Fatigue Performance Analysis of Welded T-Joints in Orthotropic Steel Bridge Decks with Ultrasonic Impact Treatment

Yizhou Liu; Wenhua Huang; Banhai Yu; Zhihao Chen; Ping Wang

doi:10.3390/ma16186196

Fatigue Performance Analysis of Welded T-Joints in Orthotropic Steel Bridge Decks with Ultrasonic Impact Treatment

Materials (Basel). 2023 Sep 13;16(18):6196. doi: 10.3390/ma16186196.

Authors

Yizhou Liu¹, Wenhua Huang², Banhai Yu², Zhihao Chen³, Ping Wang¹

Affiliations

¹ School of Ocean Engineering, Harbin Institute of Technology at Weihai, Weihai 264209, China.
² Wuhan 2nd Ship Design and Research Institute, Wuhan 430200, China.
³ School of Civil Engineering, Harbin Institute of Technology, Harbin 150001, China.

Abstract

This study aims to assess the effect of ultrasonic impact treatment (UIT) on the exterior weld seam of S355J2 T-joints used in orthotropic steel bridge decks. The microstructure and mechanical behavior of T-joints after UIT was investigated in this study. Fatigue tests of T-joints before and after UIT were performed. The stress concentration at the interior and exterior weld toe of T-joints was considered using the traction structural stress method. The results showed that hardness increases by 10% due to the localized grain refinement caused by UIT. UIT significantly improves the fatigue life of T-joint specimens by 350% and 150% at stress ratios of 0.1 and 0.3, respectively. As the transition angle between the weld profile and the base metal profile increases, the stress concentration factor decreases.

Keywords: T-joints; fatigue performance; grain refinement; stress concentration; traction structural stress; ultrasonic impact treatment (UIT).

Grants and funding

No. 2021NZ033016/Science and Technology Major Project of Fujian Province:Development of a novel high-performance platform for deep-sea fish farming and research of its key performances.