Bridges

Cover of Kaituna River Bridge Case Study
Kaituna River Bridge Case Study
  • Publication no: ABC-DES603-14
  • Published: 22 October 2014
The Kaituna River Bridge is a 187 m long, 27 m wide, four-span continuous composite steel-concrete bridge constructed as part of the Tauranga Eastern Link project in New Zealand. This paper discusses the design development of the bridge through to the final design, the design efficiencies, and the design challenges involved to produce a robust and practical design solution, as well as covering the construction methodology.During the tender design and option development phase of the bridge design, various options were considered and a steel girder bridge was the most favourable and economic option. This was mainly due to the poor ground conditions and physical constraints of the local road and the Kaituna River.The seismicity within the Tauranga area coupled with poor ground conditions meant the soil was subject to liquefaction in the 1 in 2500-year design seismic event. This required a robust design solution, with the bridge being supported on deep piles down to 50 m below ground level to mitigate the effects of liquefaction-induced ground displacements on the bridge. Design of the superstructure to satisfy the recommended fatigue loading added with the fatigue effects due to 40 t articulated dump trucks, in use during construction, posed design challenges. Benefits of the corrosion protection system for the structural steelwork were taken advantage of with the friction grip bolted connections, and the structural steelwork design was optimised to reduce the weight on the substructure.