• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.110-113
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• 2010

해양플랜트 구조물은 대양에서 파력을 비롯한 바람 등과 같이 자연에 의해 발생하는 다양한 외력을 구조물 사용기간 동안 지속적으로 랜덤하게 받게 되므로 이로 인한 피로현상이 발생하게 된다. 특히 용접부로 이루어진 격점부는 복잡한 기하형상의 영향으로 피로에 대해 취약구조가 되므로 피로강도향상은 해양플랜트 구조의 안전성에 중요한 요인이 된다. 본 연구에서는 격점부에 대한 구조상세에 관련한 설계기준 및 평가방법을 조사하였으며, 고정식 Jacket 구조물을 대상으로 프레임요소를 사용하여 구조해석을 실시하여 공용하중에 대한 구조거동을 분석하였다. 또한 격점부의 강도평가방법 및 연결부 피로강도를 개선하기 위하여 프레임요소의 구조해석을 토대로 복잡한 기하형상을 가진 KT형 관이음부(Tubular Joints)에 대해 상세해석을 실시하였다.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.04a
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• pp.300-307
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• 1999

신경망기법을 이용한 구조물접합부의 손상평가기법을 제안하였다. 신경망기법의 성능을 개선하기 위하여 노이즈첨가학습을 수행하였으며 효과적인 손상평가를 위하여 부분구조추정법 및 data perturbation scheme을 도입하였다. 10층 프레임구조물에 대한 수치해석과 2층 프레임구조물에 대한 실험연구를 통하여 제안기법을 검증하였다 계측지점이 부분구조로 제한되고 계측자료가 노이즈를 포함하는 경우에는 제안기법이 효과적으로 적용될수 있음을 알 수 있었으며 실험을 통하여 실제 구조물에 대한 제안기법의 적용성을 평가힐 수 있었다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.1
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• pp.93-100
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• 2015

Modern wooden structures usually are connected with steel fastener type connectors. And joints using multiple connectors in wooden structures will form semi-rigid connection. If connection in wooden structure would be designed to be pinned joint, the underestimate for loads transmitted through connection, would result in the deficient capacity of resistance in connection. And if joints in wooden structures would be assumed to be fully-rigid joint, amount of fasteners needed at the connection could be excessively increased. It will give a bad effect in the view of beauty, constructability and economy. Estimate for the reasonable stiffness of connection might be essential in design of reasonable connection in wooden structure. This paper will suggest analysis modelling technique that can represent approximate stiffness of connections using a common analysis program for double shear connection in order to give help in performing easily the design of wooden structure. It is verified that the suggested approximate analysis modelling technique could represent the behavior in connection by comparing the analysis results with test results for tensile, bending moment.

• Computational Structural Engineering
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• v.4 no.4
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• pp.97-106
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• 1991

The frequency window method has been extended to include strong coupling and multiple connections between the primary structure and the secondary structures. The rational polynomial expansion of the eigenvalue problem and the analytical methods for its solution are novel and distinguish this work from other eigenvalue analysis methods. The key results are the identification of parameters which quantify the resonance and coupling characteristics; the derivation of analytical closed-form expressions describing the fundamental modal properties in the frequency windows; and the development of an iterative procedure which yields accurate convergent results for strongly-coupled primary-secondary structures.

• Magazine of the Korea Concrete Institute
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• v.8 no.3
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• pp.209-218
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• 1996

The purpose of the present study is to explore the effects of local reinforced type and to suggest reliable failure mechanism and the design criteria on the anchorage zones of the precast prestressed concrete bridges. To accomplish these objectives, a comprehensive experimental and analytical study has been conducted. From this study, the cracking and ultimate load capacities for spirally reinforced anchorage zone are found to be larger than those for orthogonal reinforced anchorage zone. This indicate the effectiveness of spiral reinforcement in controlling the cracking. And realistic failure mechanism and design criteria of prestressed anchorage zones based on the present study are suggested.

• Magazine of the Korea Concrete Institute
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• v.10 no.5
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• pp.101-107
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• 1998

본 논문은 비선형 스트럿-타이 모델에 의한 프리스트레스트 콘크리트 정착부의 거동해석 및 설계에 관한 연구이다. 프리스트레스트 콘크리트 구조물의 정착부는 긴장재의 인장력 도입으로 인해 비교적 작은 단면에 큰 집중하중으로 발생하는 매우 중요한 구조부위이며, 기존의설계가 비교적 다른 구조부위의설계에 비하여 경험적으로 이루어지고 있을 뿐 만 아니라 해석에도 많은 시간과 계산량이 소요되는 단점이 있다. 비선형 스트럿-타이 모델을 대상 정착부의 비선형 재료거동을 따르도록 비선형 해석을 실시하여 설계를 수행하고 구조물의 극한하중을 추정하는 방법이다. 본 논문에서는 긴장력이 정착부의 중앙에 도입되는 경우, 편심으로 도입되는 경우, 다중 정착구가 존재하는 경우에 대하여 선형과 비선형 스트럿-타이 모델을 구성하여 정착부의 역학적 거동을 고찰하였고 실험결과와 비교하였다. 비교로부터 비선형 모델을 사용한 경우 선형 모델을 사용한 경우보다 안정성을 유지하면서 경제적인 설계가 가능하고 추정극학강도도 실험결과에 더욱 근접함을 알았다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.14 no.4
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• pp.537-549
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• 2001

The effect of partially restrained(PR) connections and the uncertainties in them on the reliability of steel frames subjected to seismic loading is addressed. A stochastic finite element method(SFEM) is proposed combining the concepts of the response surface method(RSM), the finite element method(FEM), the first-order reliability method (FORM), and the iterative linear interpolation scheme. The behavior of PR connections is captured using moment-relative rotation curves, and is represented by the four-parameter Richard model. For seismic excitation, the loading, unloading, and reloading behavior at PR connections is modeled using moment-relative rotation curves and the Masing rule. The seismic loading is applied in the time domain for realistic representation. The reliability of steel frames in the presence of PR connections is calculated considering all major sources of nonlinearity. The algorithm is clarified with the help of an example.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.6
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• pp.775-786
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• 2022

In the plant structures including nuclear power plants, penetrations are frequently installed in walls and slabs to reinforce facilities during operation, and reinforcing bars are sometimes cut off during concrete coring. Since these penetrations are not considered at the design or construction stage, cutting of reinforcing bar during opening installation is actually damage to the structure, structural integrity evaluation considering the stress transition range or effective width around the new penetration is necessary. In this study, various nonlinear analyses and static loading experiments are performed to evaluate the effect of reinforcing bar cutting that occurs when a penetration is newly installed in the shear wall of wall-type building of operating nuclear power plant. In addition, the decrease in wall stiffness due to the installed new penetration and cutting of reinforcing bars is evaluated and the stress and strain distributions of rebars around penetration are also measured.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2001.11a
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• pp.331-336
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• 2001

경제규모의 증대와 사용부지의 제한으로 인하여 용접구조물들은 복합화, 대형화 추세에 있고, 이러한 경향에 따라 구조물에서 용접부가 차지하는 비중 역시 증가하고 있다. 용접과정을 통해 다양한 금속학적, 역학적 변화를 경험하게 되는 용접부는 대형 강 용접 구조물/설비의 건전성을 확보하기 위해서 가장 주의를 기울여야 하는 평가 대상 부위임에 분명하다.(중략)

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.6
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• pp.201-211
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• 2011

Many reinforced concrete structures have been constructed at the offshore in Korea and those are exposed in environments for long period. Due to that, the reinforcement of the structure faces possibility of corrosion by the salt damage. Such corrosions are effects on the bond performance between concrete and reinforcing bar as well as the performance of the structure. In this study, the performance of RC structure has been investigated when the reinforcing bars are totally bonded and unbonded in the structure. Through the experimental tests and finite element analyses of beam-column joint with bond and unbonded reinforcing bar, the energy dissipation capacity, strength, and crack distribution are compared and discussed.