• 건축구조
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• v.12 no.1
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• pp.48-55
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• 2005

• Journal of the Computational Structural Engineering Institute of Korea
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• v.13 no.1
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• pp.105-113
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• 2000

Seismic behavior of 3-dimensional setback structures showing abrupt reductions of the floor size within the structure height and the effect of in-plane deformations of floor slabs on the seismic behavior of those structures are investigated. To find out general seismic behavior of 3-dimensional setback structures two parameters, level of setback(L/sub s/) and degree of setback(R/sub s/) are used. Analysis results obtained from forty eight setback structures show that a sudden change in story shear near setback level is occurred for irregular setback structures. The effect of in-plane deformation of floor slabs on the seismic behavior of setback structures is greatly influenced by the arrangement of lateral load resisting elements and it is more pronounced for frame-shear wall system showing large difference in stiffness among the lateral load resisting elements. The in-plane deformation of floor slabs results in reduced base shear, especially for FW-type structures with L/sub s/=1.0. Also, it brings about reduced story shear for the lateral load resisting element with shear wall and increase in story shear lot the lateral load resisting element without shear wall. The in-plane deformation of floor slabs at the base portion and/or tower portion due to difference in stiffness among the lateral load resisting elements brings about increment of floor displacements at all floor level.

• Journal of the Korea Concrete Institute
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• v.20 no.1
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• pp.35-41
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• 2008

In general, flat plate systems have been used as a gravity load resisting system (GLRS) in building. Thus, this system should be constructed with lateral force resisting system (LFRS) such as shear walls and brace frames. GLRS should retain the ability to undergo the lateral drift associated with the LFRS without loss of gravity load carrying capacity. And flat plate system can be designed LFRS as ordinary moment frame with the special details. Thus, flat plate system designed as GLRS or LFRS should be considered internal forces (e.g., unbalanced moments) and lateral deformation generated in vicinity of slab joints render the system more susceptible to punching shear. ACI 318 (2005) allows the direct design method, equivalent frame method under gravity loads and allows the finite-element models, effective beam width models, and equivalent frame models under lateral loads. These analysis methods can produce widely different result, and each has advantage and disadvantages. Thus, it is sometimes difficult for a designer to select an appropriate analysis method and interpret the results for design purposes. This study is to help designer selecting analysis method for flat plate system and to verify practicality of the modified equivalent frame method under lateral loads. This study compared internal force and drift obtained from frame methods with those obtained from finite element method under gravity and lateral loads. For this purposes, 7 story building is considered. Also, the accuracy of these models is verified by comparing analysis results using frame methods with published experimental results of NRC slab.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.4
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• pp.435-442
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• 2007

Since the Ronan Point apartment collapsed in 1968, researches on the progressive collapse have been intermittently conducted, and the collapse of the World Trade Center twin towers made the researches active again. In the United States guidelines such as GSA (2003) and DoD (2005) were provided for design and analysis of building structures against the progressive collapse. In this study the progressive collapse-resisting capacity of steel moment resisting frames designed by KBC-2005 was investigated using linear elastic static analysis and linear dynamic analysis procedures suggested in the guidelines. The results showed that in accordance with the GSA guideline the moment frame designed only for gravity load turned out to be vulnerable to the progressive collapse, whereas the lateral load resisting frame designed for earthquake load satisfied the criteria for progressive collapse. However both systems sailed to satisfy the criteria of the DoD-2005 guideline.

• Journal of the Korea institute for structural maintenance and inspection
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• v.7 no.4
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• pp.201-208
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• 2003

The Hybrid Wall System(HWS) building composed of center core reinforced concrete walls and exterior steel frame has open space around the center core walls. It is necessary to develop design methodologies for the HWS building that the coupled shear walls withstand the most of lateral load and expect the most energy dissipation at the coupling beams and at wall foots. Major factors considered in this paper are connection type of coupling beams and scale of story. The studies of the system are investigated in terms of shear force, overturning moment, maximum lateral displacement, story drift ratio, and dynamical characteristics under the action of vertical and lateral forces such as wind and seismic loads.

• Construction Engineering and Management
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• v.21 no.5
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• pp.27-31
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• 2020

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.6
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• pp.513-523
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• 2012

The objective of this research is to examine how the lateral resisting system of selected prototypes are affected by seismic zone effect and shape irregularity on its seismic performance. The lateral resisting systems are divided into the three types, diagrid, braced tube, and outrigger system. The prototype models were assumed to be located in LA, a high-seismicity region, and in Boston, a low-seismicity region. The shape irregularity was classified with rotated angle of plane, $0^{\circ}$, $1^{\circ}$, $2^{\circ}$. This study performed two parts of analyses, Linear Response and Non-Linear Response History(NLRH) analysis. The Linear Response analysis was used to check the displacement at the top and natural period of models. NLRH analysis was conducted to invest base shear and story drift ratio of buildings. As results, the displacement of roof and natural period of three structural systems increase as the building stiffness reduces due to the changes in rotation angle of the plane. Also, the base shear is diminished by the same reason. The result of NLRH, the story drift ratio, that was subject to Maximum Considered Earthquake(MCE) satisfied 0.045, a recommended limit according to Tall Building Initiative(TBI).

• Journal of Korean Society of Steel Construction
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• v.21 no.4
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• pp.375-384
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• 2009

The application of the diagrid structural system has increased of late, but cyclic loadings such as winds and earthquakes cannot be fully understood through only an analytical study due to the difficulty of considering its welding property. In this study, diagrid nodes that had been scaled down to 1/5 of their full sizes were tested to find out their structural behavior under seismic or wind loads. Four specimens were used with five parameters, including the welding method and the design details. Cyclic loading tests were carried out, where a tensile load was applied to one brace member and a compression load to the other. The major failure modes in the tests were only failure of bending with tensile stress and tension failure. The welding method and the design details had no effect on the initial stiffness and yielding stress but play a significant role in the failure mode and energy dissipation, respectively.

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.1
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• pp.1-9
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• 2013

In this study of Eccentric Braced Frames have identified the following target eccentricity on the length of the inelastic behavior of the reaction by calculating the correction factor by comparing it to the value suggested by the earthquake provided material for the rational design aims to There are. As a variable-length V-braced frame analysis model stations were set up. Eccentricity faults in the model according to the length stiffness ratio, the maximum amount of energy dissipation were analyzed base shear and multi-layered model of the reaction from the eccentricity correction factor calculated on the length of the building standards proposed by KBC 2009 in response eccentricity correction factor calculated from The length varies. does not have the same response modification factor was confirmed.

• Journal of the Korean Geotechnical Society
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• v.24 no.8
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• pp.137-148
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• 2008

In this study, 28 earthquake records with magnitudes from 5.3 to 7.9 are selected for dynamic analysis in order to assess applicability of the earthquakes for domestic seismic design. The assessment is performed using the seismic spectrum analysis of energy and acceleration. Based on results of the analysis, four acceleration time histories, which satisfy the Korean design standard response spectrum, are proposed. From the dynamic analysis using earthquake magnitudes from 6.4 to 7.9, it is found that horizontal displacements corresponding to earthquake magnitudes greater than 7 are two times larger than those with magnitude 6.5. Therefore, it can be stated that use of strong earthquakes, such as Miyagiken-ken-oki earthquake (Ofunato, $M_{JMA}=7.4$) and Tokachi-oki earthquake (Hachinohe, $M_{JMA}=7.9$), for the seismic design in Korea is not applicable, and may prove to be excessively conservative due to overestimated seismic force. From the dynamic analyses using the proposed acceleration time histories, effects of caisson quay wall dimension and the subsoil condition are investigated as well. The simplified design charts to evaluate horizontal displacements of caisson quay wall are also proposed based on earthquake magnitude 6.5 that is appropriate in Korea.