Effect of copula-based models on structural response of jacket platform under wave stochasticity

Accurate estimation of structural response under stochastic marine loading is essential for ensuring the safety and durability of offshore jacket platforms. Conventional approaches often assume independence among environmental parameters, leading to oversimplified load estimations. This study introduces a copula-based probabilistic framework to capture nonlinear dependencies among ocean parameters and quantify their influence on the structural performance of jacket platforms. Both symmetric and asymmetric copula families are employed to develop joint probability models for wind, wave, and current characteristics, enabling a more realistic representation of oceanic load interactions. The proposed methodology is applied to a jacket platform located in the Mumbai High Basin, where statistical dependence among metocean variables is evaluated through correlation metrics and copula parameter estimation. The structural response is subsequently analyzed through finite element simulations under stochastic wave loading conditions. Results reveal that incorporating copula-based dependence modeling yields higher and more accurate estimates of base shear and overturning moment compared to conventional independent models. The findings underscore the significance of dependence modeling in offshore structural reliability assessment and demonstrate the potential of copula functions as a robust tool for realistic environmental load characterization and design optimization.