Experimental Study of Fatigue Durability in Bending Effect on Welded Joints in Steel Profiles

Ships are always prone to fatigue through high periodic loads, usually caused by waves and changing load conditions. So, fatigue is an important factor in design. One of the reasons for fatigue in welding parts is variable bending loads. In this paper, a specimen of low-carbon steel T-Bar profiles is used, along with plates of the same type of steel that have been welded by the manual electrode welding process. To determine the distribution of static and dynamic forces created by welding, the specimens were subjected to bending (three-point loading) and tensile tests, and finally fatigue tests. The T-Bar Steel profile has more tolerance for fatigue loads than welded. The load T-Bar profile has not failed until the two million cycles, while the welding specimen has failed in about 3×105 cycles. Finally, strong penetrating welds should be used if a stronger welding joint is required.