• Structural Engineering and Mechanics
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• 제35권5호
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• pp.617-630
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• 2010

Different types of moment resisting connections are commonly used to transfer the induced seismic moments between frame elements in an earthquake resisting structure. The local connection behavior may drastically affect the global seismic response of the structure. In this study, the finite element and experimental seismic investigations are implemented on two frequently used connection type to evaluate the local behavior and to reveal the failure modes. An alternative connection type is then proposed to eliminate the unfavorable brittle fracture modes resulted from probable poor welding quality. This will develop a reliable predefined ductile plastic mechanism forming away from the critical locations. Employing this technique, the structural reliability of the moment resisting connections shall be improved by achieving a controllable energy dissipation source in form of yielding of the cover plates.

• Journal of the Korean Wood Science and Technology
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• 제41권5호
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• pp.415-424
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• 2013

The goal of this study is to analyze the effects of geometries of mortise and tenon on moment carrying capacity of the "sagae" connection. Effects of different tenon widths, mortise depths of connection from the top and bottom beams on stress distribution were investigated using the finite element method (FEM). Critical normal and shear stresses occurred at the reentrant corner from the mortise of the bottom beam. The maximum moment carrying capacity of the sagae connection from the FEM was validated from the results of experimental test. Maximizing moment carrying capacity of the sagae connection was found when the tenon width and mortise depth from the two beams were 40 mm and 60 mm, respectively.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.1003-1008
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• 2001

It is recently reported that bond failure can be initiated in the region where maximum bending moment and shear force is acted by accompanying shear deformation after flexural crack in full-scale RC beams strengthened by CFRP. Such a shear deformation effect causing bond failure is relatively little in the case of small-scale specimens. So, additional reinforcing details to the critical beam section where maximum moment and shear were acted is required to prevent the bond failure caused by the shear deformations. The U-type wrapping methods by CFRP to the critical beam section is proposed and tested in this paper. Also, the applicability of design bond strength derived from the tests of small-scale beam was investigated by the full-scale RC beam strengthened by CFRP.

• International Journal of Concrete Structures and Materials
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• 제8권1호
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• pp.1-14
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• 2014

In the present paper, a behavioral model is proposed for study of the individual contributions to shear capacity in shear-critical reinforced concrete members. On the basis of the relationship between shear and bending moment (V = dM/dx) in beams subjected to combined shear and moment loads, the shear resistant mechanism is explicitly decoupled into the base components-beam action and arch action. Then the overall behavior of a beam is explained in terms of the combination of these two base components. The gross compatibility condition between the deformations associated with the two actions is formulated utilizing the truss idealization together with some approximations. From this compatibility condition, the ratio of the shear contribution by the tied arch action is determined. The performance of the model is examined by a comparison with the experimental data in literatures. The results show that the proposed model can explain beam shear behavior in consistent way with clear physical significance.

• Structural Engineering and Mechanics
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• 제6권5호
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• pp.555-569
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• 1998

The reliability of antenna tower designed for a n-year design wind speed is determined by considering the variability of the strength of the component members and of the mean wind speed. For obtaining the n-year design wind speed, maximum annual wind speed is assumed to follow Gumbel Type-1 distribution. Following this distribution of the wind speed, the mean and standard deviation of stresses in each component member are worked out. The variability of the strength of members is defined by means of the nominal strength and a coefficient of variation. The probability of failure of the critical members of tower is determined by the first order second moment method (FOSM) of reliability analysis. Using the above method, the reliability against allowable stress failure of the critical members as well as the system reliabilities for a 75 m tall antenna tower, designed for n-year design wind speed, are presented.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1998년도 가을 학술발표회 논문집
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• pp.208-215
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• 1998

A stability problems of isotropic shells under pure bending is investigated based on the classical shells theory. The governing equations of stability problem presented by Donnell and Love, are developed and the solutions for the cylindrical shells are obtained by using Galerkin method. Bending moment is applied at the ends of the cylindrical shell as a from of distributed load in the shape of sine curve. For the isotropic materials, the result of the general purpose structural analysis program based on the finite element method are compared with the critical moment obtained from the classical shell theories. The critical loads for the cylindrical shells with various geometry can not be evaluated with a simple equation. However, accurate solutions for the stability problems of cylindrical shells can be obtained through the equilibrium equation developed in the study.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 춘계학술대회논문집
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• pp.513-517
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• 2004

This study aims to evaluate factors of floor structure influencing to the floor impact sound. For this reasons, we measured the vibration of floor and the floor impact sound in moment flame structure. The main results from this study are that slab area and thickness are critical factors of the floor impact sound and aspect ratio slab is not verified in flor impact sound.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2003년도 춘계 학술발표회논문집
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• pp.200-207
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• 2003

The seismic behaviors of steel moment connections are investigated based on the numerical analysis of the connections with US and Japanese typical details. The rupture index, representing the fracture potential, is used to evaluate the ductility of the connections at the critical location. The results show that the presence of a slab increases the beam strength, imposes constraint near the beam top flange, and consequently, induces concentrated deformation near the beam access hall, which reduces the ductility of the connection. The total deformation capacity of the connection depends not only on a beam but also on a column and panel zone.

• 한국기계가공학회지
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• 제12권1호
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• pp.110-116
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• 2013

Curvic coupling of mill turret should maintain disk weight and the cutting resistance which occurs the machining operation and must also have power transmission function. In order to improve machining operation range, the ejecting distance from curvic coupling to the disk must increase as much as possible. But moment is increased by the lack of capacity of the curvic coupling. Increase of moment is the cause of vibration/noise and degradation of machining performance not only stability problem. The manufacturer of mill turret has no the design information between the ejecting distance and the cutting resistance with safety of curvic coupling. Therefore this study describes a finite element analysis model of mill turret using ANSYS workbench. The structural analyses and modal analyses with varying of the ejecting distances and cutting resistances are performed. Finally the equation for relationship between the critical ejecting distance and the cutting resistance is defined under 5 of the safety factor for the maximum von-Mises stress at the curvic coupling.

• 영어영문학
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• 제64권1호
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• pp.25-37
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• 2018

The turning point is one of the more evocative concepts in the critic's arsenal, as it is equally suited to the evaluation and analysis of a given moment in one's day as to those of a historical event. But how does one recognize a turning point? As we find ourselves always "in the middest," both spatially and temporally, we inhabit sites that may be points at which many things may be seen to turn. Indeed, it is usually only possible to identify a turning point, as it were, from a distance, from the remove of space and time which allows for a sense of recognition, based in part on original context and in part of perceived effects. In this article, Robert T. Tally Jr. argues that the apprehension and interpretation of a turning point involves a fundamentally critical activity. Examining three models by which to understand the concept of the turning point-the swerve, the trope, and peripety (or the dialectical reversal)-Tally demonstrates how each represents a different way of seeing the turning point and its effects. Thus, the swerve is associated with a point of departure for a critical project; the trope is connected to continuous and sustained critical activity in the moment, and peripety enables a retrospective vision that, in turn, inform future research. Tally argues for the significance of the turning point in literary and cultural theory, and concludes that the identification, analysis, and interpretation of turning points is crucial to the project of criticism today.