Reinforcing preloaded steel I-beams by considering welding heat effects and geometric imperfections

This paper presents a finite element (FE) analysis based study on the behavior of preloaded steel I-beams reinforced with cover plates welded to the bottom flanges of I-beams considering welding procedure simulation. FE analysis is conducted to study the effects of welding heat, welding sequence and weld length on the behavior of steel I-beams reinforced while under load. It is observed that an appropriate welding sequence and weld length can reduce the residual lateral deformations induced from welding. Based on the analyses, a welding segment of L/9, where L is the length of the beam, is recommended for practical applications. Also, initial geometrical imperfection is found to affect the value and direction of the residual deformation resulting from welding. Furthermore, preloading does not have any significant effect on the behavior of the I-beam reinforced at a preload level up to 50% of the strength of the unreinforced beam.