Fatigue Property and Improvement of a Rounded Welding Region between the Diaphragm Plate and Closed Rib of an Orthotropic Steel Bridge Deck

Abstract

By means of finite element modeling (FEM) and fatigue experiments, we study the fatigue performance of the rounded welding region between the diaphragm plate and closed rib of orthotropic steel bridge deck in this work. A local sub-model of the rounded welding region from the orthotropic steel bridge deck was developed to analyze the stress distributions. Based on the analysis results we designed the fatigue specimen for the fatigue test of this detailed structure. The fatigue experimental results revealed that the crack initiates from the weld toe of the rounded welding region and the stress concentration at the rounded welding region is the main mechanism of fatigue crack initiation. In addition, we propose three improvements to reduce the stress concentration of the rounded welding region, and the local structure optimization scheme of the diaphragm–rib weld can effectively improve the fatigue resistance of the detailed weld structure.

Built-Up Closed-Rib Steel Orthotropic Bridge Decks

“…They are needed to improve the load transfer and distribution, as well as reduce stress concentrations. Many recent studies have been conducted on identifying and reducing diaphragm fatigue problems [12][13][14]. This paper discusses classical orthotropic steel decks and introduces a new type of closed-rib section, i.e., a built-up section which represents a possible solution that minimizes the disadvantages of classical closed-rib decks.…”

Fatigue and Fracture of Traditional and Advanced Structural Alloys

“…High cycle fatigue is a traditional topic but still very challenging, as is well described in some of the present contributions. In particular, it becomes more and more critical if large scale effect occurs in the full-scale component also in civil construction and megastructures [1]. Aspects related to microstructure and interaction between fatigue properties and metallurgical properties are also very important for the fatigue design.…”