• Journal of the Korean Society of Hazard Mitigation
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• v.6 no.3 s.22
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• pp.9-16
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• 2006

In structural health monitoring, the safety of structural members are assessed by the level of stress measured by various strain sensors based on different sensing mechanisms. Since most existing strain sensors used for health monitoring system can cover a relatively small range of structural members, it is very difficult to measure the maximum value of the member subjected to varying amount and types of loads with those point sensors. The reliability of assessed safety of a member may be improved by increasing the number of sensors. It may not be also realistic to increase the number of sensors to overcome these drawbacks. In this paper, a stress measuring method for beam-column members is developed by estimating the maximum stress based on the average strains obtained from long gauge sensor. The average strain from long gage fiber optic sensor is transformed into the maximum strain by multiplication of the modification factor derived in this research.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4A
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• pp.465-474
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• 2008

Generally design of frame structures composed of beam-column member is accomplished by stability evaluation of each member considering the effective buckling length. This study selects a member of the smallest non-dimension slenderness ratio using the buckling eigenvalue calculated by the elastic buckling eigen-value analysis and axial force of the each member, and decides the initial deflection quantity reflected geometric and material nonlinearities from a suggested equation on the base of standard strength curve of Korea Bridge Design Code. Second-order elastic analysis applying the initial deflection is executed and the stability of each member is evaluated and decides ultimate strength. Through examples of eight-stories and four-stories plane frame structures, the evaluation of the stability is compared with the existing method and ultimate strength of the suggested method is compared with ultimate strength by the nonlinear inelastic analysis. Through these procedures, the increasing of effective buckling length by elastic buckling eigenvalue analysis is prevented from a new design method that considers initial imperfections. And the validity of this method is proved.

• Journal of the Korea Institute of Building Construction
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• v.23 no.6
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• pp.715-726
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• 2023

This study suggested that protective panels should be installed as sacrificial members as a safety design method for structures with potential explosions such as hydrogen charging stations to minimize direct damage to the structure and have resilience. To this end, the focus of the experiment is on quantitatively evaluating the impact of the structure when the protection panel is installed closely or spaced apart from the structure in a high-speed collision situation of the projectile. The experimental design used steel plates instead of concrete structural members mainly used in the past for excellent reproducibility, and the impact of structural members was compared and analyzed through deformation differences on the back of the steel plate. In addition, the impact of changes in the physical properties of the elastic body used as a separation material for the protective member and the difference in shock wave transmission time according to the protective member and the elastic body on the structural member was investigated.

• Proceeding of KASS Symposium
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• 2008.05a
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• pp.37-42
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• 2008

Cable member in structure is tension systems in which the load carrying members transmit loads to support system by tensile stress with no compression or flexure allowed. Cable system have been widely used large span structure roof, air-supported structure, prestressed membrane, cable network roof, suspension structures, guyed tower, ocean platforms, suspension bridges. Cable member can transmit loads by the edge connected system such as socket, swaging, mechanical splice sleave, clip, wedge, loop splice etc. This study will shown an experimental results on the strength of connection socket of cables. In the results of experiment, most of cable connection specimen occurred the failure at the connection socket part before the cable arrived at tensile failure load.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.4
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• pp.363-372
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• 2012

In this study, a new information-based hybrid modeling framework is proposed. In the hybrid framework, a conventional mathematical model is complemented by the informational methods. The basic premise of the proposed hybrid methodology is that not all features of system response are amenable to mathematical modeling, hence considering informational alternatives. This may be because (i) the underlying theory is not available or not sufficiently developed, or (ii) the existing theory is too complex and therefore not suitable for modeling within building frame analysis. The role of informational methods is to model aspects that the mathematical model leaves out. Autoprogressive algorithm and self-learning simulation extract the missing aspects from a system response. In a hybrid framework, experimental data is an integral part of modeling, rather than being used strictly for validation processes. The potential of the hybrid methodology is illustrated through modeling complex hysteretic behavior of beam-to-column connections.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.3
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• pp.100-109
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• 2021

This study was examined the tensile strength change of a circular tubular member with artificial sectional damage on its surface to consider surface sectional damage by corrosion. The tensile strength tests were conducted using circular tubular specimens with artificial sectional damage considering sectional damaged height and width on its surface according to the corrosion level. From the tensile strength test results, it is confirmed that tensile strength of the circular tubular specimens was affected by the damaged circumference (damaged width), not damaged length (damaged height) and their tensile failures were appeared at the minimum section of the artificial sectional damage part. Nonlinear finite-element analyses were conducted considering equivalent sectional damage effect on sectional damaged part in tensile specimens to examine the change in the tensile strength of tubular specimens with artificial sectional damage since it is difficult to estimate the sectional damaged surface condition of the specimens clearly. From the nonlinear finite element analysis results for the tensile test specimens, tensile strengths of test specimens with irregular sectional damaged surface were relatively evaluated to be highly decreased than these of FE analysis model with equivalent sectional damage. Therefore, residual tensile strengths of tensile members with irregular sectional damage as local corrosion can be evaluated and predicted using correlation coefficient between tensile test results and FE analysis results with equivalent sectional damage.

• Computational Structural Engineering
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• v.3 no.3
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• pp.20-24
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• 1990

현재까지의 철근콘크리트(R/C)부재의 이력거동을 예측하기 위한 이론적 연구는 대부분이 휨 변위량이 전체 변위량을 지배한다는 가정하에 휨 해석을 행하고 있다. 그러나 지진과 같은 탄성한계를 벗어난 강한 동적반복하중을 받는 경우 철근 콘크리트 부재의 변위량은 휨 변위량 뿐만 아니라 전단 변위량 및 부재연결부에서의 회전 변위량에 의해 지배됨이 많은 연구를 통해 밝혀졌다. 전단이력거동은 강성과 강도저하가 심하게 나타나고 낮은 에너지 발산능력을 갖는 특징에 의해 휨 이력거동과는 구별되며 반복하중이 계속되면 강성이 저하되는 경향때문에 전단변형이 R/C부재의 거동을 지배하게 된다. 이러한 부재거동의 특징에 견주어 볼 때 현재 사용되고 있는 해석모델을 이용하여 동적응답을 예측하고, 해석하여 설계된 기존의 R/C부재는 강한 동적하중을 받을 경우 해석적으로는 전혀 예측치 못하게 되는 결과를 초래하게 된다.

• Journal of the korean Society of Automotive Engineers
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• v.15 no.5
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• pp.15-21
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• 1993

본 연구에서는 자동차 차체의 경량화 방안으로서 섬유강화 복합재료를 이용한 충격흡ㅅ수 구조재인 Side Member(측면부재)의 응용을 위한 시뮬레이션용 Box Tube의 충돌에너지 흡수특성 및 거동에 대해서 기존 금속 측면부재와 비교하여 논의해 보고자 한다. 1. 금속 충돌흡수 부재의 붕괴거동. 2. 복합재료 충격흡수부재의 붕괴거동.

• Computational Structural Engineering
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• v.8 no.1
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• pp.115-122
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• 1995

For the three dimensional analysis of linearly tapered members, the stiffness matrices are derived. Significant improvements of accuracy and efficiency of the analysis are achieved by using the stiffness matrices developed in this study. Results of these analysis are compared with those based upon stepped representation of beam elements in the ANSYS. The stiffness matrices presented in this study can be used for the analysis of tapered and prismatic members.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.231-234
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• 2011

본 논문은 교량의 안전진단을 위한 각 부재의 명명체계에 따라 직선형 교량모델의 각 부재에 대한 솔리드 객체의 고유번호를 일괄적으로 부여하기 위한 방법론을 제시한다. 개발된 방법론은 크게 3 단계의 프로세스로 이루어진다. 먼저, 부재의 종류별로 구분된 레이어로부터 각 부재에 대한 솔리드 객체의 도심을 추출하고, 이를 시점과 종점으로 이루어진 교축방향을 축으로 한 국부좌표계에 대해 변환한다. 이후 교축방향으로 정렬되는 객체를 식별하여 그룹핑하고 이를 교축 및 교축의 직각방향으로 순서로 정렬한다. 마지막으로 각 그룹 내 세그먼트들을 교축방향으로 정렬한다. 개발된 방법론에 따른 시범 응용모듈을 개발하였으며, 트러스 구조와 서로 다른 모델 좌표계를 가진 시범 교량모델을 대상으로 추출된 그룹의 개수와 각 객체의 명칭을 원래의 모델과 비교하여 그 적용성을 검토하였다.