With the length of 5,664m, the submarine tunnel of Hong Kong-Zhuhai-Macao Bridge is composed of 33 giant immersed tubes and 1 joint. The tunnel is the largest highway immersed tunnel in the world and the only deeply buried immersed tunnel as well as the only immersed tunnel in Chinese open seas. In early 2013, the No. 2 Company of CCCC First Harbor Engineering Co., Ltd. started undertaking the installation task of immersed tunnel of Hong Kong-Zhuhai-Macao Bridge and is responsible for foundation construction, floating transfer installation and measurement etc. Afterwards, the company rapidly organized a craftsman team of “Qingdao Brand”.

    The immersed tube installation is a key procedure of the Hong Kong-Zhuhai-Macao Bridge and is the core part of “high-grade, precision and advanced” technologies. As the last giant immersed tube of the submarine tunnel and located on the east side of the tunnel closure, E30 immersed tube, 171m long, is a specially-shaped curve and looks like a trapezoid as a whole as well as the last strategic pass before guaranteeing the final installation of closure. Among 33 immersed tubes, the E30 tube is subject to the most limitations, the most difficult construction and highest precision. Therefore it can be called “set the tune with one beat of the gong -- give the final word”. It is said that in the process of installing 33 immersed tube for nearly 4 years, the No. 2 Company of CCCC First Harbor Engineering Co., Ltd., has constantly conducted scientific research and innovation, overcome difficulties, successfully developed and applied 8 safeguard systems of tube immersion, floating transfer and handling with the international leading level, has successively overcome many world-class difficulties including deep water and groove, strong back-silting and large run-off etc. as well as the technical problem of installing super giant curve immersed tubes. In 2015, the company created the “Speed of China” by installing 10 tubes within one year.

    On the same day when the E30 immersed tube was installed, the steel structure of final closure has arrived in Zhuhai after long distance transport from Shanghai Zhenhua Nantong Base. It will be grouted in Guishan immersed tube prefabrication factory and then the suitable window phase will be chosen and it will be hoisted with a 1,200 tons crane, the largest in the world. It is expected to conduct immersed installation this April and realize the connection of the Hong Kong-Zhuhai-Macao Bridge. Zhou Jianliang (The construction site of E30 installation site, the last giant immersed tube of the submarine tunnel of Hong Kong-Zhuhai-Macao Bridge. Taken by Xue Anping and Chen Litong)