MICROTUNELLING
DJ Mac Cormick Contractors undertake tunnelling for diameters from 150 mm to 2500 mm with its fleet of Iseki & Herrenknecht closed face tunnel boring machines.
DJ Mac Cormick Contractors complete 234 m drive for 800 mm reinforced concrete jacking pipe DJ Mac Cormick Contractors have achieved yet another shining success on one of its longest single drives for non-man entry to date.
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J Mac Cormick Contractors have undertaken one of longest single drives for an 800 mm diameter closed face slurry shield micro tunnelling project, with no man entry available for installing intermediate jacking stations or slurry pumps. The project was completed on behalf of the city of Swan, located in the eastern metropolitan region of Perth in Western Australia. The drive length for a main drain was 234 m and due to the high level of traffic, community use and business trading work was only able to be undertaken over the Monday to Friday traditional work week. Launch and receival shafts were constructed utilising Ground Support Systems (Aust) shoring and associated safety equipment, which included certified structural KPA ratings for all the shoring. Temp designs were certified by structural engineer & undertaken for thrust block, entrance wall and concrete pad. DJ Mac Cormick Contractors had previously undertaken the previous stage back in 2019. The works in this stage involved several high complexity traffic MGE plans staged to ensure continual flow traffic through locality in order to minimise disruption to businesses as well as the broader community and residents. Ground conditions ranged from stiff clay to running sand. Underground streams encountered throughout the project also meant working on river sands and river stone cobbles during the drive length. All works were undertaken within 20 mm tolerance over drive. Upon completion of the drive, various 82 TRENCHLESS AUSTRALASIA OCTOBER 2022
tie in works and open cut drainage excavations including the construction of drainage manholes and side entry pits were required. This included the construction and maintenance of connections to existing drainage structures.
CCTV inspection of all lines was also required for this stage of the project, with a quality insurance pack and drawings provided upon completion. DJ Mac Cormick Contractors undertake tunnelling for diameters from 150 mm to
DJ Mac Cormick Contractors launch its TBM through entrance wall.