• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.10a
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• pp.319-326
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• 2001

In this paper, 3-D frame design using refined plastic-hinge analysis accounting for local buckling is developed. This analysis accounts for material and geometric nonlinearities of the structural system and its component members. Moreover, the problem associated with conventional refined plastic-hinge analyses, which do not consider the degradation of the flexural strength caused by local buckling, is overcome. Efficient ways of assessing steel frame behavior including gradual yielding associated with residual stresses and flexure, second-order effect, and geometric imperfections are presented. In this study, a model consisting of the width-thickness ratio is used to account for local buckling. The proposed analysis is verified by the comparison of the LRFD results.

• KCI Concrete Journal
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• v.12 no.1
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• pp.3-16
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• 2000

A series of dynamic and static tests were conducted to observe the actual responses of a 1:5 scale 3-story reinforced concrete(RC) frame which was designed only for gravity loads. One of the major objectives of these experiments is to provide the calibration to the available static and dynamic inelastic analysis techniques. In this study, the experimental results were simulated by using a nonlinear analysis program for reinforced concrete frame, IDARC-2D. The evaluation of the degree of the simulation leads to the conclusion that while the global behaviors such as story drifts and shears can be in general simulated with the limited accuracy in the dynamic nonlinear analysis, it is rather easy and simple to get the fairly high level of accuracy in the prediction of global and local behaviors in the static nonlinear analysis by using IDARC-2D.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.6
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• pp.107-112
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• 1998

A great deal of time and effort are required to evaluate the safety and durability of a vehicle structure in the vehicle development stage. It is difficult to find the reasons for cracks which occur in the body and frame of a vehicle during tests. Recently computer aided engineering techniques have been utilized to solve the problems of safety and durability of vehicles. In this study, a dynamic stress analysis is performed on the frame of the vehicle by rigid and flexible multibody dynamics techniques. The result of the analysis is compared to that of the actual test. The full vehicle dynamic models for the rigid and flexible bodies are developed by DADS package. The modal coordinate system is used to save time for the dynamic stress analysis. The flexible multibody dynamic models have 12 normal modes considering the flexibility of the frame. Dynamic stresses arc calculated by relating the stress influence coefficients and the applied forces.

• Steel and Composite Structures
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• v.30 no.3
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• pp.253-269
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• 2019

This paper investigates the effects of the tensile catenary action on dynamic increase factor (DIF) in the nonlinear static analysis for progressive collapse of steel-frame buildings. Numerical analyses were performed to verify the accuracy of the empirical and analytical expressions proposed in the literature in cases where the catenary action is activated. For this purpose, nonlinear static and dynamic analyses of a series of steel moment frame buildings with a different number of spans and stories were carried out following the alternate path method. Different column removal scenarios were considered as separate load cases. The dynamic increase factor that approximately compensates for the dynamic effects in the nonlinear static analysis was selected so to match results from the nonlinear dynamic analysis. The study results showed that the many expressions in literature may not work in cases where the catenary stage is fully developed.

• Korean journal of communication and information
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• v.41
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• pp.232-267
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• 2008

This study is a comparative analysis of news frames between Chosunilbo and Hankyereh which have shown contrastive political attitude. The coverage of two political scandal, the Prime Minister Lee Haechan's golf happening and an Assemblyman of opposition party Choi Yeonhee's sexual harassment were analysed. The two political scandals were occurred one after the other and had some similarities. But two newspapers showed very contrastive frame on the two political scandals. On the Prime Minister Lee's scandal Chosunilbo showed politicizing frame, lobby golf frame, immorality frame, resignation frame. In contrast Hankyereh used depoliticization frame and human error frame. On the Assemblyman Choi's scandal Hankyereh showed politicizing frame, personal responsibility frame, immorality frame, resignation frame. But Chosunilbo used social responsibility frame and human error frame. In conclusion two newspapers showed very contrastive coverage according to the respective political attitude.

• Korean journal of communication and information
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• v.43
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• pp.117-151
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• 2008

This paper regards former Samsung lawyer Kim Yong-Chul's action of claiming Samsung Group's slush fund as typical Whistle-Blowing from inside. News frames in KBS, SBS TV were examined through comparative analysis. In formal feature, 'episodic news frame' hold an absolute majority in both stations. From news sources, the group of whistle-blower such as lawyer Kim Yong-Chul and civic groups was confronted with Samsung and state authorities including the Prosecutor, financial agencies. Analysis on the theme of news coverages demonstrated 5 frames: 'public announcing frame', 'news of conflict frame' 'demanding a close inquiry frame', 'declaration of conscience frame', 'causing social upheaval frame', Analysis result shows that 'public announcing frame' was most frequently used in reporting and there was distinction between KBS and SBS in 'declaration of conscience frame' and 'causing social upheaval frame'. Relatively KBS preferred 'declaration of conscience frame' and SBS would use 'causing social upheaval frame', from which reciprocal relation as media ownership could be analogized. Both media tend to make light of in-depth news coverages on structural issues or essential settlement and it is shown that both stations treated this situation with intriguing audiences as stressing sensitive parts in this event. Follow-up of changing process of 'declaration of conscience frame' through diachronic analysis on framing informs that additional exposure of 'Lee Yong Chul', former secretary in Nov 19, 2007 influenced increasing of frequency of using 'declaration of conscience frame'. However, news reporting on whistle-blower in KBS and SBS generally adheres to passive attitude of following changes in the surroundings rather than playing an active role in improving social recognition on whistle-blowing, which can induce to the spread of negative feature on it. Thus it is assumed that terrestial television broadcasting should regard whistle-blowing as contradiction in social structures and active depth reporting seems to be neded for improving social recognition on whistle-blowing.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.745-746
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• 2009

• Earthquakes and Structures
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• v.8 no.5
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• pp.1255-1276
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• 2015

The importance of considering soil-structure interaction effect in the analysis and design of RC frame buildings is increasingly recognized but still not penetrated to the grass root level owing to various complexities involved. It is well established fact that the soil-structure interaction effect considerably influence the design of multi-storey buildings subjected to lateral seismic loads. The shear walls are often provided in such buildings to increase the lateral stability to resist seismic lateral loads. In the present work, the linear soil-structure analysis of a G+5 storey RC shear wall building frame resting on isolated column footings and supported by deformable soil is presented. The finite element modelling and analysis is carried out using ANSYS software under normal loads as well as under seismic loads. Various load combinations are considered as per IS-1893 (Part-1):2002. The interaction analysis is carried out with and without shear wall to investigate the effect of inclusion of shear wall on the total and differential settlements in the footings due to deformations in the soil mass. The frame and soil mass both are considered to behave in linear elastic manner. It is observed that the soil-structure interaction effect causes significant total and differential settlements in the footings. Maximum total settlement in footings occurs under vertical loads and inner footings settle more than outer footings creating a saucer shaped settlement profile of the footings. Each combination of seismic loads causes maximum differential settlement in one or more footings. Presence of shear wall decreases pulling/pushing effect of seismic forces on footings resulting in more stability to the structures.

• Journal of Korean Association for Spatial Structures
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• v.11 no.3
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• pp.95-103
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• 2011

Among structural systems for complex-shaped tall buildings, diagrid system is widely used because of its structural efficiency and beauty of form. Recently, mega frame is favorably employed as a suitable structural system for skyscrapers because this structural system has sufficient stiffness against the lateral forces by combination of mega members which consist of many columns and girders. Diagrid mega frame system is expected to be promising structural system for future super tall buildings. However, it takes tremendous analysis times and engineer's efforts to predict the structural behavior of tall buildings applied with diagrid mega frame system because the diagrid mega frame structure has significant numbers of elements and nodes. Therefore, efficient analytical method for all buildings applied with diagrid mega frame system has been proposed in this study to reduce the efforts and time required for the analysis and design of diagrid mega frame structure. To this end, an efficient modelling technique using the characteristics of diagrid mega frame structures and an efficient analytical model using minimal DOFs by the matrix condensation method were proposed in this study. Based on the analysis of an example structure, the effectiveness and accuracy of the proposed method have been verified by the comparison between the results of the proposed method and the conventional method.

• Korean Architects
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• no.11 s.82
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• pp.22-25
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• 1975

The aim of this study is the introduction of simplified method for the design stress analysis of multi-span gable frame structures with crane supports. Under the author's assumptions made previously for the same structures of single span, simplified stress analysis and exact computer analysis are excuted for some multi-span sample structures. Comparing the results of both stress analysis and with some modifications, a feasible simplified method for the design stress analysis of multi-span gable frame structures with crane supports is established.