Petrie Creek Road Bridge
Located approximately six kilometres west of Maroochydore over Paynter Creek, the Petrie Creek Road Bridge (also known as Dusty Rhodes Bridge) provides an important regional link.
CMC was engaged to construct a new prestressed concrete bridge to replace the existing timber bridge which was over 50 years old and had significantly deteriorated with many timber piles requiring strengthening or replacement.
Works were undertaken within an environmentally sensitive tidal estuary subject to strict environmental constraints. Acid sulfate soils were also present and disturbance of the river banks and channel were not permitted.
CMC delivered a new 76 metre long, 13.6 metre wide, four-span transversely stressed precast prestressed deck unit bridge. The scope also included demolition of the existing bridge, realignment of the existing approaches, and realignment of the intersection with Diddillibah Road.
Petrie Creek Road was heavily trafficked (10,000 vehicles per day) throughout the works with limited room available at the abutments for construction.
The design level of the bridge resulted in the piles and headstocks being regularly inundated by tidal movements. CMC undertook a detailed planning review of construction methodologies and devised a strategy that included purpose built plant (falsework, piling equipment, and access equipment), works staging, and flexible work shifts to suit tidal movements.
The project demonstrates CMC’s ongoing success in bridge construction over water and capability to manage significant environmental, traffic and programming constraints.
HIGHLIGHTS & OUTCOMES
Construction innovations mitigated unexpected impacts to program including high rainfall, tides and latent ground conditions to achieve completion on time.
Proposed Controlled Modulus Columns in lieu of timber driven piles which delivered significant cost savings and achieved the client’s 100 year design life.
Innovative temporary steel bridge was used to construct the substructure and avoid creek disturbance.
Spoil from piling works was contained and treated within settlement bunds.
Extensive ground treatment of soft soils.
Worked under live traffic conditions – 10,000 vehicles per day.
Detailed staging and traffic management plans maintained traffic flows and delivered program efficiencies.