2016年7月下第45卷第14期
DOI:10.7672/sgjs2016140001
施工技术
CONSTRUCTION TECHNOLOGY
某超高层巨型转换桁架焊接残余应力
数值模拟应用研究
郭彦林，志乾1，朱邵辉2，宫健2，吕黄兵2
（1.清华大学土木工程系，北京100084；2.中建钢构有限公司，广东深圳518040）
[摘要】焊接是钢结构制作和施工过程中最常用的连接技术之一。焊接残余应力会导致结构变形和刚度降低，影响结构安全和施工质量，采用数值模拟方法预测大型钢结构的焊接残余应力对确定焊接工艺以及设计强度校核均具有重要意义。采用串形热源模型，以天津高银117大厦巨型转换桁架为研究对象，研究了转换桁架斜腹杆焊接拼装顺序对转换桁架焊接接头残余应力和转换桁架结构整体焊接残余内力的影响，对确定实际焊接施工顺序和工艺起到了定量指导作用。
【关键词］钢结构；巨型转换桁架；焊接；残余应力；数值模拟
［中图分类号】TU758.11
【文献标识码］A
【文章编号】1002-8498（201614-0001-08
Numerical Application Research on the Welding Residual
Stress of a Super-tall Giant Transfer Truss
GuoYanlin',Huan Zhiqian',ZhuShaohui’,Gong Jian’,Lu Huangbing
(1. Department of Ciril Engineering, Tsinghua Uniwersity, Beijing 100084, China; 2. China Construction Steel Structure Co. , Ltd. , Shenzhen, Guangdong 518040, China)
Abstract: Welding is one of the most widely utilized techniques nowadays in the fabrication and installation of steel structures. However, residual stress caused by welding would reduce the structure stiffness and change its initiate structural distortions thus affecting the overall construction quality and structure safety. Therefore, it is very significant to predict residual stresses and thus residual distortions on large-scale steel structures by numerical simulations and experimental studies. The method based on chained heat resource is applied in the on-site assembling and welding process of the giant transfer truss in Tianjin Gaoyin 117 project. The results obtained help to determine the construction welding sequence
of the web members which significantly affects the welding residual stresses of the transfer truss Key words: steel structures; giant transfer truss; welding; residual stresses; simulation
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引言
焊接是钢结构成型的重要加工工艺。焊接时，
热量高度集中的瞬时热源输入结构局部，使材料产生不均匀变形和热状态塑性压缩，导致构件或结构内部在焊接后产生残余应力，削弱焊接接头周边强
度或可能影响材料的韧性和硬度，伴随变形、高温脆化和裂纹（见图1)的产生[1)。
焊接残余应力的评估一直是人们关注的热点。半个多世纪以来，大量的研究人员投身于焊接残余应力的相关研究。人们在一系列假设条件下，得到部分典型焊接接头焊接残余应力的解析解，随后
[作者简介］郭彦林，教授，博士生导师，E-mail：gyl@tsinghua.edu.cr［收稿日期］2016-06-02
图1焊接裂纹 Fig.1 Welding crack
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通过试验和生产过程中获得的结果对解析解参数进行修正，优化焊接残余应力和变形的数学表达式，用于设计和施工。学者们将长期获得的理论成果和实际工程经验总结成焊接手册，服务于实际生产。但是，随着设计越来越复杂，焊接手册往往无