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Cavell Bridge is the second of two InQuik bridges constructed by Scenic Rim Regional Council using their own in-house construction crew.
The bridge replacement project was jointly funded by Council and the Australian Governmentunder the Bridges Renewal Programme Round Three.
Council entered into the Bridges Renewal Programme Round Three funding agreement with the Australian Government, for up to $557,150 (GST exclusive) for the Cavell Bridge replacement project, with Council’s contribution of $557,150 (GST exclusive) to be funded from Council’s Capital Bridge Replacement Program;
InQuik were engaged by Council to provide detailed design for the complete project including the detailed civil design of the road approaches and the piling design. SMEC – PDR was the design partner for this project.
Council work crews completed the construction of the project. Council subcontracted the
demolition of the existing timber bridge. Council work crews then constructed an earthworks pad at the central pier to the underside of the headstock to allow for piling and the installation of the pre-fabricated headstock. Piling works were completed by Councils subcontractor.
Council crews then installed both Magnelis-clad abutments which were 8.42m in length,
1.2m high to the underside of the deck and 900mm-wide with a 700mm stepped backwall and approach slab pocket; as well as the headstock. The SM1600-rated deck panels were installed simply supported over the abutments and headstocks using elastomeric bearing strips.
Each abutment came preassembled with 2 x wing walls, which are 1.9m-high and 1.8m-long and angled at 45 degrees to the abutment.
The abutments were backfilled and the approach concrete slabs constructed followed by the remaining approach road works and guardrail.
Key Project Points
- Initially the design was a single span 18m x 8.42m and was amended to 27.4m x 8.42m multi-span set with a 4% crossfall. The revised length and crossfall was introduced to facilitate a re-alignment of the bridge improving the horizontal geometry of Boyland Road. This design is a unique bridge for the InQuik System, however as the design changed InQuik were able to adapt and supply modular components to suit.
- Council work crews completed the construction of the project. Council subcontracted the demolition of the existing timber bridge and the piling works.
Challenges
- The project faced a number of challenges identifying the interfaces of design ownership between the civil design, the standard InQuik bridge elements and the overall structural design to cover flood loading, bridge joints and piling connections.
- The detailed site specific design identified that the standard InQuik bridge elements were inadequate to resist flood loading. Although the structural elements were adequate, the proposed upstands on the edges of the headstocks did not provide adequate resistance to the lateral loading from flooding. Furthermore, buoyancy checks identified that the bridge would be subject to uplift. The standard InQuik tie-downs were adequate to resist the uplift, however were not adequate to resist the lateral loading. This was resolved with the design of lateral restraint blocks.
