• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.4
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• pp.355-361
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• 2014

Steam explosions can be caused by fuel-coolant interactions resulting from failure of the external vessel cooling system in a new nuclear power plant. This can threaten the integrity of structures, including the nuclear reactor and the containment building. In the present study, an improved technique for analyzing the steam explosion phenomenon was proposed on the basis of previous research and was verified by simulations involving alumina experiments. Also, the improved analysis technique was applied to determine the pressure history of the reactor cavity in accordance with postulated failure locations. The results of the analysis revealed that the effects of vessel side failure are more serious than those of vessel bottom failure, with approximately 70% higher maximum pressure.

• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.4
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• pp.211-217
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• 2007

Due to advanced new weapons and changes in the combat environment, survivability improvement methods for naval ship design have continuously evolved. Surface naval ships are easily detected by the enemy and, moreover, there are many attack weapons that may be used against surface naval ships. Therefore, it is important for modem naval ships, especially combat naval ships, to ensure survivability. In order to design a naval ship considering survivability, the designers are required to establish reasonable attack scenarios. An explosion may induce local damage as well as global collapse of the ship. Therefore, possible damage conditions should be realistically estimated at the design stage. In this study, an ALE technique was used to simulate the explosion analysis, and the survival capability of damaged naval ships was investigated. Especially, the author have establish the simple method of estimation of survival time for damaged naval ships.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.2
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• pp.451-457
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• 2017

The numerical analysis was conducted to evaluate the behavior of slab-column connection subjected to blast loads using LS-DYNA. The typical form of slab-interior column connection for analysis was considered as a reference specimen and the drop panel slab-interior column was designed to verify the effects of drop panel. The slab-column connections, which were composed of interior, edge and corner column, were additionally analyzed to compare their confinement effects of specimens. Analysis results were contained the failure shape of connection, behavior of member and so on. From the results, the blast-resistant capacities of slab-column connection would be enhanced by reinforcing the drop panel. In addition, the performance of connections could be improved, when the confinement effects were enhanced.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.34 no.6
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• pp.393-401
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• 2021

In this paper, we proposed a numerical model based on moment-curvature, to evaluate the resistance of reinforced concrete (RC) members subjected to blast loading. To consider the direct shear failure mode, we introduced a dimensionless spring element based on the empirical direct shear stress-slip relation. Based on the dynamic increase factor equations for materials, new dynamic increase factor equations were constructed in terms of the curvature rate for the section which could be directly applied to the moment-curvature relation. Additionally, equivalent bending stiffness was introduced in the plastic hinge region to consider the effect of bond-slip. To verify the validity of the proposed model, a comparative study was conducted against the experimental results, and the superiority of this numerical model was confirmed through comparison with the analytical results of the single-degree of freedom model. Pressure-impulse (P-I) diagrams were produced to evaluate the resistance of members against bending failure and direct shear failure, and additional parametric studies were conducted.

• Journal of the Korean Institute of Gas
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• v.3 no.3 s.8
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• pp.23-28
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• 1999

Variation of explosion characteristics by the blocks in closed vessel was investigated to analyse the effect of the block volume(volume blockage) and the surface area of the blocks(ratio of block surface area to vessel volume). Volume and surface area of blocks in explosion vessel were changed by the combination of blocks. The volume of explosion vessels was 270 liter, and the LPG-air or NG-air mixtures were ignited by the electric spark. Explosion pressure was measured with the strain type pressure transducer. From the experimental results, explosion pressure was decreased by the increase of the volume blockage and the block surface area. And the decrease of explosion pressure was more affected by the volume blockage than the surface area.

• Computational Structural Engineering
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• v.14 no.2
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• pp.11-17
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• 2001

• Computational Structural Engineering
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• v.20 no.3
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• pp.18-24
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• 2007

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2001.04a
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• pp.102-103
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• 2001

• Computational Structural Engineering
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• v.25 no.4
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• pp.57-62
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• 2012

• Bulletin of the Society of Naval Architects of Korea
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• v.51 no.3
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• pp.8-12
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• 2014