MassBloc® walls support upgrade of Brisbane bush road

Six retaining walls of various sizes were constructed using the MassBloc® system, as support and erosion prevention on steep embankments alongside the new Gap Creek Road at Mt Coot-tha.

Mt Coot-tha Forest is  Brisbane’s largest natural area, with more than 1500 hectares of open eucalypt forest.  It is adjacent to Brisbane Forest Park, which adds a further 28,500 hectares of bushland that extends well into the suburbs.

Gap Creek Road is an important north-south link between the suburbs of The Gap and Kenmore Hills.  Traffic volume on the old road had been steadily increasing over recent years, to around 1750 vehicles a day, exceeding the road’s safe operational capacity.

The road was also dangerous and badly corrugated, dumping dust on the surrounding bushland during dry weather and creating traffic hazards and erosion during rain.

Brisbane City Council designed the upgrade as part of its Road Action Program.  Golding Contractors carried out the works.  The speed of construction of the stacked MassBloc® system helped Golding make up for wet weather delays experienced during the construction period.  Rocla also supplied precast concrete pipes and headwalls for roadside culverts.

The dry-stacked Rocla MassBloc® retaining wall system comprises large permeable concrete blocks that interlock to create a permanent retaining structure.  They can be rapidly deployed to counter erosion, land slippage and rock falls.  The system is widely used for cut and fill installations, embankment stabilisation, temporary highway slip stabilisation and as rock fall barriers.