Structural behavior of right-angle two-planar tubular TT-joints subjected to axial loadings at fire-induced elevated temperatures.

This paper aims to investigate the structural behavior of two-planar tubular TT-joints subjected to axial loading at fire induced elevated temperatures. A total number of 270 FE analyses were performed to investigate the effect of temperatures and dimensionless geometrical parameters (β , γ , and τ) parameters on the ultimate strength and initial stiffness. The joints were analyzed under axially compressive and tensile loads at five different temperatures (20 °C, 200 °C, 400 °C, 550 °C, and 700 °C). Up to now, there has not been any design equation available for determining the ultimate strength of two-planar tubular TT-joints at elevated temperature. Results of the parametric study were used to develop a set of design formulas, through nonlinear regression analyses, to calculate the ultimate strength of two-planar tubular TT-joints subjected to axial loading at elevated temperatures. • Static behavior of two-planar tubular TT-joints at fire-induced elevated temperatures was studied. • Effects of temperature and joint geometry on ultimate strength, failure modes, and initial stiffness were investigated. • Results of 270 steady-state FE analyses were used for the parametric investigation. • Parametric equations were developed to determine the ultimate strength of axially-loaded TT-joints at high temperatures. [ABSTRACT FROM AUTHOR]