This research uses the Euler-Lagrange coupling method to simulate spudcan penetration on jack-up rigs. It analyzes soil deformation and spudcan bearing capacity variations with depth. A three dimension(3D) finite element model is created based on geological data and spudcan shape to study the spudcan-soil interaction. The model determines the minimum penetration depth and corresponding bearing capacity to ensure operational safety. The predicted penetration depths using the American petroleum Institution (API) and China University of Petroleum (CUP) theoretical models show errors within 10% compared to numerical simulation and on-site observations. This study provides valuable insights into the mechanics of spudcan penetration processes on jack-up platforms.
The jack-up platform is an important part of equipment which is widely used in offshore drilling oil development operations. Stonor, R. W. P. et al. (2004) resented general conclusions regarding the optimal approaches for handling units that have incurred damage(Stonor et al., 2004). Bienen, Britta et al.(2009)draw a conclusion is that jetting is efficient in facilitating spudcan extraction, as it reduces the required uplift load(Bienen et al., 2009). Dai et al. (2010) used the projected area method to analyze the possibility of punch-through for a domestic jack-up at a well site in Bohai Bay(Dai et al., 2010). Yin et al.(2018) proposed a method that successfully avoids punch-through accidents by considering lateral friction, preloading speed, soil backfill effect, and group effect of spudcans, resulting in higher predictive accuracy of spudcan penetration depth(Yin et al., 2018). Zheng et al. (2018) discussed the advantages and disadvantages of the summarized design approaches, in particular for typical soil profiles encountered in the offshore fields including sand-over-clay, stiff-soft-stiff clay, soft-stiff-soft clay, clay-sand-clay, and clay-sand-clay-strong layer(Zheng et al., 2018). Hossain et al.(2019) comparatived data between load-penetration profiles calculated using industry-standard Organization(ISO) guidelines, a recently proposed mechanism-based calculation method, and 3D large deformation finite element simulations provided valuable insights for practitioners to estimate the behavior of jack-ups in sand soil profiles on problematic clay(Hossain et al., 2019).Yin et al.(2020) proposed three novel schemes to prevent the punch-through from experiments(Yin et al., 2020). Gao et al.(2023) used the real-time monitoring values of Real-time Pile Displacement (RPD) on the top platform to predict the lateral slip distance of the piles(Gao et al., 2023). Yi, Myung-Su et al.(2023) performed parameter sensitivity analysis using different environmental parameters(Yi and Park, 2023). Numerous scholars and engineers have extensively investigated spudcan penetration in relation to jack-up rigs, but research on pile pulling is lacking. Despite the growing utilization of jack-up rigs in various offshore applications, several key areas still lack comprehensive understanding and research. The absence of engineering practices, reliable models, and high-quality data necessitates further in-depth research on jack-up rigs. Consequently, the predictive analysis of depth of penetration for jack-up rigs plays a critical role in ensuring the reliable and effective utilization of jack-up rigs in offshore drilling. This study employs the CUP model to conduct calculations based on actual soil data and the jack-up platforms.