PERRY BRIDGE, HOROTIU
The Te Awa River Ride walk and cycleway stretches along the Waikato River in central New Zealand. The Perry Bridge was the final link in the chain, completing the path and opening up a fantastic activity for locals and visitors to the region. Holmes and Emmetts Civil Construction submitted an alternative structural solution to the originally proposed timber suspension bridge, with a visually stunning, innovative network arch—installed using a unique cable launch method.
The efficiency of this form of structure kept its costs within a practical budget, while also presenting the local district council and Te Awa the opportunity to create a visually compelling focal point to help attract people to the cycleway. The optimised, intelligent design, features an extremely lightweight self-supporting bare steel frame. That allowed for an innovative and efficient construction sequence—launching the bridge across the river on cables. Our design also gave particular focus to protecting the long slender span against potential lateral vibration.
Some of the added damping solutions we developed, based on in depth dynamic analysis, included concreting the final sections of the steel tube that forms the arch (for mass damping), concreting the integral connection of the deck into the abutments to increase stiffness, and refining the deck cross section to tune the vibration response.
The opening of the bridge was a big community celebration, with music, performances, speeches, and over 1000 people attending. The project is considered a great success that has delivered much to the local communities. This project achieved a Silver Award in the ACENZ Innovate Awards 2018 and has been shortlisted in three categories in the prestigious IStructE Structural Awards 2018.
