Experimental research on butt-welding deformation of thick plates in large steel structure

In reference to the current status that the existing experience formulae at home and abroad to predict butt-welding deformation of steel plates were inapplicable to the thick plates in large steel structure, the butt-welding deformation tests with full-scale thick plate models were conducted during the fabrication process of the steel towers of Nanjing No. 3 Yangtze River Bridge. The results indicate that the groove dimensions must be optimized and the rational welding sequence must be adopted, namely, the large groove side should be welded at first for the non-symmetrical X-type groove, and the proper angular distortion must be pre-setup according to different plate thickness for decreasing the welding deformation influenced by the deadweight of steel plates. For the butt-welding of thick plates, the transverse deformation will increase linearly and the longitudinal deformation which is proportional to the weld area will decrease and the angular distortion will decrease exponentially with the increase of steel plate thickness. The experience formulae to predict the transverse deformation and the longitudinal deformation and the angular distortion of thick plates butt-welding are induced through the test results.