A sneak peek into the Shenzhen-Zhongshan Link

The Shenzhen-Zhongshan Link, a mega cross-sea highway connecting the southern Chinese cities of Shenzhen, Zhongshan and Guangzhou, will begin pilot operation on Sunday.

The core transportation hub project in the Guangdong-Hong Kong-Macao Greater Bay Area will shorten the travel time from Zhongshan to Shenzhen from the current two hours to 30 minutes.

With a total length of 24 kilometers, the link consists of one undersea tunnel, two cross-sea bridges and two artificial islands, making it one of the most challenging cross-sea cluster projects in the world.

The link's undersea tunnel, which is 6.8 kilometers long, has a central pipe gallery that integrates facilities for power supply, water supply and drainage, firefighting, communication, and intelligent control, and serves as an emergency exit.

The 5-kilometer-long central pipe gallery is laid with hundreds of cables and pipes of various kinds, with over 10,000 sets of equipment installed.

The tunnel is equipped with a large number of intelligent devices to ensure its safe and stable operation, including 14 robots, dual-wavelength flame detectors and Beidou satellite navigation signal simulators.

The robots regularly patrol along prescribed routes in the emergency exit and cable channel to monitor the operation of equipment and the environment in the pipe gallery.

They can also direct traffic with built-in loudspeakers in cases of car accidents while also filming the scene and transmitting the image to the remote control center in a real-time manner.

"We are the first to invent a horizontal smoke exhaust pipe system at the top of the immersed tube undersea tunnel, which improves the smoke exhaust efficiency by 42 percent. We have also established a new firefighting and smoke exhaust technology system for ultra-wide and interchangeable undersea tunnels, effectively ensuring safe fire evacuations," said Ma Ershun, deputy director of the link's management center.

The tunnel is flanked with lights that can change color based on temperature and traffic conditions. In emergencies, the light strips would be red, yellow and green from near to far to guide the evacuation.

The tunnel is also equipped with intelligent lighting control devices that can automatically adjust light brightness to levels that are safe and comfortable.