Several influence factors for longitudinal residual stress of welded box column

Welded box column is main compression member of steel structure, and residual stress is the most important factor affecting the ultimate bearing capacity of box column. Based on ANSYS system, whole welding process is simulated by three dimension thermal elastic-plastic finite element method, element strain and node displacement solve by the node temperature change of established temperature interpolation function. There are more accurate results than parabola model or broken line model about residual stress. According to the simulation calculation result compare the effects on residual stress in these three aspects: height of column, sequence of welding, number of weld layer, provide some references for the practical engineering.