摘要:钢结构焊接损伤即在焊接过程中由于大量的瞬时热量输入，焊后会产生部分焊接缺陷，这些焊接缺陷包括：残余应力、气孔、夹杂、咬边、裂纹等。焊接缺陷将给钢结构的整体受力性能、疲劳强度和稳定性带来不利影响，特别是在地震荷载、冲击荷载等动力荷载作用下影响较明显，使得钢结构的安全性有一定的降低。本文总结了钢结构在焊接过程中可能存在的焊接缺陷问题，专门针对焊接不饱和问题提出通过构件在不同焊接率情况下的动力特性试验来研究不饱和焊接对钢结构构件动力特性的影响，为了分析不同支座对试验结果的影响，对焊接率分别为17.3%、33.3%、40%、65.3%、70%、100%共五种不同焊接长度的钢梁进行模态分析，采集了部分模态数据，并与完全焊接的工字钢梁进行对比分析，得出了不同的焊接率对钢结构构件动力特性的影响结论，为钢结构的设计施工提供了理论和实验依据。

Abstract: Steel structure welding damage is a result of a large number of instantaneous heat input in the process of welding. Welding produces some welding defects including residual stress cracks, porosity, inclusions and bite edge. Weld defects bring adverse effect to the steel structure including overall mechanical properties, fatigue strength and stability, especially the seismic load and impact load under dynamic load effect, which reduces the security of the steel structure. The paper summarizes the possible welding steel structure in the process of welding defects, specifically for the welding problem of unsaturated by components in the different welding rate of dynamic characteristic test to study the dynamic characteristics of the unsaturated welding of steel structures. To analyze the impact of different support on the test results, it analyzes five different welding length of steel beams on the modal analysis with welding rates of 17.3%, 33.3%, 40%, 33.3%, 70%, 100%, collects modal data and compares different welding rates of steel structures.The influence of different welding rates on the dynamic charateristics of steel structures is analysed as the conclusion, which provides theoretical and experimental basis for the design and construction of steel structures.