• Journal of Welding and Joining
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• 제33권6호
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• pp.49-54
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• 2015

Welding process is of importance to assemble products or structures, but also the process is structural weakness due to stress concentration in welding joint. The fatigue design of welded joint requires time & labor consuming fatigue test because the fatigue life is various according to the depth of joint, joint type and load type etc. In fatigue design codes, they guide to classify welding joints with their shape( BS7608, IIW Documents) and provide fatigue assessment information. In terms of numerical method for fatigue analysis, it is also difficult to decide the stress peak in joint because of mesh sensitivity which means that stress value is varies with element type or size on stress concentration zone. Hot-spot method is used generally, but Battelle of United States proposed Master S-N Curve based on structural stresses converted by mechanical equilibrium theory. In this research, we extracted master S-N curve from Battelle's fatigue test DB including test data of various welding joints to apply on Non-Load-Carrying cruciform Joint. Comparing fatigue results between the case of using normal stress and case of structural stress cor the cruciform Joint, The suggested Battelle method showed successive results.

• 한국도로학회논문집
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• 제13권1호
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• pp.223-228
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• 2011

본 논문에서는 포스트텐션 콘크리트 포장(PTCP: Post-Tensioned Concrete Pavement)과 줄눈 콘크리트 포장(JCP: Jointed Concrete Pavement)이 접속되는 터미널 조인트의 시공시 초기 줄눈 폭 설계에 대하여 연구하였다. PTCP와 JCP 사이의 줄눈 폭은 소음과 승차감에 직접 영향을 미치는 요소이다. 초기 설계 줄눈 폭이 지나치게 크면 소음과 승차감을 저하시키고, 줄눈 폭이 지나치게 작게 되면 온도 상승시 슬래브의 팽창과 블로우업 발생으로 압축응력이 과도하게 작용하여 줄눈부 파손을 야기할 수 있기 때문이다. 본 연구는 온도변화에 따른 터미널조인트의 줄눈 폭의 연구를 위하여 PTCP와 JCP가 시공된 동해고속도로 주문진현장에서 2010년 8월과 11월에 줄눈 폭 데이터를 측정하고 분석하여 최적의 줄눈 폭 설계방안을 제시하였다.

• 한국강구조학회 논문집
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• 제12권5호통권48호
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• pp.537-547
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• 2000

현장에서 자주 사용하는 강관 플랜지이음은 고력볼트를 사용한 인장접합의 일종이다. 이 이음에 있어서 응력전달은 고력볼트를 조을때 얻어지는 재료간의 높은 압축력을 이용해서 행하여진다. 그리고 플랜지이음의 역학성상에 대해서 충분하게 해명되어 있지 않고 설계방법도 확립되어 있다고 말하기 어렵다. 이상의 문제점을 포함한 플랜지이음에 대해서 종국내력에 착안을 둔 설계법을 제안하고자 한다. 본 연구의 목적은 리브 붙은 고력볼트 강관 플랜지의 이음에 대한 설계방법을 세우기 위한 기초자료를 얻는데 있고 또한 리브나 링이 개입된 형식에 있어서 직경이 다른 강관 플랜지의 이음이 설계될 수 있는지 조사하는데 있다.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1995년도 특별강연 및 추계학술발표 개요집
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• pp.145-148
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• 1995

To provide better understanding of a solder joint design criteria, mathematical models have been developed to calculate the shape of the solder fillets formed between the pad and lead. The effects of parameters such as solder volume and pad dimensions are described with this model. In this study, a systematic way to determine the design criteria of the SMT from the predicted 3D solder joint profile is proposed. The solder joint profile is calculated using the available 3D FEM code which minimizes the system energy due to the surface tension and gravity. The solder joint profiles of gullwing-type lead such as QFP and SOP are calculated for design parameters, and acceptable ranges are obtained. The result shows that the pad length is the most significant factor compared with the pad width and pad area.

• The Journal of the Acoustical Society of Korea
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• 제17권1E호
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• pp.66-69
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• 1998

Idle shake vibration characteristics of a vehicle are mainly influenced not only by the stiffnesses of the beam type structures such as pillars and rockers, but also by the stiffnesses of the joint structures, at which several beam structures are jointed together. In the early design stage of the car body structure a simple FE model has been used, in which joints are modeled as linear springs to represent the stiffnesses of the joint structures. In this paper a new modeling technique for the joint structure is presented using an equivalent beam, instead of using a spring. The modeling technique proposed is utilized to design optimal joint structures that meet the required vibration performance of the total vehicle structure.

• International Journal of Aeronautical and Space Sciences
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• 제17권3호
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• pp.332-340
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• 2016

A design optimization is performed for the double-bolted joint in cylindrical composite structures by using a simplified analytical method. This method uses failure criteria for the major failure modes of the bolted composite joint. For the double-bolted joint with a zigzag arrangement, it is necessary to consider an interaction effect between the bolt arrays. This paper proposes another failure mode which is determined by angle and distance between two bolts in different arrays and define a failure criterion for the failure mode. The optimal design for the double-bolted joint is carried out by considering the interactive net-tension failure mode. The genetic algorithm (GA) is adopted to determine the optimized parameters; bolt spacing, edge distance, and stacking sequence of the composite laminate. A purpose of the design optimization is to maximize the burst pressure of the cylindrical structures by ensuring structural integrity. Also, a progressive failure analysis (PFA) is performed to verify the results of the optimal design for the double-bolted joint. In PFA, Hashin 3D failure criterion is used to determine the ply that would fail. A stiffness reduction model is then used to reduce the stiffness of the failed ply for the corresponding failure mode.

• 한국의상디자인학회지
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• 제25권3호
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• pp.127-141
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• 2023

The purpose of this study is to develop a textile pattern design using the columnar joints motif and a Tyvek fashion clutch bags using it. As a research method, first, through a literature review, columnar joint and Tyvek are understood, and design cases were considered. Second, through a survey, the purchase perception and design preference of columnar joints cultural products were analyzed. Third, based on the results of the survey on color and print, the pattern design for each type of columnar joint were developed, and the uv-printed Tyvek clutch bag was developed. The results of this study are as follows. First, the reason why the public was not attracted to the purchase of cultural products was dissatisfaction with practicality, price adequacy, and aesthetics. Therefore, it was analyzed that quality, practicality, price, carry-on storage, collection value, and casualness, as well as aesthetic design were important factors for purchasing factors pursued by consumers. Second, consumers preferred small goods the most for cultural products, and they pursued the use of colorful and contrasting colors, modern and geometric patterns, and eco-friendly materials, such as Tyvek. Third, columnar joint can be classified into three cross sections and four arrangements. The design unit of the columnar joint could be expressed as a hexagonal column, and 12 different pattern designs could be developed according to the cross sections and arrangements type. In addition, it was found that it was easy to produce fashion products suitable for the sensibility of modern people by utilizing Tyvek materials.

• 대한기계학회논문집A
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• 제34권5호
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• pp.597-604
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• 2010

본 논문에서는 모바일하버의 하역 시스템으로 특화되어 개발한 제로 모멘트 크레인에 적용되는 조인트를 설계하고자 한다. 해당 조인트는 제로 모멘트 포인트의 개념에 기반하여 제로 모멘트 크레인을 안정화시키는데 중요한 역할을 수행한다. 이 목적을 위해서는 크고 다양한 형태의 하중을 견딜 수 있으며, 또한 2 방향의 자유도를 허용할 수 있어야 한다. 통상적인 설계 과정을 거쳐, 유니버셜 조인트와 스피리컬 조인트를 결합한 후 가변형 구름 요소를 적용한 새 디자인을 제안하였다. 구름 요소는 하중을 분산시키며 하역 과정 동안의 동력 손실을 줄여준다. 시스템의 복잡성과 최적화 과정의 효율성을 고려하여, 크리깅 기반 근사 최적화 기법을 선정하였다. 설계된 조인트를 검증하기 위해, 구조 해석을 수행하고, 축소 시제품을 제작하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.479-484
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• 2004

For the rational design of welded joint, it is needed to assess repeatedly the fatigue life of the joint with various dimensions and welding conditions. In this paper, an automation of repeated process of fatigue life assessment for welded cruciform joint was studied. The process is related to stress analysis in vicinity of weld-toe and fatigue life assessment based on analyzed stress distribution. With the change of design condition including dimensions and/or welding heat input, the above two works have to be performed. Using the commercial tool for system integration, ModelCenter, an automation of the repeated process for welded cruciform joint based on 2D modeling was achieved. In this automation system, data exchanges between programs regardless of commercial or in-house one work well, and parametric studies for optimal design can be performed.

• 한국실내디자인학회논문집
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• 제18권3호
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• pp.39-46
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• 2009

The purpose of this study is to analyze the meaning of 'dis-joint' in the works of Louis I. Kahn. Kahn tried to realize his main architectural thoughts of 'what it wants to be' and 'how it was done' through his whole life. The concept of 'dis-joint' had been developed to visualize his architectural thoughts. Kahn used' dis-joint' to show and emphasize the structural system for the raison d'etre of building. Kahn's 'dis-joint' can be categorized as 'spacing', 'butt', 'slit' and 'protrusion'. Kahn used this kind of unusual way of joint beyond simple exposure to stress the existence of element, part and building itself. Through variable combination usage of 'dis-joint', Kahn can realize his architectural thoughts into building in a concrete way. The efficiency and function of joint is not the main issue in his works. 'Dis-joint' was the concrete tool to show the tectonic of architecture and construction process to enhance its presence. Therefore 'dis-joint' of Kahn's architecture is not a joint only to combine building parts but a concrete mean to realize his thoughts in a corporeal way. These facts insinuate that Kahn's architectural philosophy is based on the thoughts of tectonic and its realization.