• 한국강구조학회 논문집
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• 제28권4호
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• pp.293-301
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• 2016

건플랜트 내부의 주요 시설물인 원통형 액체저장탱크에 지진 하중이 작용하면 탱크 벽체에 좌굴이 발생하여 큰 손실을 초래할 수 있다. 탱크 구조물 설계시 좌굴에 대한 허용응력을 규정한 국내 기준은 일관성이 부족하고 근거가 미약하여 주로 국외의 API 650, BS EN 1998-4:2006, 뉴질랜드 기준 등을 차용하고 있다. 본 연구에서는 서로 다른 형상 비를 갖는 탱크 구조물에 대해 응답스펙트럼해석을 수행하여 유체 동압력을 산정한 후 재료 및 기하비선형을 고려한 비선형 좌굴해석을 수행하여 축방향 허용좌굴응력을 산정하고 국외 기준과의 비교를 통해 적절한 국내 기준을 제안하였다.

• Structural Engineering and Mechanics
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• 제10권6호
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• pp.533-543
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• 2000

To prevent major cracking and failure during earthquakes, it is important to design reinforced concrete liquid storage structures, such as water and fuel storage tanks, properly for the hydrodynamic pressure loads caused by seismic excitations. There is a discussion in recent Codes that most of the base shear applied to liquid containment structures is resisted by inplane membrane shear rather than by transverse flexural shear. The purpose of this paper is to underline the importance of the membrane force system in carrying the base shear produced by hydrodynamic pressures in both rectangular and cylindrical tank structures. Only rigid tanks constrained at the base are considered. Analysis is performed for both tall and broad tanks to compare their behavior under seismic excitation. Efforts are made to quantify the percentage of base shear carried by membrane action and the consequent procedures that must be followed for safe design of liquid containing storage structures.

• Structural Engineering and Mechanics
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• 제13권4호
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• pp.355-368
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• 2002

In this paper, we address the numerical investigation on the effect of liquid compressibility onto the natural frequency of liquid-filled containers. Traditionally the liquid motion has been treated as an ideal fluid motion. However, from the numerical experiments for the axisymmetrical free-vibration of cylindrical liquid-storage tanks, we found that the relative difference in natural frequencies between ideal and compressible motions becomes remarkable, as the slenderness of tank or the relative liquid-fill height becomes larger. Therefore, in such cases of dynamic systems, the liquid compressibility becomes an important parameter, for the accurate vibration analysis. For the free-vibration analysis of compressible liquid-structure interaction we employed the coupled finite element formulation expressed in terms of the acoustic wave pressure and the structure deformation.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1999년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall
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• pp.83-90
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• 1999

This paper presents a method of seismic analysis for a cylindrical liquid storage structure on horizontally layered half-space considering the effects of the interior fluid and exterior soil medium in the frequency domain. the horizontal and rocking motions of the structures are included in this study. The fluid motion is expressed in terms of analytical velocity potential function which can be obtained by solving the boundary value problem including the sloshing behavior of the fluid as well as deformed configuration of the structure. The effect of the fluid is included in the equation of motion as the impulsive added mass and a frequency-dependent convective added mass along the nodes on the wetted boundary with structure. The soil medium is presented using the 3-D axisymmetric finite elements and dynamic infinite elements. The present method can be applied to the structures embedded in ground as well as on ground since it models the soil medium directly as well as the structure. For the purpose of vertification dynamci characteristics of a tank on homogeneous half-space is analyzed. Comparison of the present results with those by others shows good agreement.

• 한국축산시설환경학회지
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• 제14권1호
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• pp.1-8
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• 2008

This study was conducted to solve the problem of public grievance owing to odor of a pig farm. Odor emissions from pig production systems mainly originate from liquid manure storage and solid manure fermentation. The low-cost odor abatement system (OAS) for application at liquid manure storage tank and solid manure fermentation facilities was developed in this study. The OAS adapted odor removing principles of a biofilter and biotrickling filter. The OAS is very simplified in structure. The appearance of the OAS had a form of cylindrical or cubical shape. The system performance was monitored for about one year after stabilization. A 7 seconds empty bed contact time for the OAS was adapted to achieve the odor reduction levels. The commercial type of OAS was constructed with media comprised of wood chips. Moisture content always remained above 50% wet basis. Average ammonia removal efficiency for the developed design was 89% at the liquid manure storage tank. Also, the removal efficiency at a solid manure fermentation facility was 86% on ammonia.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1412-1415
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• 2005

Special considerations on the design of liquid storage tanks should be taken into account for seismic and wind loads. But Korean industrial standard KS B 6225 does not specify detailed guidelines for a design. It is therefore necessary to improve design guidelines for a seismic and wind-proof design in KS B 6225. The purpose of this study is provide a basis for the development of improved seismic and wind-proof design procedures, especially about seismic and wind loads.

• Structural Engineering and Mechanics
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• 제13권6호
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• pp.653-670
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• 2002

In order to ensure the structural dynamic stability of moving liquid-storage containers, the flow motion of interior liquid should be appropriately suppressed by means of mechanical devices such as the disc-type elastic baffle. In practice, the design of a suitable baffle requires a priori the parametric dynamic characteristics of storage containers, with respect to the design parameters of baffle, such as the installation location and inner-hole size, the baffle number, and so on. In this paper, we intend to investigate the parametric effect of the baffle parameters on the transient dynamic behavior of a cylindrical fuel-storage tank in an abrupt vertical acceleration motion. For this goal, we employ the ALE (arbitrary Lagrangian-Eulerian) kinematic description method incorporated with the finite element method.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1999년도 가을 학술발표회 논문집
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• pp.257-266
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• 1999

This paper presents a method of seismic analysis for a cylindrical liquid storage structure on/in horizontally layered half.space considering the effects of the interior fluid and exterior soil medium in the frequency domain. To capture the essence of fluid-structure-soil interaction effects effectively, a mixed finite element with two-field (u, p) approximation is employed to model the compressive inviscid fluid, while the structure and soil medium are presented by the 3-D axisymmetric finite elements and dynamic infinite elements. The present FE-based method can be applied to the system with complex geometry of fluid region as well as with inhomogeneous near-field soil medium, since it can directly model both the fluid and the soil. For the purpose of verification, dominant peak frequencies in transfer functions for horizontal motions of cylindrical fluid storage tanks with rigid massless foundation on a homogeneous viscoelastic half.space are compared with those by two different added mass approaches for the fluid motion. The comparison indicates that the Present FE-based methodology gives accurate solution for the fluid-structure-soil interaction problem. Finally, as a demonstration of versatility of the present study, a seismic analysis for a real-scale LNG storage tank embedded in layered half.space is carried out, and its member forces along the height of the structure are compared with those by an added mass approach developed by the present writers.

• 동력기계공학회지
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• 제9권4호
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• pp.65-70
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• 2005

A liquid storage rectangular tank structures are used in many fields of civil, mechanical and marine engineering. Especially, Ship structures have many tanks in contact with inner or outer fluid, like ballast, fuel and cargo tanks. Fatigue damages are sometimes observed in these tanks which seem to be caused by resonance with exciting force of engine and propeller. Vibration characteristics of these thin walled tanks in contact with fluid near engine propeller are strongly affected by added mass of containing fluid. Therefore it is essentially important to estimate the added mass effect to predict vibration of the tank structures. Many authors have studied vibration of cylindrical and rectangular tanks structures containing fluid. Few research on dynamic interaction among tank walls through fluid are reported in the vibration of rectangular tanks recently. In case of rectangular tanks, structural coupling between adjacent panels and effect of vibration modes of multiple panels on added mass have to be considered. In the present paper, coupling effect between panels of tank structure on added mass of containing fluid, the effect of structural constraint between panels on each vibration mode for fluid region have investigated numerically and experimentally.