• Proceedings of the Computational Structural Engineering Institute Conference
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• 1993.04a
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• pp.27-34
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• 1993

Precast large panel structures behave differently form frame and monolithic wall structures under external loads, because of the distinct planes of weakness in the horizontal and vertical joints between panels. These joints may slide and open during shaking, producing large localized changes in the bending and shear stiffness of individual walls. The structural behavior of large precast panel buildings depends on the relative strength and stiffness of the panels and joints. Special modeling are thus required for the analysis of precast panel connections. This study suggests a new analytical modeling and method to obtain the rational estimation of discontinuity and slip movements form the connections of precast large panel structures .

• Journal of Welding and Joining
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• v.17 no.6
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• pp.78-83
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• 1999

Solder joint is the weakest part which connects in mechanically and electronically between package body and PCB(Printed Circuit Board). Recently, the reliability of solder joint become the most critical issue in surface mounted technology. The solder joint interconnection between plastic package and PCB is susceptible to shear stress during thermal storage due to the mismatch in coefficient of thermal expansion between plastic package and PCB. A general computational approach to determine the effect of solder joint shape on the fatigue life presented. The thermal fatigue life was estimated from the engelmaier equation which was obtained from the temperature cycling loading($-65^{\circ}C$ to $150^{\circ}C$). As result of the simulation, TSOP structure has the shortest thermal fatigue life and the same structure Copper lead has 2.5 times as much fatigue life as Alloy 42 lead. In BGA structure, fatigue life time extended 80 times when underfill material exists.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.176-183
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• 2008

This paper highlights the importance of carrying out global slope stability analysis as part of design calculations for geosynethetic walls in tiered configuration. Four design case histories were selected to examine the appropriateness of their design by performing additional slope stability analyses using the shear strength reduction method with in the frame work of finite element analysis. The results indicated that all of the walls examined, which were designed to meet the current design guide lines, did not satisfy the global slope stability requirement, and that longer reinforcements are required in the upper tiers to achieve the minimum factor of safety. Practical implications of the findings are discussed.

• International Journal of High-Rise Buildings
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• v.1 no.4
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• pp.247-254
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• 2012

In order to improve the seismic behaviors of traditional steel-concrete mixed structure, a novel steel concrete mixed structure consisting of steel frames braced with buckling restrained braces (BRBs) and a concrete tube is proposed. Based on several assumptions, the simplified mechanical model of the novel mixed structure is established, and the shear and bending stiffness formulas of the steel frames, BRBs and concrete tube are respectively introduced. The equilibrium differential equation of the novel mixed structure under horizontal load is developed based on the structural elastic theory. The simplified algorithms to determine the lateral displacement and internal forces of the novel mixed structure under the inverted-triangle distributed load, uniformly load and top-concentrated load are then obtained considering several boundary conditions and compatible deformation conditions. The effectiveness of the simplified algorithms is verified by FEM comparison.

• Bulletin of the Society of Naval Architects of Korea
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• v.22 no.4
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• pp.17-27
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• 1985

In this paper, an approximate calculation method on the transverse strength of oil tankers by use of slop-deflection method os described which considers the effect of shear deflection and varing section in elements and the result of calculation in models and actual ships, is presented. The object of this paper is focused on the development of program which can be used widely regardless strut numbers in transverse frame rings. To examine the reliability of the above method, the results in this paper are compared with the results which are obtained by use of SAP4(Structure Analysis Program) based on finite element method. The application of the Slope-Deflection Method on the transverse strength of oil tankers has the advantage that this method takes less than the other methods in calculation.

• Journal of Korean Association for Spatial Structures
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• v.4 no.4 s.14
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• pp.85-89
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• 2004

A frame element embedded normal to a shear wall or slab (shell element) is common in the structural systems. In that case there is a need for a membrane or shell element to have a normal rotation degree of freedom at each node in order to have a good result of stresses. Even if Many other people studied this area, All man, Cook and Sabir are representative investigators in this area. In this research paper, Sabir's methods of vertex rotation stiffness matrix in a membrane element are studied. New stiffness of vertex rotation are proposed by taking advantage of beam stiffness theory. Rectangular elements stiffness with rotational degree of freedom are compared in accuracy ratio each other.

• Structural Engineering and Mechanics
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• v.5 no.6
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• pp.775-784
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• 1997

A unified theory is presented for the shape analysis of curved surface with a single layer structure composed by frame, membrane or shell. The shapes produced by the theory have no shear stress in elements, and the stress states in the whole shape are as uniform as possible under an ordinary load. The theory starts from defining an element potential function expressed by the measurement of the element length or the element area. Therefore, the shape analysis can produce various forms according to the definition of the potential function, and each of those form or the cable net form with the potential function of the second power of element length is simply gotten by the linear analysis. The form in tensile stress is mechanically equal to an isotropic tension form.

• Journal of the Korea Concrete Institute
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• v.11 no.3
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• pp.3-12
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• 1999

This study presents a suggestion of regulation of skewed slab bridge. In order to find the characteristic behavior of skew bridge, many cases of skew bridges were analyzed with changed angle of skew. The comparison of design methods for cantilever part in pier was also made. It was found that : (1) The lower the skew angle was, the higher the maximum support reaction forces at the end point were. (2) The higher the ratio of L/B was, the higher the maximum support reaction force at the point was. (3) The effect of skew may be neglected for skew angles of $70^{\circ}$or more. (4) If elastic springs are applied to the boundary conditions to simulate the rubber pad bearings, the results will be more reasonable. (5) The shear deformation effect must be considered in the analysis of cantilever part of substructure. (6) Using strut and tie model to design cantilever part of pier, it will be more simple than finite element method with same accuracy and more accurate than using frame element.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.3 s.246
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• pp.215-221
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• 2006

A stereoscopic particle tracking velocimetry (SPTV) technique based on the 2-frame hybrid particle tracking velocimetry (PTV) method was developed. The expansion of 2D PTV to SPTV is facilitated by the fact that the PTV method tracks individual particle centroids. To evaluate the performance and measurement accuracy of the present SPTV technique, it was applied to flow images of rigid body translation and synthetic standard images of jet shear flow and impinging jet flow. The data processing routine and measurement uncertainty of the SPTV technique are compared with those of conventional stereoscopic particle image velecimet.y (SPBV). In addition, the centroid translation effect of 2D particle image velocimetry (PIV) is defined and its effect on SPIV measurements is discussed. Compared to the SPIV method, the SPTV technique has inherited merits of concise and precise velocity evaluation procedures and provides better spatial resolution and measurement accuracy.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.10a
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• pp.305-312
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• 1999

A four-story reinforced concrete frame building model is designed for the gravity loads. only Static nonlinear pushover analyses are performed in two orthogonal horizontal directions. The overall capacity curves are converted into ADRS spectra and compared with demand spectra. At several points the deformed shape moment and shear distribution are calculated. It is observed that the seismic capacity may not meet the design requirements in soft soil condition and may collapse in MCE. It is concluded that limited but adequate amount of ductility need be provided in the seismic design in low to moderate seismicity regions.