Gjermundbufunnet – en småkonges grav med østlig tilsnitt på Ringerike

The Gjermundbu find came to light under difficult, wartime circumstances in 1943. With travel and other restrictions in place, a full-scale rescue excavation was not possible, and the find is poorly documented. What is certain, is that we are dealing with a very rich grave from the end of the 10th century, with few if any parallels outside the milieu of the large ship graves. The cremation grave held some very uncommon objects, like a helmet and a chain mail, as well as five or six horses and one or two sledges. While there are many similarities between the Gjermundbu find and the Vendel and Valsgärde burials in Sweden, the closest parallels to the find are the so-called druzhina burials in present-day Russia and Ukraine, and the authors suggest that the buried man was a petty king, who had served in the retinue of Vladimir the Great or one of his predecessors, together with other warriors from Ringerike.

AN EXPERIMENTAL STUDY OF SHIP MOTIONS DURING REPLENISHMENT AT SEA OPERATIONS BETWEEN A SUPPLY VESSEL AND A LANDING HELICOPTER DOCK

Hydrodynamic interactions during Replenishment at Sea (RAS) operations can lead to large ship motions and make it difficult for vessels to maintain station during the operation. A research program has been established which aims to validate numerical seakeeping tools to enable the development of enhanced operator guidance for RAS. This paper presents analysis of the first phase of scale model experiments and focuses on the influence that both the lateral and longitudinal separations between two vessels have on the interactions during RAS. The experiments are conducted in regular head seas on a Landing Helicopter Dock (LHD) and a Supply Vessel (SV) in intermediate water depth. The SV is shorter than the LHD by approximately 17%, but due to its larger block coefficient, it displaces almost 16% more than the LHD. Generally, the motions of the SV were larger than the LHD. It was found that hydrodynamic interactions can lead to large SV roll motions in head seas. Directions for future work are provided.

Principles and optimal design methods for large ship grillages

Based on the previously developed approach to structural ship design, the authors optimize a large-span deck grillage taking into account several design loading scenarios. Topological optimization made it possible to find an optimal structural layout of the grillage, and parametric optimization yielded the scantlings of beams and simultaneously reduced grillage weight. Additional gain in structural weight was achieved by means of the openings in beam webs.

Model Experimental Research of Ship Section on Structural Ultimate Strength

Focusing on the model design and experimental method research of ultimate strength of ship hull typical section, a large ship with complex section structure was taken in this paper as the research object. The nonlinear analysis on the failure mode and ultimate strength of the hull structure were carried out. The similarity model for ultimate strength experiment was designed, and the validity of the similarity model in reflecting the ultimate bearing capacity of the real ship was verified. According to the experimental results, the ultimate strength experimental value was obtained by numerical conversion. The ultimate bearing capacity of the example ship was then checked with reference to several classification society rules to verify the structural safety of the ship hull.

Calculation of Environmental Load for a Large FPSO Undocking

Ship undocking is an essential process in the construction of large ship. Nowadays, the traditional empirical method is usually used to calculate the environmental load during large ship undocking of large ship and to determine the power and number of assistant tugboats in the world shipbuilding industry. Firstly, the OCIMF with traditional empirical formula mathematical model for solving the environmental load problem is established in this paper. According to the location of the dry dock and the meteorological and hydrological conditions while undocking, the environmental load of a large FPSO with different wind, wave, and current combination from 0°to 90°are is calculated by using the OCIMF with traditional empirical formula method, and then the influence of the wind, wave and current load on large FPSO are is analyzed. Secondly, the environmental load is calculated by using numerical simulation calculation method based on the same environment conditions. Through comparing the analysis results between the two calculation methods, the reliability of using the OCIMF method is testified reliable to large barge-type FPSO, and the maximum environmental load is determined. Lastly, as a result the undocking plan and the power and number of assistant tugboats are finally determined. The actual undocking project shows that the OCIMF with traditional empirical formula method is reliable for calculating the environmental load of a large barge-type FPSO.