• Journal of the Earthquake Engineering Society of Korea
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• v.16 no.6
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• pp.13-20
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• 2012

In this study, 5-story structures were designed in accordance with KBC2009 for inelastic time history analysis of RC IMRF. Bending moment-curvature relationship for beam and column was identified with fiber model and bending moment-rotation relationship for beam-column joint was calculated with simple and unified joint shear behavior model and moment equilibrium relationship for the joint. The hysteretic behavior was simulated with three-parameter model suggested in IDARC program. The analytical results showed that the inelastic shear behavior of the joint could be neglected in the structural design for seismic design category C but the structure of category D did not satisfy the criteria of FEMA 356 for collapse prevention performance level.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2000.10a
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• pp.222-229
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• 2000

The purpose of this study is to evaluate and make a comparison between the Ordinary Moment Resisting Frames using different analytical joint model for the Nonlinear response. For this purpose, 3-story structure was designed according to NEHRP 1994 Guidelines. And the center-line dimension model and model considering panel zone were used as analytical model for the structure. Nonlinear Static Procedure and Nonlinear Dynamic Procedure were used to evaluate seismic capacities and demands. The limitation in FEMA 273 was used as the variable number to predicte seismic demands of OMRFs. This analytical studies were performed with DRAIN-2DX modified by Shan Shi. Using the above results, the performance evaluation and seismic demands of OMRFs shall be performed. Finally NSP and NDP shall be compared.

• Journal of the Earthquake Engineering Society of Korea
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• v.4 no.4
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• pp.105-110
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• 2000

중약진 지역으로 분류되고 있는 대만에서 1999년에 발생된 예상치 못한 막대한 경제적 피해와 사상자를 기록하였다. 대만과 마찬가가지로 중약진지역으로 분류되는 우리나라에서도 지진발생시 많은 문제발생이 예상됨에 따라 기존건물의 내진성능평가의 필요성의 인식하게 되었다. 본 연구에서는 미국과 일본에서 이미 적용되고 있는 기존 건축물의 내진성능 평가 기법을 분석하고 이를 3층 규모의 모멘트 골조 건물에 적용하여 평가해 보았다. 평가는 일본건축방재협회에는 철근콘크리트 구조물의 내진성능평가 규준을 적용하였다.

• Journal of the Earthquake Engineering Society of Korea
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• v.20 no.2
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• pp.91-101
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• 2016

This study is the compared seismic performance that are difference between the performance of structures on various site classes and beam-column connection. this analysis model was designed the previous earthquake load. To compare the performance levels of the structure was subjected to nonlinear static and nonlinear dynamic analysis. Nonlinear analysis was used to The Perform 3D program. Nonlinear static analysis was compared with the performance point and Nonlinear dynamic analysis was compared the drift ratio(%). Analysis results, the soft site class of the displacement was more increase than rock site classes of the displacement. Also The smaller the displacement was increased beam-column connection stiffness.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2006.03a
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• pp.209-216
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• 2006

For evaluation of building performance, a nonlinear dynamic capacity of the building is a key parameter. In this study, an reinforced concrete special moment resisting frame building was chosen to study the process of determining the nonlinear dynamic capacity. The building, which was designed by IBC 2003 representing new codes, was composed of special moment resisting frames in the perimeter and internal frames inside the building. The capacity, which is inter-story drift capacity, consists of two categories, local and global collapses. Global collapse capacity was determined by incremental dynamic analysis. Local collapse capacity was determined by the same method except for utilizing damage index. In audition to this, it was also investigated that the effect of including internal frames designed by gravity load in the analysis. Results showed that the damage index is a useful tool for determining local collapse. Furthermore, including the internal frames with special frames in the analysis is very important in determining the capacity of a building so both must be considered at the same time.

• Journal of Korean Society of Steel Construction
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• v.14 no.4
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• pp.557-566
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• 2002

This paper summarized the results of a full-scale cyclic seismic testing on four reduced beam section (RBS) steel moment connections. Specifically, these tests addressed a bolted web versus a welded web connection and strong versus medium panel zone (PZ) strength as key test variables. Specimens with medium PZ strength were designed to promote balanced energy dissipation from both PZ and RBS regions, in order to reduce the requirement for expensive doubler plates. Both strong and medium PZ specimens with welded web connection were able to provide sufficient connection rotation capacity required of special moment-resisting frames. On the other hand, specimens with bolted web connection performed poorly due to premature brittle fracture of the beam flange at the weld access hole. Unlike the case of web-welded specimens, specimens with cheaper bolted web connection could not transfer the actual plastic moment of the original (or unreduced) beam section to the column. No fracture occurred within the beam groove welds of any connection in this testing program. If fracture within the beam flange groove weld is avoided by using quality welding procedure as in this study, the fracture issue tends to move into the beam flange base metal at the weld access hole. Supporting analytical study was also conducted in order to understand the observed base metal fracture from the engineering mechanics perspective.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.4
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• pp.351-359
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• 2015

In order to exactly evaluate the seismic collapse capacity of a structure, probabilistic approach is required by considering uncertainties related to its structural properties and ground motion. Regardless of the types of uncertainties, they influence on the seismic response of a structures and their effects are required to be estimated. An incremental dynamic analysis(IDA) is useful to investigate uncertainty-propagation due to ground motion. In this study, a 3-story steel moment-resisting frame is selected for a prototype frame and analyzed using the IDA. The uncertainty-propagation is assessed with categorized parameters representing epistemic uncertainties, such as the seismic weight, the inherent damping, the yield strength, and the elastic modulus. To do this, the influence of the uncertainty-propagation to the seismic collapse capacity of the prototype frame is probabilistically evaluated using the incremental dynamic analyses based on the Monte-Carlo simulation sampling with the Latin hypercube method. Of various parameters related to epistemic uncertainty-propagation, the inherent damping is investigated to be the most influential parameter on the seismic collapse capacity of the prototype frame.

• Journal of Korean Society of Steel Construction
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• v.23 no.3
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• pp.337-347
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• 2011

In this study, seismic resistance of concrete encased U-shaped steel beam-to-steel H-shaped column connections was evaluated. Three specimens of the beam-to-column connection were tested under cyclic loading. The composite beam was integrated with concrete slab using studs. Re-bars for negative moment were placed in the slab. The primary test parameter was the details of the connections, which are strengthening and weakening strategies for the beam end and the degree of composite action. The depth of the composite beams was 600mm including the slab thickness. The steel beam and the re-bars in the slab were weld-connected to the steel column. For the strengthening strategy, cover plates were weld-connected to the bottom and top flanges of the steel beam. For the weakening strategy, a void using styrofoam box was located inside the core concrete at the potential plastic hinge zone. The test results showed that the fully composite specimens exhibited good strength, deformation, and energy dissipation capacities. The deformation capacity of the beam exceeded 4% rotation angle, which is the requirement for the Special Moment Frame.

• Journal of Korean Society of Steel Construction
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• v.26 no.4
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• pp.263-275
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• 2014

In this study, connection of steel reinforced concrete(SRC) column and composite beam which consists of H-section and U-section members were tested under cyclic loading. An essential point of the composite beam is the structural performance of welded joint between the H-section and the U-section members. To improve the structural performance of joint of two beam members, vertical stiffeners, trapezoidal stiffeners, and top bars were used. Five full-scaled specimens were designed to study the effect of a number of parameters on cyclic performance of connections such as H-section beam size($H-500{\times}200{\times}10{\times}16$, $H-600{\times}200{\times}11{\times}17$), the presence of stiffeners and top bars, and the presence of no weld access hole(WAH) method. Based on the test results, deformation capacity of the specimens with H-500 series beam and H-600 series beam were 4% and 3% rotation angle, which is the requirement for the Special Moment Frame and Intermediate Moment Frame(IMF), respectively. Test result showed that deformation capacity of connection with stiffeners and top bars is greater than that of connection without stiffeners and top bars. Finally, energy dissipation capacity and strain profile of specimens were summarized.

• Journal of the Earthquake Engineering Society of Korea
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• v.12 no.5
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• pp.47-56
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• 2008

This study was performed to evaluate the effect of Response modification factors (R-factor) in 3-, 9- and 20- story steel Moment Resisting Frame (MRF) buildings. Each structure was designed using a R-factor of 8, as tabulated in the 2000 International Building Code provision (IBC 2000) and Korea Building Code (KBC) 2008. In order to evaluate the maximum and minimum performance expected for such structures, an upper bound and lower bound design were adopted for each model. Next, each analytical model was designed using different R-factors (8, 9, 10, 11, 12) and four different structural periods with the original fundamental period. For a detailed case study, a total of 150 analytical models were subjected to 20 ground motions representing a hazard level with a 2% probability of being exceeded in 50 years. In order to evaluate the performance of the structures, static push-over and non-linear time history analysis (NTHA) were performed, and displacement ductility demand was investigated to consider the ductility capacity of the structures. The results show that the dynamic behaviors for the 3- and 9-story buildings are relatively stable and conservative, while the 20-story buildings show a large displacement ductility demand due to dynamic instability factors. (e.g. P-delta effect and high mode effect)