Lightweight Structural Concepts in Bearing Quasi-Static Ice Hull Interaction Loads

Lightweight ice-class vessels offer the possibility of increasing the payload capacity while making them comparable in energy consumption with non-ice-class vessels during ice-free periods. We approach the development of a lightweight hull by dividing ice-hull interactions into quasi-static loading and impact loading phases. Then, investigative outcomes of lightweight concepts for each loading phase may be combined to develop a lightweight ice-going hull. In this study, we focus on the quasi-static loading phase characteristic of thin first-year ice in inland waterways. We investigate metal grillages, sandwich structures and stiffened sandwich structures parametrically using the finite element method. The model is validated using previous experimental studies. In total over 2000 cases are investigated for strength and stiffness with respect to mass. The stiffened sandwich was found to be the most favorable concept that offered both a light weight as well as high gross tonnage. Further, significant parameters and their interactions and material differences for the three structural concepts were investigated and their trends discussed. The outcomes result in the creation of a viable pool of lightweight variants that fulfill the quasi-static loading phase. Together with outcomes from the impact loading phase, a lightweight ice-going hull may be developed.

Automated summary

Lightweight ice-class vessels have the potential to increase payload capacity during ice periods and match energy consumption with non-ice-class vessels during ice-free periods. This study focuses on analyzing different lightweight hull structures for ice interactions, particularly in the quasi-static loading phase. Parametric investigations using the finite element method show that stiffened sandwich structures are the most favorable concept, offering a balance between light weight and high gross tonnage. Further research on material differences and structural parameters provide insights into creating viable lightweight variants for ice-going hulls.