Research Advances on Effect of Cold-Forming and Residual Stresses in Cold-Formed Thick-Walled Steel

At present,there is no corresponding technical standard for plate thickness above 6mm of cold-formed steel in China.The calculation methods of strain hardening of cold-formed steel using AISI,AS/NZS,ER3 and Chinese GB 50018—2002 specifications and their theoretical basis were presented firstly,and then the calculated values from these standards were compared with test data of thick cold-formed steel.It was shown that these specifications are all relatively conservative,and the results from Chinese and European standards agree very well.As a result,the Chinese GB 50018—2002 specification can be used for calculating the effect of cold forming in thick-walled steel.Besides,due to the distribution of residual stresses in cold-formed steel are quite differently from hot-rolled steel,the cold-formed residual stresses were reviewed from experimental,theoretical and numerical aspect,which provides a basis for further study of cold-formed thick-walled steel members.Finally,the future research trend on effect of cold forming and residual stresses in cold-formed thick-walled steel was discussed combined with our national code.