Recently, the concrete casting of the final joint of Shenzhen-Zhongshan Link's subsea tunnel was completed, marking the end of the main structure casting and laying a solid foundation for the opening of the link.

The subsea tunnel of Shenzhen-Zhongshan Link is approximately 6.8 kilometers long and has eight lanes. It is composed of 32 immersed tubes and one final joint. The immersed tubes feature shell concrete structures, which offer strong load-bearing capacity, good crack resistance, durability, and minimal impact on the marine environment.

The prefabrication of the immersed tubes for the subsea tunnel was carried out by the Fourth Harbor Engineering, a subsidiary of CCCC. The company was also responsible for the prefabrication of the immersed tubes for the Hong Kong-Zhuhai-Macao Bridge's subsea tunnel. Each immersed tube is 165 meters long, 46 meters wide, and 10.6 meters high. Once cast, it can weigh up to 80,000 tons, with an area equivalent to one and a half soccer fields.

So, how were these massive structures efficiently transported? This was made possible by the world's largest intelligent bogie system developed by the Fourth Harbor Engineering.

The system is composed of 200 electric railroad bogies with hydraulic lifting table, each one functioning like a small ant. The entire "ant squad" can carry up to 160,000 tons. Moving an 80,000-ton immersed tube over a distance of 220 meters took just 3.5 hours.