耐候钢桁桥焊接工艺评定及力学性能试验研究

Experimental research on welding procedure evaluation and mechanical property of weathering steel truss bridge

焊接工艺评定和力学性能试验是确定定制牌号耐候钢可焊性和焊接接头工作性能的有效途径。文章基于新建潍莱铁路潍莱右线跨青荣城际高铁特大桥(120+82) m连续钢桁梁工程,通过15组共计91个焊接接头的焊接工艺评定试验,研究了焊接接头耐候性匹配、单调拉伸、侧弯、低温冲击、硬度以及宏观金相组织等焊接接头性能。结果表明:试验中的焊材选择能够达到焊接接头耐候性的匹配,焊缝表面处耐候指数均值为6.70,焊缝表面耐腐蚀指数均大于耐候钢母材耐候指数标准值;焊接接头的各项力学和强度指标结果均具有一定的储备,宏观金相组织表明焊接成型良好。其研究结果可以作为新建耐候钢高铁桁梁桥焊接工艺的指导依据。

Welding procedure evaluation and mechanical property test are the effective ways to determine the weldability of customized weathering steel(WS).Based on the(120+82)m continuous WS steel truss girder on the newly-built Weilai high-speed railway project,with the welding procedure evaluation test of 91 welded joints in 15 groups completed,the welding joint properties such as weather resistance matching,monotonic tension,lateral bending,low-temperature impact,hardness and macro metallographic structure are studied.The test results show that the selection of welding materials in the test can achieve the matching of weather resistance,with the average weatherability index of the weld surface reaching 6.70.The corrosion resistance index of the welding surface is greater than the standard value of the weatherability index of the WS.The results of mechanics and strength of the weldments have a certain reserve,and the macro metallographic structure shows that the welding process meets the welding procedure evaluation standard.The research results can be used as the guidance for the welding procedure of the newly-built weathering steel high-speed railway truss bridge.