弹性状态低匹配焊接接头弯曲等承载设计准则与设计方法

弹性状态以低匹配接头能够达到与母材“弯曲等承载能力”（EBLCC）为目标，对低匹配对接接头焊缝几何形状临界条件进行了理论分析，推导了低匹配接头满足弯曲等承载条件的最低余高以及最小熔宽，并给出了弹性状态低匹配弯曲等承载接头设计准则.分析了圆弧替代抛物线曲线的可行性，给出了适用于工程应用方便的三圆相切低匹配弯曲等承载接头设计方法，并进行了弯曲试验验证.结果表明，设计的三圆相切低匹配弯曲等承载接头能够达到与母材弯曲承载能力，满足弯曲等承载要求.文中给出的设计准则与设计方法可使低匹配接头按照母材的弯曲承载能力进行设计，为弹性状态低匹配接头弯曲承载能力设计提供重要的理论依据.

Design criteria and design method for under-matched EBLCC joint in elastic stage

In order to make bending load-carrying capacity (BLCC) of under-matched welded joint reach that of base metal, theoretical research on critical condition for under-matched joint to satisfy equal bending load-carrying capacity (EBLCC) condition are conducted in this paper. Minimum reinforcement and minimum weld width of under-matched EBLLC joint have been derived in the elastic stage. Design criteria of under-matched EBLLC joint are proposed in the elastic stage. The feasibility of arc replacing parabolic curve has been analyzed, design method of three-circle tangential EBLLC joint which is suitable for engineering application are given in elastic stage. Experiments verify has been carried out for under-matched EBLCC butt joints with three-circle tangential reinforcement. Experiment results show that BLCC of under-matched joints can reach that of base metal and all bending specimen meet the requirement of the EBLCC design. In this paper design criteria and design method can make under-matched joint can be designed direct in accordance with BLCC of base metal. All of these can provide an important theoretical basis for BLCC design of under-matched welded joint in elastic stage.