Downer PipeTech has identified an exciting and innovative (patent protected) structural concrete lining system for renovating deteriorating and aging man entry pipelines, culverts and tunnels for water/wastewater, road and rail applications. Developed and widely used throughout the UK, the award winning Tunneline system is a simple in situ concrete lining technique utilising lightweight manhole accessible formwork and high strength pressure injected concrete.
ITS have recently entered into an exclusive long term relationship with the M3 Group (the technology owners) to develop the Tunneline system throughout Australia. The first contract to be completed using this technology for VicRoads has given the asset a new 100 year lease of life and has eliminated the risk to Australia’s most prominent highway from potential damage had the culvert not been repaired.
The system combines high strength concrete with steel reinforcement and specialist pumping technology together with an innovative bespoke formwork system. This results in the ability to install a pressure-placed compacted reinforced insitu concrete lining that can be designed to act as a stand-alone or composite liner in accordance with relevant Australian Standards.
Tunneline is a one pass operation and requires little or no pre works to stabilise the existing host condition. It is able to line all existing profiles and will also accommodate both vertical and horizontal bends as well as size and shape transitions within the existing hosts. It can be used to line all known culvert material types from 1200 to 9000mm. It can be designed as a standalone structure or as a composite form where some part of the existing host tunnel structure is taken into consideration in the final design. Not only can it be designed to withhold external loading from rail and road traffic under limit state conditions and also to AS5100 and AS2566 but can also be designed to accommodate internal pressures from sewers and water mains up to 12 Bar and as such are designed as water retaining structures. In larger diameter applications, having the option to choose a fully structural, rigid solution is an attractive proposition.
We have completed three projects to date as follows:
- VicRoads: The project involved the rehabilitation of a 100m long 2300mm id Corrugated Steel Plate culvert under the Hume Highway in Broadford VIC by installing a fully structural in situ concrete lining inside the host pipe to deliver a final diameter of 2000mm.
- Mid-Western Regional Council: rehabilitation of a 52m long 1800mm id PCC culvert under the Castlereagh Highway Ilford NSW by installing a fully structural in situ concrete lining inside the host pipe to deliver a final diameter of 1500mm.
- BHP Billiton Coal: rehabilitation of a 28m long 2400 x 2100mm Cast concrete Box Culvert under the Colliery Access Road Kemira Valley NSW by installing a fully structural in situ concrete lining inside the host structure to deliver a final section of 2100x1800mm together with integrated refurbishment to the upstream headwall