Constructors from China Railway No.4 Engineering Group Co., Ltd. (CREC4) have made a successful first blast for its No 2 Bid in building the world’s largest submarine tunnel in Qingdao, Shandong Province.
The explosion was done by CREC4 Seventh Engineering Co., Ltd on December 14 for the Jiaozhou Bay Second Tunnel, which will be 17.38 kilometers long, marking a new milestone in China’s engineering construction.
The Jiaozhou Bay Second Tunnel, which will link the city’s main urban areas with its West Coast New District, will be constructed through drilling and blasting. As the world’s largest submarine tunnel in size, it is also a submarine tunnel in China that will witness the highest water pressure for the tunnel shields and deepest burial depth for blasts.
In order to effectively reduce the blast’s impact on roads as well as on the daily life of nearby people and enterprises, the CREC4 Project Management Department adopted a method of “digital detonator controlled blast.” Before the blast, the management department set up a special leading group to coordinate external relations, communicating with the local government, the local police department, and conducting house-by-house investigations in the local communities, to ensure them of the controlled blast safety.
During the blast, technically, the CREC4 employees safeguarded the explosives filling quality, reduced the unit consumption of explosives and controlled the blasting noise generated by blasted flying-rocks by covering the blasted area, thus preventing the flying rocks from harming the surrounding passengers and passing vehicles.
The Jiaozhou Bay Second Tunnel, as a key project in Qingdao during the 14th Five-Year Plan period (2021-25) and a major artery in its “six horizontal and nine vertical” transport corridors in the city proper, will help boost traffic on both banks of Jiaozhou Bay, bolster the integration in the Jiaozhou Bay rim regions and enhance the high-standard opening-up of Qingdao.