Modeling and Optimization of Lashing Systems for Large Cargo Under Tipping Conditions in Maritime Transport

Background : Current international regulations for cargo securing rely on simplified assumptions that may not accurately represent the behavior of oversized cargo, particularly regarding rotational inertia and ship motion effects, which are critical under tipping conditions. Methods : This study presents a methodology for the evaluation, modeling and optimization of lashing systems for large cargo units. A comparative analysis between the CSS Code and DNV guidelines is performed to assess differences in the estimation of ship-induced accelerations and the resulting tipping moments. Simulations are performed considering different stowage positions, environmental conditions, and lashing configurations. Predictive mathematical models are developed using Design of Experiments (DOE) and Response Surface Methodology (RSM). Results : The results reveal that the CSS Code systematically leads to more conservative requirements, significantly increasing the number of required lashing devices compared to DNV guidelines. The influence of lashing angles is quantified, identifying optimal configurations that minimize securing effort while ensuring tipping equilibrium. The developed models accurately estimate the number of lashing devices required for both longitudinal and transverse tipping. Conclusions : The methodology is validated through a real case study involving heavy offshore cargo and provides practical decision-support tools. The proposed approach enables more efficient and reliable securing design in maritime cargo transport.