TBM Dame Whina Cooper, which is 130 m length, has broken through 60 m on its journey towards the Karangahape station under construction that is 830 m far away from its Mt Eden starting point.
The conveyor system and the large “shoes” which are bolted to the lining and have the reaction and also the arms attached which lead to a full steel ring, are illustrated as the red rollers in the photo below.
These factors let the TBM to push against these arms and shoes thus pushing the TBM forward and will be eliminated once the TBM is far enough in so as to be able to rely on ground friction.
The reassembling and relaunching process of this TBM for digging the second tunnel, will be done, after reversing it to the Mt Eden as soon as it reaches the new mid-town Aotea station construction site at the end of the year.
Due to the efficiency of this TBM, that is 15 m per a day, the excavation process of each tunnel will long almost 9 months.
The construction process of the second mined tunnel, which is 20 m beneath the ground and it is tunnelling full time a day, has been commenced by the Link Alliance team in the construction site, while the TBM is driving towards the new Karangahape Station. The team have to dig 150m deep into the ground to build a cavern tunnel that will later link to the tunnel bored by the TBM.
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