• Coupled systems mechanics
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• v.7 no.6
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• pp.731-753
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• 2018

The recent seismic events have led to concerns on safety and vulnerability of Reinforced Concrete Moment Resisting Frame "RC-MRF" buildings. The seismic design demands are greatly dependent on the computational tools, the inherent assumptions and approximations introduced in the modeling process. Thus, it is essential to assess the relative importance of implementing different modeling approaches and investigate the computed response sensitivity to the corresponding modeling assumptions. Many parameters and assumptions are to be justified for generation effective and accurate structural models of RC-MRF buildings to simulate the lateral response and evaluate seismic design demands. So, the present study aims to develop reliable finite element model through many refinements in modeling the various structural components. The effect of finite element modeling assumptions, analysis methods and code provisions on seismic response demands for the structural design of RC-MRF buildings are investigated. where, a series of three-dimensional finite element models were created to study various approaches to quantitatively improve the accuracy of FE models of symmetric buildings located in active seismic zones. It is shown from results of the comparative analyses that the use of a calibrated frame model which was made up of line elements featuring rigid offsets manages to provide estimates that match best with estimates obtained from a much more rigorous modeling approach involving the use of shell elements.

• Nuclear Engineering and Technology
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• v.28 no.4
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• pp.423-430
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• 1996

The improved and advanced Annulus Gas System(AGS) has been developed for Wolsong 2 to satisfy the requirements of the regulatory body. The Atomic Energy Control Board(AECB) required a shorter detection time following a small leak from a pressure tube and/or calandria tube. This paper describes licensing requirements, functional requirements and detail design description for the AGS. The Wolsong unit No. 1 AGS was designed to operate as a stagnant system normally requiring only pressure regulation and having provisions for purging. no improved AGS involves the adoption of gas recirculation in AGS, duplication of dew point indicators with additional instrumentation and sampling provisions to prompt operator action. The improved system operates in the recirculation mode with continuous dew point measurement for leak detection. An AGS with improved detection instrumentation is provided.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.116-119
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• 2004

The use of higher strength materials frequently requires the change of design provisions. Following to the previous researches, high strength reinforcing bars have a weak point about the development and splice length. Based on the previous research about high relative rib area, bond strength between reinforcing bars and concrete can be improved by the control of rib height and spacing. But, the code provisions do not include these specific shape of reinforcing bars. So, the purpose of this paper is to determine the effect of relative rib area to the bond strength. This paper describes the experiment and analysis of 5 beam-spliced specimens containing D25 with relative rib areas ranging from 0.073 to 0.17. The test results are also analyzed to make a design formula about the calculation of splice length on the consideration of relative rib area.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.688-691
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• 2004

This study summarizes results of a research project aimed at investigating the inelastic rotation capacity of beam-column joints of reinforced concrete moment frames. A total of 28 specimens were classified as special moment frame connections based on the design and detailing requirements in the ACI 318-99 provisions. Then, the acceptance criteria, originally defined for steel moment frame connections in the AISC-97 Seismic Provisions, were used to evaluate the joint connections of concrete moment frames. Twenty seven out of 28 test specimens that satisfy the design requirements for special moment frame structures provided sufficient strength and are ductile up to a plastic rotation of $3\%$ without any major degradation in strength.

• Magazine of the Korea Concrete Institute
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• v.10 no.1
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• pp.10-19
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• 1998

• Magazine of the Korea Concrete Institute
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• v.13 no.3
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• pp.122-130
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• 2001

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.2
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• pp.437-446
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• 2014

In this study, the ultimate strengths of 13 slab-column joints and 51 torsional beams were evaluated to verify the validity of the strut-tie model approach presented in the companion paper. In addition, the design of the bridge pier subjected to multiple load combinations with longitudinal and lateral loads was conducted. The analysis results were compared with those by the provisions of BS 8110, ACI 318, and AASHTO-LRFD. The design results of the bridge pier were also compared with those by the provisions of ACI 318's sectional design method and AASHTO-LRFD's strut-tie model method.

• Fire Science and Engineering
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• v.23 no.2
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• pp.6-12
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• 2009

In this paper, provisions related with the seismic design and equipments of fire protection system are being considered. The provisions from various international codes on seismic design fire protection system were reviewed. The codes, reviewed are, Japanese code, NFPA guideline and Korean Code. It is noted that all the codes excepted to Korean Code consider earthquake effect to evaluate seismic forces and behaviors. But, korean provision are not covered in seismic response in all. A brief description on limitations in Korean Code is also presented.

• Structural Engineering and Mechanics
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• v.12 no.3
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• pp.249-266
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• 2001

Current seismic design provisions allow structures to deform into inelastic range during design level earthquakes since the chance to meet such event is quite rare. For this purpose, design base shear is defined in current seismic design provisions as the value of elastic seismic shear force divided by strength reduction factor, R (${\geq}1$). Strength reduction factor generally consists of four different factors, which can account for ductility capacity, overstrength, damping, and redundancy inherent in structures respectively. In this study, R factor is assumed to account for only the ductility rather than overstrength, damping, and redundancy. The R factor considering ductility is called "ductility factor" ($R_{\mu}$). This study proposes ductility factor with correction factor, C, which can account for dynamic P-${\Delta}$ effect. Correction factor, C is established as the functional form since it requires computational efforts and time for calculating this factor. From the statistical study using the results of nonlinear dynamic analysis for 40 earthquake ground motions (EQGM) it is shown that the dependence of C factor on structural period is weak, whereas C factor is strongly dependant on the change of ductility ratio and stability coefficient. To propose the functional form of C factor statistical study is carried out using 79,920 nonlinear dynamic analysis results for different combination of parameters and 40 EQGM.

• Wind and Structures
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• v.2 no.1
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• pp.1-23
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• 1999

Wind effects are critical considerations in the design of topside structures, overall structural systems, or both, depending on the water depth and type of offshore platform. The reliable design of these facilities for oil fields in regions of hostile environment can only be assured through better understanding of the environmental load effects and enhanced response prediction capabilities. This paper summarizes the analysis and performance of offshore platforms under extreme wind loads, including the quantification of wind load effects with focus on wind field characteristics, steady and unsteady loads, gust loading factors, application of wind tunnel tests, and the provisions of the American Petroleum Institute Recommended Practice 2A - Working Stress Design (API RP 2A-WSD) for the construction of offshore structures under the action of wind. A survey of the performance of platforms and satellite structures is provided, and failure mechanisms concerning different damage scenarios during Hurricane Andrew are examined. Guidelines and provisions for improving analysis and design of structures are addressed.