Establishment of Ship-Motion-Based Operational Limiting Criteria for Safe and Efficient Offshore Cable-Laying Operations

As offshore wind projects are located further and deeper in the ocean, time-intensive and costly cable laying plays an increasingly critical role in offshore wind farm construction. Cable laying can be designed and operated based on the critical motions of the laying ship to potentially improve the operational window. However, there is no complete procedure for establishing ship-motion-based operational limiting criteria to ensure sufficient safety while balancing efficiency. This paper proposes a complete algorithm for designing cable-laying operations by employing specific ship-motion characteristics as operational limiting criteria, based on their strong correlation with the dominant structural response, e.g., the minimum effective cable tension. A reduction factor β is introduced as an indicator for limiting criteria selection and value determination. This guarantees operational safety without compromising efficiency. The determined value of the limiting criteria is independent of the applied fitting function used in correlation analysis, thus offering greater adaptability. By dynamically selecting ship-motion indicators across different ship headings, the proposed algorithm extends the operational window by approximately 10% compared to conventional Hs-based limits, while improving utilization in hazardous sea states by approximately 50%. The effects of ship motion statistical description, laying conditions, and fitting strategies on operational windows are also discussed. The proposed algorithm provides an improvement of cable-laying operation design, leading to safer and smarter marine operations in real-time.