Recently, with the last "big barrel" arrived at the designated position and sunk into place, all 30 new barrel infrastructure structures of the Xiaoyangshan North Operation Area Working Boat Wharf Project undertaken by CCCC Third Harbor Bureau were sunk and completed, which is the 30th and last installation of the first barrel infrastructure of the Xiaoyangshan North Operation Area Work Boat Wharf Project since July 15, 2023, marking the completion of the installation of the "Big Round Barrel" infrastructure of the Xiaoyangshan North Working Boat Wharf.
The Xiaoyangshan North Operation Area plans to build 7 70,000-ton and 15 20,000-ton container berths, and simultaneously implement related supporting projects, with a designed annual throughput capacity of 11.6 million TEUs. The construction content of the wharf is 618.3 meters in length of the wharf shoreline, and the wharf has the function of wave and wave protection after completion, which can be used for the berthing operations of auxiliary ships such as maritime, pilotage, tugboat, ship sewage collection ship and so on.
Considering that the construction area is the offshore sea area on the north side of Xiaoyangshan and the hydrometeorological conditions are harsh, in order to ensure that the substructure of the wharf is more stable and minimize the pollution of the construction area, the project team innovatively used the combination of barrel foundation and sand pile composite foundation to construct a new wharf structure that can be used in soft soil foundation. Compared with the traditional gravity wharf, the use of prefabricated barrel basic structure with a dead weight of up to 5,000 tons as the substructure can better resist the waves with high cross-current velocity, and there is no rubble foundation bed in the process, the process is clearer and more environmentally friendly.
The first in China means that the project construction team will face a new construction technology and blank construction data. The General Manager Department of the Xiaoyangshan North Operation Area Project of the Third Harbor Bureau has set up the transportation and installation of the new barrel infrastructure as a special scientific research topic, and has carried out sufficient theoretical and simulation research before the construction of the project. The technical team of the project fully combined the characteristics of engineering and environment, carried out a 1:10 model test in the Kangqiao Test Base of the Key Laboratory of Engineering Structure of CCCG, and finally determined to adopt the negative pressure barrel structure form without bottom and cover as the barrel basic structure. The substructure of the wharf is arranged by 30 barrel basic structures, a single barrel body is composed of two structures, the lower barrel is a bottomless thin-walled structure, and the upper barrel is a rectangular caisson structure, with a maximum barrel length of 40 meters, a width of 20 meters, a height of 26.5 meters, and a weight of 5,492 tons.
In order to ensure the progress of the prefabrication of the barrel infrastructure and create relatively smooth transportation conditions, the Third Harbor Bureau has developed a "tailor-made" Dayangshan Offshore Engineering Base for the development of the Xiaoyangshan North Operation Area, which is used as the prefabricated base of the barrel infrastructure to bring convenience to the subsequent transportation and installation. During the construction process, the project team has always implemented the concept of "high-quality engineering and green engineering", and cooperated with the measurement and positioning system and the bucket infrastructure subsidence control system developed by the Technology Center of the Third Harbor Bureau, which can remotely control the operating platform within 5 kilometers and monitor the installation position and elevation changes of the barrel infrastructure in real time. In the process of sinking, exhaust, drainage and other construction processes, there is no need for large ships to vibrate and sink in the whole process, and there is no noise in construction, less energy consumption and no environmental pollution.
According to the maritime department, the construction water area is in the open sea, the hydrometeorological conditions are poor, the barrel infrastructure is affected by the cross-current in the process of towing and sinking, which is prone to deviation and tilt, and the risk of towing operation is high, and the construction is difficult, which puts forward higher requirements for safety supervision. Since the start of the project, the Yangshan Port Maritime Safety Bureau has continued to strengthen on-site supervision and service guarantee, through the combination of remote monitoring of the ship traffic management center and on-site escort of maritime patrol boats, to achieve all-weather, full-time and all-round safety supervision, organized and held construction safety coordination meetings for many times, implemented ship inspections and supervised the rectification of safety defects, sent personnel to regularly visit the project department to carry out safety knowledge lectures and on-site emergency drills, and continued to deepen information exchange, law enforcement linkage and resource sharing with water-related units.
At present, the backfill in the barrel and the construction of the superstructure are being carried out in an orderly manner after the installation of the barrel basic structure is completed. According to Liu Haiqing, general manager of the general manager department of the Xiaoyangshan North Operation Area project, the project technical team will further collect and analyze the data of the barrel infrastructure construction process, continuously optimize and refine the process flow, and lay a solid foundation for the construction of the barrel foundation structure of the breakwater and shore connection structure project in the Xiaoyangshan North Operation Area in the later stage.
Xiaoyangshan North Operation Area is an important part of the Yangshan International Container Hub Port Area of Shanghai International Shipping Center, and is also an important supplement to the trunk container terminal of Xiaoyangshan Operation Area. The construction of Xiaoyangshan North Operation Area is a major measure to promote the higher-quality integrated development of the Yangtze River Delta, and plays an important leading role in further deepening the construction of Shanghai International Shipping Center and expanding a higher level of opening up.
Text: Li Jicheng, Yang Zhenying, Zhou Yanwen, Feng Yanghong
Editor: Wang Yumeng
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