News & Information

Construction update

Posted on October 10th, 2017

Photo: Piling is underway at Illaweena Street, Stretton

A major construction milestone has been achieved on the Logan Enhancement Project, with the start of piling for the first of the 16 new bridge structures to be built as part of the project.

The piling is for the new Gateway Extension Motorway bridges over Illaweena Street, Stretton. Two new, three-lane bridges are being built, and these require a total of 33 piles, with the piles being bored to a depth of 12 metres.

Already three piles have been completed, which will be for the middle piers of the new northbound bridge. This new bridge forms part of the complex traffic staging, which when complete, will see traffic switched onto the new bridge and used by motorists while the existing bridges are demolished.

Once completed, the new bridges will accommodate the widening of the Gateway Extension Motorway from four to six lanes, as well as increasing the vertical clearance to eliminate the number of bridge strikes from trucks travelling along Illaweena Street.

Construction fast fact: What is piling?
Piles create a solid foundation to support a bridge by reaching a strong layer of soil or rock. There are different types of piling that may be used – bored, driven and continuous flight. Bored piling is underway for the new Gateway Extension Motorway bridges over Illaweena Street.

Bored piling is typically less noisy than driven piling, and involves a piling rig boring a hole in the ground. Depending on ground conditions, the piling may also require a steel liner to be installed into the ground prior to or during excavation. A prefabricated steel cage is lowered into the hole, with concrete then poured into the hole. Once the concrete has cured/set, the bored pile is complete.