Non-linear analysis of slender straight and curved girders under normal and thermal loads
Keywords:
Nonlinear analysis; Elevated temperature; Heating and cooling; Curved beams.Abstract
This paper deals with nonlinear analysis of slender steel I-girders as well as horizontally curved slender steel I-girders under normal conditions and elevated temperature conditions. Under normal conditions, the effects of temperature on the analysis were neglected and under elevated temperature conditions, the temperature varies gradually from 0°C to 800°C. Three different girders, one straight and two curved girders, were modelled using the ABAQUS software. Effect of slenderness ratio and radius (for horizontally curved girders) were studied for 30m long slender I-girders as well as 30m long slender horizontally curved I-girders under normal conditions and elevated temperature conditions. It was found that slenderness ratio affects the axial force in the straight girders but does not have any significant influence on mid-span deflections at elevated temperature. For horizontally curved girder, the effect of angle subtended by the whole girder at the centre (radius of curvature) does not seem to have any significance for gradually elevated temperature. When temperature reduces from 800°C (i.e. cooling) to 0°C, a significant reduction in mid-span deflection was observed for straight girders but no significant reduction in mid-span deflection of curved girders was found. Finally, it can be concluded that horizontally curved girders are badly affected by elevated temperature compared to straight girders.