EXPERIMENTAL STUDY ON RESIDUAL STRESS OF Q235 STEEL WALLBOARD-Q460 HIGH STRENGTH STEEL COLUMN STRUCTURAL SYSTEM

The wallboard-column structural system on the side of box-type steel structures plays a main bearing role. The residual stress distribution of the high strength steel column supported by stressed skin wallboards is affected by the welding with wallboards, as a result, it is quite different from the welded H-section of an individually working member. In order to investigate the residual stress distribution of Q235 steel wallboard-Q460 high strength steel column structural systems, an experimental study was conducted using hole-drilling method, including six structural system specimens and two independent Q460 high strength steel welded H-section specimens. Based on the experiment results, the magnitude and shape of residual stress distribution over the entire section were obtained. The effects of the welding connection between wallboards and column, sectional dimensions and the interaction among component plates on residual stress distribution were analyzed. The self-equilibrium of residual stress occurring in each plate was examined. The welding between wallboards and column reduces the maximum tensile residual stress in the middle of the column rear flange to a certain extent, and reduces the distribution range of the compressive residual stress in rear flange, but has no obvious influence on the front flange and web. The tensile residual stress amplitude is not directly related to the sectional dimensions. The compressive residual stress amplitude decreases with the increase of the plate width-thickness ratio. There is an interaction between the residual stresses of the component plates. The residual stresses of front flange, web and rear flange-wallboards composite plate can be considered to satisfy self-equilibrium respectively. An accurate and reliable residual stress distribution mathematical model for Q235 steel wallboard-Q460 high strength steel column structural system was proposed, which lays a foundation for subsequent research on the stability of high strength steel columns supported by stressed wallboard skin.