• Geomechanics and Engineering
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• 제6권3호
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• pp.293-320
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• 2014

In this study, in order to evaluate adequacy of considering local site effect, excluding soil-structure interaction (SSI) effects in inelastic dynamic analysis and design of mid-rise moment resisting building frames, three structural models including 5, 10, and 15 storey buildings are simulated in conjunction with two soil types with the shear wave velocities less than 600 m/s, representing soil classes $D_e$ and $E_e$ according to the classification of AS1170.4-2007 (Earthquake actions in Australia) having 30 m bedrock depth. Structural sections of the selected frames were designed according to AS3600:2009 (Australian Standard for Concrete Structures) after undertaking inelastic dynamic analysis under the influence of four different earthquake ground motions. Then the above mentioned frames were analysed under three different boundary conditions: (i) fixed base under direct influence of earthquake records; (ii) fixed base considering local site effect modifying the earthquake record only; and (iii) flexible-base (considering full soil-structure interaction). The results of the analyses in terms of base shears and structural drifts for the above mentioned boundary conditions are compared and discussed. It is concluded that the conventional inelastic design procedure by only including the local site effect excluding SSI cannot adequately guarantee the structural safety for mid-rise moment resisting buildings higher than 5 storeys resting on soft soil deposits.

• 한국구조물진단유지관리공학회 논문집
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• 제22권6호
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• pp.63-71
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• 2018

인장강도가 2,400 MPa인 강연선이 개발되어 콘크리트구조기준 및 KS 규격에 반영되었다. 고강도 프리스트레스트 강연선이 구조물에 적용되기 위해서는 그에 적합한 정착시스템이 함께 사용되어야 한다. 최근에 2,400 MPa 강연선 적용을 위한 포스트텐션 정착구의 개발이 진행되어왔으나, 성능평가에 대한 연구가 미비한 실정이다. 따라서 본 연구에서는 2,400 MPa 강연선을 적용한 포스트텐션 정착구 중 가장 활용도가 높은 9 가닥, 15 가닥, 19 가닥 정착구에 대하여 PTI의 Anchorage Design Zone에 의한 국소구역 구조검토를 실시하였고, ETAG013 및 KCI-PS101에 의한 하중전달성능평가를 수행하였다. 또한 비선형 수치해석을 통해 시험의 적절성을 분석하였다. 그 결과, 2,400 MPa 정착구는 국소구역의 구조성능을 만족하고, 하중전달성능 조건을 만족하는 것으로 나타났다.

• Structural Engineering and Mechanics
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• 제11권6호
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• pp.575-590
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• 2001

This paper presents a simplified method for the design and analysis of non-prestressed, partially prestressed, and fully prestressed concrete beams subjected to pure torsion. The proposed model relates the torsional strength to the concrete compressive strength and to the amounts of transverse and longitudinal reinforcement. To check the adequacy of this simple method, the calculated strength and mode of failure are checked against the experimental results of 17 prestressed concrete 66 reinforced concrete beam tests available in the literature, and very good agreement is found. The simplicity of the method is illustrated by two examples, one for design and another for analysis.

• 대한전기학회논문지:전력기술부문A
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• 제52권5호
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• pp.287-293
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• 2003

The deregulation and structural reform of power markets have started from the early 90s, which has brought about new studies on the new environment. Regardless the market structure, however, power systems need to be operated and planned in a stable and reliable manner. Therefore, decisions on proper amount of operating reserves and their reliable operations are very important. Up to now, the decision processes of operating reserves depend mainly on experiences of operators in Korea. When Korean power market comes under private management, operating reserves would influence power rate as well as power Quality, Therefore, it is time to prepare reasonable operating reserve standards in a systematic way for the new environment. This study suggests the proper operating reserve standards considering rules of the power market in Korea. To verify the adequacy of the proposed standards, stability and frequency characteristics of the Korean power system are analyzed as well.

• 대한가정학회지
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• 제37권6호
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• pp.77-96
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• 1999

The purpose of this study was to examine the effect of family-of-origin, personal and spousal characteristics, mediated by communication and problem-solving behavior, on marital quality and stability. On the basis of previous literature, the theoretical model was specified, estimated, and evaluated for adequacy of statistical fit for samples of 214 married women. Although the initial model was not supported by data, the revised model fitted the data adequately. Results of structural equation modeling indicated family-of-origin and communication behavior directly affected marital quality. However, the personal and spousal characteristics were linked with marital quality and stability only if they were mediated by communication and problemsolving behavior. Communication behavior was strongly related to marital quality and stability both directly and indirectly through problem-solving behavior. The model also showed marital quality can be an antecedent variable for marital stability. The findings of results is to generate more broad-minded thinking about how communication behavior, marital quality, and marital stability are interrelated.

• Structural Engineering and Mechanics
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• 제41권4호
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• pp.459-477
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• 2012

This paper attempts to determine the inclination of the compression strut within variable angle truss models for RC beams loaded in shear-flexure through a proposed semi-analytical approach. A truss unit is used to analyze a reinforced concrete beam, by the principle of virtual work under the truss analogy. The inclination of the compression strut is then theoretically derived. The concrete contribution is addressed by utilizing the compatibility condition within each truss unit. Comparisons are made between the predicted and published experimental results of the seventy one RC beams with respect to the shear strength and the inclined angle of the compression strut at this state to investigate the adequacy of the proposed semi-analytical approach.

• 대한조선학회 특별논문집
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• 대한조선학회 2008년도 특별논문집
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• pp.29-32
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• 2008

Hinged cross bar which is fitted for buyer's special item in cell guide of container vessels has an advantage of efficiency on container loading. In this paper, the main focus is to confirm the structural adequacy of hinged cross bar supporting structure in cell guide under the considered loading condition for container vessel.

• Nuclear Engineering and Technology
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• 제44권6호
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• pp.683-688
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• 2012

The structural integrity of mechanical components during several transients should be assured in the design stage. This requires a fatigue analysis including thermal and stress analyses. As an example, this study performs a fatigue analysis of the reactor pressure vessel of SMART during arbitrary transients. Using heat transfer coefficients determined based on the operating environments, a transient thermal analysis is performed and the results are applied to a finite element model along with the pressure to calculate the stresses. The total stress intensity range and cumulative fatigue usage factor are investigated to determine the adequacy of the design.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
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• pp.1297-1302
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• 2000

A literature review has been carried out to investigate why bridges have collapsed without warning. The reasons behind the collapses have been categorized into short and long term risks. It is thought that permanent monitoring systems which assess structural adequacy are more appropriate to long term risks. From the knowledge of the Korean bridge stock, its current problems and its likely future problems, it was considered that generally the most useful application for a permanent monitoring system is to monitor where chloride-induced corrosion either of the reinforcement or prestressing tendons is possible. A number of permanent monitoring systems currently in use on existing bridges which include some aspect of corrosion detection have been reviewed. The reasons as to why they are being used, what is being measured, what techniques are being used, and if they are deemed successful has been investigated. Based on these findings, and experimental programme has been constructed to investigate the accuracy, reliability and usefulness of various suitable techniques which could be included in a permanent monitoring system.

• Structural Engineering and Mechanics
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• 제38권3호
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• pp.283-300
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• 2011

A new conception of fundamental tasks in dynamics of the bridge-track-train systems (BTT), with the aim to evaluate moving load's models adequacy, has been developed. The 2D physical models of BTT systems, corresponding to the fundamental tasks, have been worked out taking into account one-way constraints between the moving unsprung masses and the track. A method for deriving the implicit equations of motion, governing vibrations of BTT systems' models, as well as algorithms for numerical integration of these equations, leading to the solutions of high accuracy and relatively short times of simulations, have been also developed. The derived equations and formulated algorithms constitute the basis for numerical simulation of vibrations of the considered systems.