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This study presents a comprehensive analysis using the finite element method (FEM) to examine and evaluate the behavior of fuel carrier ship structure. Sandwich panels are effective structures for use in ship structures due to their lightweight yet robust nature. Sandwich panels used in ship structures have various core shapes, such as hexagonal, circular, and square, as needed. The sandwich panel structure can be widely implemented in ship construction, for example, on the deck, hull, and bulkhead of the ship’s cabin. Hydrogen is an alternative fuel that can replace fossil fuels. In this modern era, hydrogen is high valuable energy commodity, so accidents involving carrier ships could have significant consequences. Hydrogen is produced from liquefied natural gas (LNG), so if a leak occurs, for instance, in a storage tank or fuel tank, it has the potential to lead to accidents such as fires. Corrosion is a significant concern for the maritime industry, as it can jeopardize the structural integrity of these vessels and pose substantial safety and environmental risks. In this research, FEM was utilized to model and simulate the effects of corrosion on hydrogen carrier ships when exposed to fire, considering various environmental and operational factors. Through a systematic investigation, it is aimed to gain insights into the impact of corrosion on ship structural components during fires, such as hulls and storage tanks. The result of this study will contribute to improving corrosion and fire mitigation strategies, ensuring the safety and longevity of hydrogen and LNG carrier ships, and supporting the sustainable transportation of hydrogen to meet global energy demands. No research has been conducted on the structural behavior resulting from hydrogen fires and corrosion simultaneously. To achieve this, it is assumed to use the corrosion properties of steel in heavily traveled ship routes such as the Panama Canal Zone, Barent Sea, North Sea, and Suez Canal Zone. This study utilized an approach by modeling corrosion using shell thickness in Abaqus Quasi-Static and applying boundary conditions in the form of temperature increase up to 800°C and subsequent cooling back to the initial temperature. At the maximum temperature, the most significant mid-span displacement occurred in the circular core sandwich panel, with a value of 4 mm. The axial force in the structure was inversely proportional to the mid-span displacement. In the case of the circular core sandwich panel, the axial force was 96 kN. The most resilient core type was hexagonal because it experiences the least deformation when compared to circular and square cores.

Ocean thermal energy conversion (OTEC) is a floating platform that generates electricity from seawater heat. The cold water pipe (CWP) used in OTEC has a length of 1,000 m and a diameter of 10 m, making it susceptible to bending loads from ocean currents. To find suitable geometry and material for the CWP, the finite element method was used to model the real-world geometry. In the D/t variation, lower ratios (increased thickness) result in higher critical moments, maximum stress, strain, and displacement. D/t 50 was chosen for the CWP. In the L/D variation, the critical moment’s impact on L/D ratio was minimal, while reducing L/D (shorter pipe) increased strain, and larger L/D geometries had higher displacements. L/D 10 was selected as it balanced critical moments and reduced the number of stiffeners needed. For diameter size variation, larger diameters increased critical moment and strain, but smaller diameters (larger L/D ratios) also showed high strain due to necking at two points. A diameter of 12 m was chosen for its exceptionally high critical moment. Steel was selected as the suitable material due to its higher critical moment and maximum stress, despite its higher weight and lower maximum strain than composites. Capital shape imperfections had a minimal effect on the CWP’s structure as they were localized.

Antiballistics are used as personal protective equipment required by military and police personnel. They have been mentioned frequently in recent decades due to the increasing cases of war. Several studies have reviewed the development of antiballistic technology. However, there needs to be more discussion on and systematic reviews of the current milestones of antiballistic materials, testing, and procedures. In addition, compared to other fields, antiballistic studies are rarely carried out by public researchers because research on weapons is still a sensitive topic. Researchers who want to discuss antiballistics must cooperate with the country's defense and security agencies. This article aims to present a summary on and the development of scientific research on the theoretical concept of impact, the experimental approach for ballistic tests on advanced materials, the idealization of ballistic tests in computational mechanic simulations, and milestones of technical apparatus for ballistic performance measurement, over a period of more than 500 years. Thus, this analysis makes an excellent contribution to the field of antiballistics. This article review is based on hundreds of international journals and websites that are still active and can be accounted for legally. The results show that research related to antiballistics will continue to grow yearly.

This article aims to investigate the structural behavior of beam–column joints subjected to axial force. The geometry used is the addition of a number of beam connections to the column, and the differences in the numbers of beams used are 1, 2, 4, and 4, denoted as V1, V2, V3, and V4, respectively.

This paper presents a numerical procedure based on the finite element (FE) method using ANSYS Workbench software to analyse fatigue phenomena in ship structures. Fatigue failure prediction is used as a stress–life approach, when the stress is still in a linear area. This condition is frequently referred as high-cycle fatigue. Five geometric shapes taken from midship points on the structure of a ship are sampled. There are four types of materials: HSLA SAE 950X, medium-carbon steel, SAE 316L, and SAE 304L. The types of loading imposed on each sample include three conditions: zero-based, zero mean, and ratio. Mesh convergence analysis is conducted to determine the most effective mesh shape and size for analysing the structure. The results showed that the configuration of the geometric shapes, materials used, loading schemes, and mean stress theory affect the fatigue characteristics of the structure.

In this study, a numerical investigation tensile test using ANSYS on three different carbon and alloy sheets of steel: AISI 1030 medium carbon steel, AISI 1080 high carbon steel and high-strength low-alloy (HSLA) A606 steel, has been carried out. The influences of three different specimen geometries on the stress–strain curve were also investigated. Understanding the properties of these materials, such as stress–strain obtained from a tensile test, is important. Materials are subjected to forces or loads when in use, for example, steel in a ship’s hull experiences significant stresses and strains. In such situations, it is necessary to understand the characteristics of the material because grounding or collisions can occur, which deform the materials. The differences in stress and strain obtained from three specimens with different geometries and mesh sizes of 2.5, 5, 7.5, and 10 mm for all proposed steels, were observed. The results showed that the ultimate tensile strength was always lower in specimen 2 compared to the other specimens. Furthermore, the highest von Mises stress and strain contour was located in the midsection of specimens 1 and 3 in all of the proposed materials.

Mechanical alloying can be carried out by a method known as friction stir processing, whereby solid Zn particles in a solution are distributed onto an aluminium alloy plate. The aim of this study was to determine the effects of a volume of Zn particles on the mechanical and physical properties of aluminium 1xxx alloy that had been subjected to friction stir processing. The specimens were plates composed of 1xxx series aluminium. A groove, measuring 12 mm in diameter, was pierced to various depths, and the Zn particles in these containers were then subjected to friction stir processing using a pin-less tool with a diameter of 15 mm. The results showed that the highest hardness was found in the uppermost layer of the workpiece, and this gradually decreased with thickness. An increase in the amount of Zn particles caused an increase in material hardness. The highest hardness of 87.1 HV in the friction stir-processed AA1100 was obtained at the highest volume of Zn compared to the hardness of 44.5 HV, which was obtained for the specimen without the addition of Zn.