Recently, the "Haiji II" ultra-deepwater pipeline frame, overseen by the Ocean Engineering Measurement Team of the School of Ocean and Civil Engineering at Shanghai Jiao Tong University, successfully completed its underwater monitoring project, obtaining valuable data on the entire installation process from towing and loading to sliding into the water. The operational sea area of "Haiji II" averages a water depth of approximately 324 meters, with a total height of the pipeline frame reaching 338.5 meters and a weight of 37,000 tons—nearly equivalent to the steel used in the National Stadium ("Bird's Nest"). This project posed challenges such as foundation settlement, large-scale lifting, control of weight and dimensions, shipping transportation, and installation. "Haiji II" is the largest pipeline frame in Asia in terms of height and operational water depth, designed to withstand severe sea conditions occurring once every hundred years.

In a first for Asia, "Haiji II" successfully elevated the platform application for pipeline frames to depths exceeding 300 meters, significantly reducing development investment, construction costs, and production costs. This accomplishment holds strategic significance in advancing China's offshore oil and gas exploration and production, safeguarding national energy security. In early November last year, the Shanghai Jiao Tong University Ocean Engineering team received the dynamic underwater monitoring task for "Haiji II," requiring simultaneous monitoring of the underwater movement process of the towing vessel "Ocean Oil 229" and the position, posture, structural stress at key locations, deformation, and operational environmental parameters of the "Haiji II" pipeline frame. This was necessary to collect critical data that would replicate the entire installation process from loading onto the ship, transportation, to sliding into the water. The Ocean Engineering Measurement Team has long been committed to monitoring large-scale marine operations such as the launching of pipeline frames and floating installations. Over the past decade, the team has conducted monitoring of the launching process for Asia's largest "Haiji I" (302 meters long), "Fanyu 34-1" (203 meters long), and the second largest "Liwan 3-1" (196 meters long) pipeline frames, obtaining valuable field-measured data that provides crucial support for the subsequent design of deepwater pipeline frames in China.

Compared to "Haiji I," "Haiji II" is larger in scale, presenting new challenges such as large-scale, cross-medium, and high-dynamic range monitoring. The team innovatively developed a self-contained distributed structure load trajectory acquisition warehouse and a pipeline frame installation monitoring system. This achieved comprehensive measurement of the entire installation process, including the deformation of the towing vessel, the posture of the pipeline frame and towing vessel, marine dynamic environmental parameters, and dynamic loads on key structures of the pipeline frame. Simultaneously, the monitoring system's sensor distribution spans the entire 338-meter length of the pipeline frame and encompasses measurements in both water and air medium environments. To ensure measurement stability, the team developed technologies such as multi-source information verification and remote communication diagnostics, ensuring the reliability of the monitoring plan and the credibility of the monitoring results. Currently, there are no public reports of international real-sea monitoring activities for pipeline frames operating at depths exceeding 300 meters. The successful implementation of this monitoring task makes it possible to develop a large number of potential marginal oil fields in deepwater areas, paving the way for economically effective exploitation of oil and gas resources in China's medium to deepwater offshore areas. As China's deepwater development progresses, these valuable field-measured data will undoubtedly provide the most solid data support for the innovative design, safe operation, and validation of design software for deeper pipeline frame platforms.