DETAILED SCOPE AND DESCRIPTION

This project featured the replacement of an existing timbertopped bridge with a new concrete bridge on a new alignment. Located approximately 15 minutes south of Mundubbera in the North Burnett Region, the existing John Peterson bridge, a 100- year-old, 5.8m wide single-lane, timber bridge frequently overtopped during floods with an ARI of 2 years (50% AEP).

During the 2011 flood event, the bridge was closed for approximately 21 days. Up to 10 accidents were reported in the vicinity of the bridge in the ten years prior to the replacement of the bridge.

The timber bridge has now been replaced with a stronger and wider concrete bridge to improve safety and freight efficiency. As a result of the upgrades, the maintenance costs over the service life of the bridge are expected to be reduced.

The new John Peterson Bridge is significantly higher than the existing bridge, with up to 15m high columns, reducing the likelihood of closures on the Mundubbera-Durong Road during flood events. On average, 465 vehicles use this section of the road daily, with more than 24 per cent of those being heavy vehicles. The expected annual traffic growth is 9%.

The new bridge from approximate chainage 13.52-13.68km features eight 20m spans for a total of 160m. The concrete bridge features driven steel liners and cast in place piles, headstocks, abutments and piers, prestressed concrete deck and kerb units, bridge barrier and an asphalt DWS.

The associated road and civil works for the realignment to the new bridge approaches between chainages 11.18-14.50km included significant drainage, bulk earthworks, unbound pavement construction, road furniture including signage and guardrail installation, landscaping and revegetation, sprayed bituminous sealing and line-marking.

PROJECT OUTCOMES

The project objectives included the following:

• Delivering transport infrastructure that supports economic growth and provides access to services for the community
• Provide a safe, cost-effective and more dependable transport system