• 대한기계학회논문집A
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• 제20권1호
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• pp.135-145
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• 1996

Order of stress singularities at bonded Edge Corners with two or three dissimilar isotropic Materials is analyzed. The problem is formulated by Mellin transform and characteristic equation is obtained as a determinant of matrix considering boundary conditions. Roots of characterictic equation are determinde by numerical calculations with ward method, from which the order of stress sigularities is obtained. Applying the results to the electronic packaging, the order of stress singularities is obtained. Applying the results to the electronic packaging, the order of stress singularities at bounded edge corners is calculated as a various bouned edge angle with given material combinations. Comparing the results, the optimal material combinaitons of bounded edge corners and bouned edge angle to reduce stress singularity could be determined. It suggests that the results are used to the basic design of electronic packaging reducing the stress singularity.

• 전산구조공학
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• 제10권2호
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• pp.131-138
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• 1997

이 논문에서는, 균일한 횡방향 인장변형률이 작용하는 조건에서 강체모재들을 결합하고 있는 점탄성 접착재층의 계면모서리에 발생하는 응력 특이성을 조사하고있다. Williams방법을 응용하여 라플라스 변형공간에서 특성방정식을 구하였고, 주어진 점탄성 모델에 대해서 변형공간에서의 특성방정식을 시간공간으로 해석적으로 전환하였다. 시간 공간에서의 특이차수는 수치적으로 계산하였다. 계면을 따라 발생하는 응력의 특성을 조사하는데 시간영역 경계요소법을 적용하였다. 수치해석 결과에 의하면, 특이차수는 시간이 경과함에 따라 커지는 반면에, 자유모서리 응력확대계수는 시간에 따라 이완되는 특성을 보여주고 있다.

• 산업기술연구
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• 제18권
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• pp.363-370
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• 1998

This study focused on the development of an alternative stress estimation procedure to instantly calculate the critical stresses bonded concrete pavement. Closed form analysis is commonly used to analyze pavement structures. This type of analysis assumes linearelastic material properties and static loading conditions. The well-known ILLI-SLAB finite element program was used for the analysis. Bonded concrete overlay analyzed the stress distribution, behavior and load carrying capacity under track load is made evaluation standard of bonded concrete overlay. In the study, the following results were derived ; The properties of strength is that compress and 3-point bending strength of existing pavement is deteriorated with $184kg/cm^2$, $59kg/cm^2$ but compress and splitting tensile strength of overlay is satisfied with $465kg/cm^2$, $45kg/cm^2$. Load transfers is happen at adjacent slab by interlocking under track load. The stress distribution under interior, corner and edge load is described high loading position surrounding then loading position.