Influence of Deck Butt Weld Seams on Fatigue Life of Steel Bridge Decks Pavement: Parameter Optimization.

The butt weld at the connection between orthotropic steel bridge decks (OSBDs) can potentially pose a hazard to the fatigue endurance of the steel bridge deck pavement. This study aims to optimize the parameters of the butt weld seam using finite element (FE) analysis. The optimized parameters will provide valuable guidance for the design of pavements with a focus on antifatigue properties. Initially, the dynamic modulus of the epoxy asphalt mixture (EAM) was determined through laboratory experimentation at various frequencies and temperatures. These material parameters were then used to compute the pavement's fatigue life. Additionally, a well-established FE model was employed to analyze the deformation and fatigue life of the pavement structure. The validity of the model was verified by the theoretical calculation results. Various factors were considered, including vehicle velocities, pavement temperatures, and weld seam misalignments as well as weld seam dimensions such as height and width. The analysis was conducted using a three-dimensional steel bridge model. The results showed that decreasing pavement temperature, weld seam height, and misalignment led to an increase in pavement fatigue life. Conversely, reducing the weld seam width resulted in a decrease in fatigue life. Furthermore, the study investigated the coupling effect of different weld seam heights and widths on the fatigue life of the pavement. Contour figures were used to establish the parameter relationship formula for weld seam height and width. These findings are significant for pavement and deck designers because they enhance the understanding of the sensitivity of weld seams as design variables affecting the fatigue characteristics of pavement structures. Moreover, special attention should be given to the impact of welding parameters on the fatigue design of steel bridge deck pavement under high-temperature conditions of pavement structures. [ABSTRACT FROM AUTHOR]