On October 27-28, the First Council and Technical Committee Meeting of the China Railway International Tunnelling and Underground Space Research and Consulting Center and the Conference on High-Quality Development of Subsea Tunnels were held as scheduled. More than 80 renowned academicians and experts from the tunnel industry at home and abroad, including Lu Chunfang and Du Yanliang, gathered together to conduct technical discussions and exchanges, and jointly "diagnosed and prescribed remedies" for the technical challenges of the Qingdao Jiaozhou Bay Second Subsea Tunnel, the world's largest and longest subsea highway tunnel under construction.

The China Railway International Tunnelling Research Center is a newly established R&D institution in Sichuan, initiated by the China Railway Academy Co., Ltd., a central enterprise based in Sichuan. It has now gathered a brain trust of tunnel experts from China, Europe, the United States and other countries, conducting technical consulting and research to tackle key and difficult tunnel projects in China and around the world.

It is understood that the main line of the Qingdao Jiaozhou Bay Second Subsea Tunnel Project is 17.48 kilometers long, of which the tunnel section is 14.37 kilometers, with the deepest point 115 meters below sea level. It is the world's longest subsea tunnel and presents three world-class challenges: complex geological conditions, great subsea burial depth, and long tunnel distance with heavy traffic volume, with technical difficulty reaching world-class level.

How to achieve large-section drill-and-blast tunnel construction? How to solve the waterproofing and drainage problems of large-section subsea tunnel construction under high water pressure in sea areas? How to break through the concepts and technologies of intelligent construction and construction control for subsea tunnels... On the 28th, the attending academicians and experts focused on these engineering technical challenges, discussing and diagnosing aspects of the Jiaozhou Bay Second Subsea Tunnel construction such as tunnel construction safety assurance technology, key technologies for long-distance tunnel boring, and preparation technology for tunnel functional materials. They openly put forward a number of rationalization suggestions, pointed out successful experiences of similar projects at home and abroad, and from a professional perspective, prospectively assessed the research directions in the field of tunnel and underground space engineering.

"This time we have invited top tunnel experts from China and abroad to jointly offer advice for the high-quality construction of subsea tunnels," said Yan Jinxiu, President of the 16th International Tunnelling Association and Director of the China Railway International Tunnelling Research Center. At present, China has built multiple subsea tunnels, and subsea tunnel construction technology has been continuously upgraded. The China Railway Academy, the executing unit of the research center, has gathered internationally top expert resources in the field of tunnels and underground engineering, and established an expert team composed of academicians of the Chinese Academy of Sciences and Chinese Academy of Engineering, well-known domestic industry experts, and dozens of foreign academicians and experts. It carries out extensive cooperation with renowned research institutions and universities in dozens of countries such as the United Kingdom, Switzerland and Norway, jointly conducting research on cutting-edge tunnel technologies and tackling key and difficult technical challenges, as well as the introduction, digestion, absorption and re-innovation of internationally advanced scientific and technological achievements and technologies, boosting China's cutting-edge technologies in tunnels and underground engineering onto the world stage.