• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.11
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• pp.1773-1778
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• 2010

To evaluate the structural integrity of the main cooling-water pump of a nuclear power plant under different seismic conditions, the seismic analysis was performed in accordance with IEEE-STD-344 code. The finite element computer program, ANSYS, was used to perform both mode frequency analysis and response spectrum analysis for the pump assembly. The natural frequencies, the mode shapes, and the mode participation factors were obtained from the results of the mode frequency analysis. The stresses resulting from various loadings and their combinations were within the allowable limits specified in the above-mentioned IEEE code. The results of the seismic evaluation fully satisfied the structural acceptance criteria of the IEEE code. Thus, it was proved that the structural integrity of the pump assembly was satisfactory.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1500-1505
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• 2008

To evaluate the structural integrity of the nuclear seismic category IIA bellows seal 2" globe valve under the seismic service conditions the seismic analysis was performed in accordance with ASME, section III, ND-3500, 1989 edition. The finite element computer program, ANSYS, Version 10.0, is used to perform both a mode frequency analysis and an equivalent static seismic analysis of the valve assembly. The mode frequency analysis results show the fundamental natural frequency is greater than 33 Hz and does not exist in seismic range, thus justifying the use of the static analysis. The stresses resulted from various loadings and their combinations are within the allowable limits specified in the above mentioned ASME code. The results of the seismic evaluation fully satisfied the structural acceptance criteria of the ASME code. Accordingly the structural integrity on the globe valve was proved.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.04a
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• pp.395-399
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• 2010

강구조 부재의 내화성능평가를 위한 비재하가열시험은 강재 허용온도로 평가되고 있으나, 강재의 허용온도 설정은 H형강 부재의 최대하중로 평가되는 한계용도와 고온에서의 강소재의 허용응력도 능력으로 설정되었으므로 실지 작용되는 강구조 부재의 하중조건과 다양한 부재의 종류 등의 관점에서 허용온도의 적용은 다소 불합리한 점이 있다고 판단된다. 따라서 본 연구에서는 강구조 건축물에서의 부재에 작용하는 하중에 따른 내화성능의 차이를 보이고 이에 따른 합리적인 내화성능 평가방법을 제안하고자 한다.

• 한국문화재보존과학회:학술대회논문집
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• 2005.11a
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• pp.142-147
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• 2005

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.322-325
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• 2010

철강 플랜트 주요 설비인 전로를 지지하는 장치의 접합부 강도설계를 위해 작용하중은 해석적인 방법으로 신뢰성 있게 계산하였고, 정적하중에 의한 응력은 ASME 규정에 따른 허용응력으로 평가하였다. 한편 피로설계 측면에서는 전로와 같은 대형 용접구조물은 강도상 취약부인 용접부에서 다양한 용접비드 형상에 따라 국부응력이 크게 달라지므로 설계단계에서 피로수명 평가에 어려움이 있었다. 따라서 전로 지지장치 접합부 피로설계는 설계단계에서 피로수명을 평가하는 실용적이고 안전측 방법으로 알려진 Hot Spot 응력을 사용하고 공신력을 갖는 설계규정인 ASME와 영국 PD 5500 절차에 의해 평가하였다. 평가결과 두 규정 모두 안전측에서 평가되는 것을 확인할 수 있었고 이 방법은 피로하중이 지배적인 대형구조물의 설계단계에서 유용한 방법으로 활용할 수 있으리라 판단된다.

• Journal of the Korean GEO-environmental Society
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• v.20 no.11
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• pp.11-22
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• 2019

Limit state design (LSD) and allowable stress design (ASD) are two main types of soil nailing design methodologies. In the LSD method, stability is determined by applying individual coefficients to ground strength, working load and etc. The ASD method calculates the safety factor and compares it with the minimum safety factor to determine the stability. The global design trend of soil nailing system is changing from the ASD method to the LSD method. The design method in Korea still adopts the ASD philosophy while others mostly do the limit state design. In this study, four soil nail design methods, 'FHWA GEC 7' in U.S. (2015), 'Clouterre' in France (1991), 'Soil nailing - best practice guidance' in U.K. (2005), 'Geoguide 7' in Hongkong (2008), and 'Design guide for slope in construction work' in Korea (2016) were applied to the evaluation of the stability and the results were analyzed comparatively in brief. It is revealed that the design method of 'the overall stability of soil nail walls' in Korea is the most conservative and next those by FHWA, Clouterre and CIRIA become more conservative in order. However, the difference of results obtained from FHWA and Clouterre is negligible. Also, this study found out that efforts to improve domestic design criterion are needed.

• Korean Architects
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• no.3 s.156
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• pp.53-59
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• 1982

• Journal of Korean Society of Steel Construction
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• v.28 no.4
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• pp.263-270
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• 2016

Corrosion resistance steel has been widely used for port and offshore structures exposed to harsh coastal and oceanic environments, due to lower corrosion rate. New higher strength corrosion resistance steel tubes named STKM500 in KS D 3300 were recently developed by domestic technology and expected to replace foreign ASTM A690 steel. In this study, tensile test results are included to show higher yield and tensile strength of STKM500. Then, buckling test results obtained from 2m, 6m, and 12m steel tubes are demonstrated, based on which an allowable axial compressive stress curve for STKM500 steel tubes is suggested.

• Journal of Welding and Joining
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• v.12 no.1
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• pp.102-115
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• 1994

This paper is to evaluate the fatigue strength of lap joints of materials applied to LNG carrier cargo containment of GAZ-TRANSPORT(GT) type, which was welded by manual and automatic TIG welding process. The thicknesses of lapped members were 1.5mm/1.5mm or 1.5mm/0.7mm in Invar to Invar joint, and 1.5mm/8.0mm in Invar to stainless steel joint, respectively. These lap joints were mainly applied to the membrance fabrication of GT-LNG carrier. Fatigue tests of Invar/Inar lap joints were conducted under the stress ratio R=0 at room temperature. The effect of mean stress and cumulative fatigue damage on the allowable stress of Invar lap joint was evaluated on the basis of test results. Fatigue test was also conducted on Inver/Stainless steel lap joints welded by automatic TIG process without filler metals. The fatigue test of the joint was carried out under the same conditions as those of Invar/invar lap joints. The fatigue strength of the joint welded without filler metal was comparable to those welded with filler metal quoted from reference. The fatigue strength of Invar/stainless steel lap joint was only dependent on the lap throat thickness, and not on the welding process. Based on test results, the applicability of TIG welding process without filler metal in Invar/stainless steel lap joint was reviewed by controlling welding variables to assure the valid throat thickness of lap joints.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.4
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• pp.9-17
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• 2012

In the previous research, allowable compressive stress was analyzed based on strength theory, in which primary effect factors on the allowable compressive stress, such as eccentricity ratio, section type, section size, prestress and self-weight moment, were considered. As its results, allowable compressive stress equations were proposed. As a series of the previous research, this paper presents an experimental study on the prestress at transfer of pre-tensioned members with different eccentricity ratios. The results shows that ACI318-08 and EC2-02 are unconservative for the members under low eccentricity ratios, and they are conservative for the members under high eccentricity ratios. Compared to the code provisions, the results indicates that the proposed equation reasonably well evaluates the allowable compressive stresses for those with different eccentricity ratios.