Sanya River Estuary Passage Pipe-Roof

CRCHI supplied the Lucheng pipe-roofing machine for the subsea pipe-roof section of the Sanya River Estuary Passage, the world's first triple-circular pipe-roofing machine deployed on a triple-circular interlocking pipe-roof drive. The Lucheng achieved its first pipe-section breakthrough at 125.8 metres beneath the estuary, securing breakthrough accuracy within 10 mm under water pressures of up to 0.35 MPa and recording a peak single-shift advance of 6 metres through a mixed face of quartz sandstone, fault breccia and variable soils. The drive continues across the remaining pipe sections, with the wider crossing representing an investment of 550 million AUD and scheduled for completion in 2027.