The machine has a diameter of 15.8m - equivalent to the height of a five-storey building. China Railway Engineering Equipment Group has developed the machine, which weighs about 4,800t tonnes and is 135m long.
It will start work in mid-May boring the 5km double-decked Chunfeng Tunnel, which is being built to relieve congestion as part of the city’s Go East strategy.
It will be Shenzhen’s first single-bore tunnel with a double-decked interior and will provide four lanes and two continuous emergency parking lanes.
The TBM will cross 11 fault zones of up to 431m wide and will negotiate a minimum curve radius of 750 meters, said the Shenzhen government. Settlement control will also be essential, as the tunnel goes underneath a residential area, the city’s Metro Line 9 and other urban buildings and public infrastructure.