Design and Fabrication of Bridge Decks made from Extruded Aluminium
2020 年 58 巻 Supplement 号 p. 138s-144s
詳細
2020 年 58 巻 Supplement 号 p. 138s-144s
Aluminium is increasingly used to replace aging concrete, steel or wood bridge decks. Typically, aluminium decks are made from extrusions welded together using gas metal arc welding (GMAW) or friction-stir welding (FSW) techniques. This paper describes firstly the steps followed in the design of an extruded aluminium bridge deck to be supported on steel girders in highway application. The design is based on the requirements of the Canadian Highway Bridge Design Code (CHBDC). It is observed that the fatigue strength of the aluminium alloy controls the design. Accordingly, specially designed AA6005A-T61 extrusion profiles are proposed. They are optimised by exploiting the fatigue strengths in both the plain and welded areas. In the second part of the paper, a manufacturing and assembly strategy is presented. This strategy proposes a specific sequence of installation that may provide satisfactory fit and limit the effect of any geometric inaccuracies in the individual extrusions. In addition, by using the GMAW technique with multiple passes, it may be possible to reduce the effect of heat deformations, the amount of distortions and residual stresses, especially near the heat affected zones around the welds.
