Meyer Turku (Finland)

Abstract Accurate and efficient analysis of ship and offshore glass structures is important because they are typically large and complex, and analysis time is often limited. Therefore, this article proposes an finite element (FE) modeling concept for analyzing laminated glass plates. The laminate glass increases the safety of windows thanks to the interlayer that joins two glass panes together, retaining fragments in case of breakage. The theory we use in this study follows the formulation from existing literature for sandwich plates with thick faces. We call this the equivalent double-shell model for laminated glass. The concept is validated against a full 3D solid-shell FE model, and the agreement is good regarding maximum deflection and stresses. Hence, using such a concept in analyzing actual large glass structures, for example, as part of a ship global model, becomes less computationally heavy.

In August 2023, the Finnish Institute for Health and Welfare received reports of a potential cluster of pneumococcal pneumonia cases among shipyard employees in Turku, Finland. Considering a similar outbreak in the same shipyard in 2019, we initiated a case–control study to investigate individual and environmental risk factors specific to this occupational setting in order to inform targeted prevention measures. In total, 14 hospitalized cases were identified from 19 August to 15 October 2023. Streptococcus pneumoniae serotypes 4 and 9 V were isolated from blood cultures of seven cases. Eleven cases and 67 controls working at the shipyard were included in the case–control study. Compared with controls, cases were more likely to be living in an apartment/studio or a hotel/hostel, and less likely in a house or with family. Furthermore, cases were more likely to have a shorter duration of employment (< 1 year) at the shipyard compared to controls. Control measures, including an information and a vaccination campaign, were implemented. We emphasize shipyard-wide hygiene improvements and recommend nationwide consideration of expanding pneumococcal vaccination eligibility to all shipyard construction employees as an occupational high-risk group.

This paper investigates weld root fatigue strength of complex structures including severe force concentrations along a weld seam. Fatigue tests were carried out for a pillar assembly with various weld configurations. A comparative analysis was carried out with local nominal weld stress (LNWS), structural weld stress, and effective notch stress (ENS) approaches. The study shows that the LNWS approach gives the best prediction, with a scatter range index of 1.26 to 1.68 depending on the weld type. The accuracy of the structural weld stress approach and ENS was significantly lower, with a scatter range index of 4.98 and 5.40, respectively.

ABSTRACTA new approach for analysing the level of survivability for a passenger ship in the event of a collision damage is presented. Monte Carlo simulation is used for generating a large number of damage cases. The probability distributions for damage extent and location are based on the current SOLAS regulation. Each case is calculated with time-domain flooding simulation, assuming quasi-static motions and calm sea, thus enabling evaluation of the righting lever curve during the flooding process. The ship survivability is analysed based on requirements for a sufficient reserve stability. The proposed method is demonstrated with a large passenger ship design. Based on the detailed investigation of the results, the effects of various design changes are studied. Furthermore, the impact of waves on the flooding process is studied. The presented method for survivability assessment is robust and especially suitable for comparing design variations, or ships with similar main dimensions.