聂春戈 魏宏迪 管明珠 李博

摘要：针对Eurocode 3标准提供的角焊缝计算公式难以直接用于工程结构中非熔透焊缝静力强度评估的问题，分析网格不敏感结构应力法中结构应力的3个膜应力分量与Eurocode 3标准中的3个焊缝应力，发现两者高度一致。基于此，提出基于结构应力的非熔透焊缝静力强度评估方法，并对驮背运输车油缸支座关键焊缝的薄弱截面进行结构应力计算，结果表明：焊缝长度方向的应力分布复杂;以焊缝最大组合应力接近许用应力为判据估算得到导向轮的极限载荷约为30 t。研究结果可为准确评估焊接接头的安全性提供理论依据。

关键词：

非熔透焊缝; 结构应力; 静力强度; 焊接接头; 承载力

中图分类号：TG407; TP391.92

文献标志码：B

Static strength evaluation method for non-penetration weld

based on structural stress and Eurocode 3 standard

NIE Chunge， WEI Hongdi， GUAN Mingzhu， LI Bo

（School of Locomotive & Rolling Stock Engineering， Dalian Jiaotong University， Dalian 116028， Liaoning， China）

Abstract：

As to the issue that the calculation formulas of the fillet weld provided by Eurocode 3 standard are difficult to be directly used to evaluate the static strength of non-penetration welds in engineering structures， the three membrane stress components of the structural stress in the mesh insensitive structural stress method and the three weld stresses in the Eurocode 3 standard are analyzed， and it is found that they are highly consistent. Based on this finding， the static strength evaluationmethod for non-penetration welds based on the structural stress is proposed， and the structural stresson the weak section of the oil cylinder support key welds of the piggyback transport vehicle is calculated. The results show that the stress distribution in the weld longitudinal direction is complex. Based on the criterion that the weldmaximum combined stress can approach the allowable stress， the ultimate load of the guide wheel is estimated to be about 30 t. The research results can provide a theoretical basis for the accurate evaluation on the safety of welded joints.

Key words：

non-penetration weld; structural stress; static strength; welded joint; bearing capacity

0 引 言

熔透焊接接頭的强度一般能够接近或达到母材强度，非熔透焊接接头往往应力状态复杂、强度较低。工程设计历来十分重视结构强度。[1-2]常规工程结构中存在大量非熔透焊接接头，如角焊缝接头、单侧对接接头、厚板接头等，如果焊缝尺寸不足，那么接头极限承载能力将远低于母材，进而影响整体结构的安全性。因此，在接头设计和结构强度评估时应重点关注非熔透焊缝。

针对非熔透焊接接头的强度评估，文献[3]中有简单的计算公式，而工程中应用更多的是基于接头尺寸的焊缝强度详细评估方法，其中比较典型的是Eurocode 3标准[4]中的角焊缝强度评估公式，即

σ2⊥+3（τ2⊥+τ2∥）≤fuβγ

σ⊥≤fuγ

（1）

式中：fu为接头连接薄弱部分母材的名义拉伸强度;β为与钢材种类对应的相关因子;γ为分项因数，一般取γ=1.25;σ⊥为焊缝最小截面上的法向应力;τ⊥和τ∥分别为截面上垂直和平行方向的剪切应力。……