, eccentricity and axial constraint stiffness ratio, the greater the deviations between the buckling temperature and failure temperature become and the better the fire resistance performance of columns in post-buckling stage. When the slenderness ratio is among 80–120, the difference between the buckling temperature and failure temperature is the smallest, and correspondingly, the fire resistance performance of stainless steel column is weakest.