Launching is one of the crucial operations during offshore installation of a mega deep-water jacket. Haiji-1 mega jacket successfully launched in South China Sea at a water depth of 283 meters on April 10, 2022. In this paper, a comparative study on field motion measurement and numerical simulation of Haiji-1 mega jacket launch process is presented. Field motion measurements are carried out using Global Navigation Satellite System (GNSS) and Inertial Navigation System (INS) placed on jacket and launching barge. The potential flow theory software MOSES is adopted to simulate the launch process and several calculation conditions are designed for data regression and sensitivity analysis. Fair well agreements on motion trends are achieved but some differences between measurements and simulations also occur. A detailed analysis of these differences is given and several proposals for jacket launch operations in the future are presented based on the analysis.
As human activity gradually moves into deep sea, more mega jacket type platforms are being used in offshore oil and gas development. Recently, Haiji-1 mega jacket successfully launched in South China Sea at a water depth of 283 meters on April 10, 2022. This mega jacket has a length of 302 meters, and it weighs over 30,000 MT which makes it the largest jacket in Asian hitherto. The T-shaped barge HYSY229 was selected to launch this mega jacket. An aerial view of Haiji-1 jacket launching moment is shown in Fig. 1.
In a jacket design, launching is one of the crucial operations during offshore installation of a mega deep-water jacket. Hence, it is critical to accurately predict the motion response of such launch systems (Hu et al., 2016). To better understand the motion response of the jacket and barge during launching, many efforts have been made in numerical simulation or model test. Hambro (1982) proposed a method to calculate the jacket motions by distinguishing the constraints of the systems twice. Bhattacharyya et al. (1985) presented a model test technique to simulate the jacket launch process. Honarvar et al. (2008) compared model test and numerical simulation of launch operation. However, both methods have their limitations. In order to obtain the behaviors of the launch system, it is necessary to perform field measurements and make a comparative study.
