Background: The cargo stowage and securing plan for non-standardized cargo is vital for ensuring safety at sea, as improper placement or inadequate lashing can compromise maritime transport safety. Due to the diverse size and type of cargo, efficient planning is also essential to optimize space utilization and improve the economic performance of general cargo vessels. Methods: This paper presents a novel methodology to identify the optimal cargo securing layout using lashing lines that comply with international standards while minimizing deck space usage. A comparative analysis of two major securing guidelines was conducted to determine the stricter and safer standard. Results: The optimization approach was validated with real-world case studies, revealing the most effective securing configurations. These are defined by the optimal combination of vertical and horizontal lashing angles, which secure cargo in any stowage position by balancing longitudinal and transverse forces while minimizing occupied deck area. Additionally, novel graphs and 3D maps are introduced to illustrate the relationships between key securing parameters. Conclusions: The obtained results and the visual tools enhance understanding and provide practical support for lashing planners, facilitating safer and more efficient cargo securing decisions.

In recent years, both the number and the size of ships have increased considerably, whereas port areas have expanded much more slowly. As a result, port manoeuvres are increasingly performed in restricted waters, which increases navigational risk during ship operations. For this reason, ship-handlers must know the instantaneous position of the pivot point (PP) at any time. The aim of this paper is to propose novel mathematical models to determine the PP’s position and to identify the most relevant variables influencing it. For this purpose, a full-mission bridge simulator was used to generate a dataset based on multiple simulations performed under different combinations of rudder angles and engine telegraph orders. First, a new trigonometric formulation is proposed to determine the instantaneous position of the PP using only directly measurable variables, namely the speed through water and the transverse velocities at the bow and stern. Subsequently, additional predictive models were developed using Design of Experiments (DOE) and response surface techniques. These models achieve high predictive accuracy while remaining simple enough to be applied in practical ship-handling scenarios. The resulting models can assist ship-handlers in anticipating PP behaviour and improving manoeuvring safety, particularly in restricted waters. Original 3D charts showing the combination of several input variables are included to identify the map of the whole process.

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.