• Journal of the Earthquake Engineering Society of Korea
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• v.15 no.2
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• pp.11-22
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• 2011

The design comparison and nonlinear analysis of totally prefabricated bridge substructure systems are performed. The prefabricated bridge substructures are designed by the methods of present design and load and resistance factor design (LRFD). For the design, the current Korea Highway Bridge Code (KHBD), with DB-24 and DL-24 live loads, is used. This study evaluates the present design method of KHBD (2005) and AASHTO-LRFD (2007) for totally prefabricated bridge substructure systems. A computer program, named RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), for the analysis of reinforced concrete structures, was used.

• Journal of Navigation and Port Research
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• v.38 no.3
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• pp.253-259
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• 2014

Traffic risks in fairway and harbour area increase lately according to be a sharpe change of ship's size and speed. It becomes hot issue to design a fairway, which's width is important to lower traffic risk and ensure navigational safety. The current design making a fairway and width do not focus on maneuvering motion of a large ship, but traffic risks are clear on reflecting the design of fairway, specially on width. To contact with these problems, this research proposes how to determine fairway' width in consideration of traffic volume. it suggests several situations of marine traffic congestion as like narrow channel and harbour area. here uses 162 simulations in MTS Ver.1 developed. Acquired simulation's results, environmental stress dates, figure in a model that relates with required fairway' width and allowable traffic volume. In added, suggested model compares current design with an width.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.32 no.2
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• pp.9-11
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• 2003

• Journal of Korean Society of Steel Construction
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• v.15 no.1
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• pp.51-57
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• 2003

Current steel-framed building design codes are based on theoretical and experimental researches on the conventional structural steel. However, the yield phenomenon of austenitic stainless steel, which is characterized by continuous yielding, is quite different from that of conventional structural steel. The offset strength, which should determine the design strength, may affect the limits of width-thickness ratio of current design codes. Stub column test results showed that the limits of width-thickness ratio satisfied both ASD and LRFD codes when 0.2% offset strength was regarded as design strength. In addition, the local buckling strengths of all stainless steel stub columns did not decrease rapidly compared with those of conventional structural steel columns, even though the width-thickness ratio exceeded the design limit.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.4
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• pp.133-140
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• 2008

The design method of the reinforced concrete structures is converting from the current limit state design method to the reliability based design method and active studies have been done in the US, Europe, and Japan etc. Performance based design method is considering lots of uncertainty of current design provision rationally and make sure that structure have a reliable reliability and safety. The main area of these studies is to secure the non-linear analysis technology with high reliability. The data for reinforced concrete columns tested by many researchers are used to verify the applicability of the nonlinear finite element analysis program (RCAHEST, Reinforced Concrete Analysis in Higher Evaluation System Technology). A comparison is made between analysis and test, calculated safety factor based on reliability theories to applies to analysis result.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.35-35
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• 2011

CFT가 갖는 다양한 구조적 이점으로 인해, 축력이 지배적인 기둥 구조물에만 주로 적용되던 CFT 요소가 점차 거더에 적용되어 가고 있다. 그러나, 현재 CFT 요소에 대한 설계 기준은 축력이 지배적인 보-기둥 구조물에 대한 것으로 제한되어 있으며, 휨이 지배적인 보 구조물에 대한 현행 설계 기준의 적용성을 검토해야 할 필요가 있다. 현행 설계기준에서 제시하고 있는 CFT 요소의 극한 강도 평가방법은 소성응력분배법 및 변형률적합법으로 구분되어지며, 각 방법을 이용한 극한 강도의 평가결과를 기존 연구자들의 CFT 요소 휨 실험결과와 비교 분석하였다. 휨 강성 평가에 대한 타당성을 검증하기 위해 AISC에서 제시하는 휨 강성 평가식을 기존 실험 연구와 비교 검토하였으며, 아울러 압축력에 따라 휨 강성을 보정할 수 있도록 수정된 Roeder et al.의 제안식을 함께 검토하였다. 검토 결과, 강도 평가에 있어서는 설계 기준에서 제안하는 두 방법 모두 CFT 거더의 휨 강도를 적절히 평가할 수 있었으며, 강성 평가에 있어서는 설계 기준의 제안식이 휨 초기 강성을 적절히 평가하는 반면 사용 단계에서의 휨 강성은 Roeder et al.의 수정된 강성 평가식에 의해 적절히 평가할 수 있음을 확인하였다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.5
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• pp.27-36
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• 2020

The purpose of this paper is to study on the applicability of the standard design response spectrum from the response spectrum analysis method, mainly applied to pile mooring facilities. To this end, after performing the ProShake 1-dimensional site response considering various geological conditions, the current standard design response spectrum was compared, and the ground-pile model in time history and two-dimensional site response analysis using Abaqus were performed to analyze the dynamic behavior of the ground-pile and to examine the selection method of the reference surface of the response spectrum on the installed slope, respectively. As a result, it was confirmed that no problems were found in the applicability of the current standard design response spectrum and no improvements are needed as well when considering the characteristics of the ground-pile dynamic behavior and the slope of the pile mooring facility.

• Journal of the Korean GEO-environmental Society
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• v.8 no.5
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• pp.57-65
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• 2007

Slope collapse occurs mostly at the rainy season or thawing season in Korea. From a engineer point of view, the design criterion in recent of soil slopes during the rainfall have a conservative tendency because a slope stability is evaluated in the condition that ground water level is located in the surface. However, for the rational design of soil slopes during rainfall, the raining conditions and the unsaturated soil characteristics of soil slopes have to be considered. For the unsaturated soil characteristics of soil slopes, the laboratory tests for unsaturated soils and the seepage analyses for the raining conditions have to be performed. Due to these difficulties, a conservative design of soil slopes in the current design criterion has been carried out. In this paper, therefore, a simple design method is proposed. The method is considered to the unsaturated soil characteristics and the results of seepage analysis without numerical analysis. To verify the suggested design method, it is compared with both analysis results by current design criterion and analysis results based on the seepage analysis. Through the comparative study, it was found that the current design criterion has been excessively conservative. Hence, simple design method in this study was evaluated as the rational design for the soil slopes during rainfall.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.6C
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• pp.251-258
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• 2009

In this study, the optimum design conditions for embankment construction on soft clay layer improved by soil compaction pile (SCP) are discussed by comparing the practical design method to the reliability design which is based on the loss function and advanced first order second moment (AFOSM) method. The results are summarized as follows; 1) the relationship between safety factor and failure probability becomes heavy exponentially, failure probability decreases rapidly till 1% approximately until safety factor is smaller than 1.2 and after then, failure probability decrease gradually along the increase of the safety factor. The design safety factor of 1.2 may be the critical value that has been established on considering both relationships appropriately, 2) the safety factor of 1.15 at the minimum expected total cost is a little smaller than the design safety factor of 1.2 and the failure probability is about 1%, 3) the sensitivities of the ratio of stress share and the internal friction angle of sand is larger than the variables related the undrained shear strength of soft layer. This result means that the distribution characteristic of n and ${\phi}$ influences on the stability analysis considerably and they should be considered necessarily on stability analysis of embankment on soft layer improved by SCP, 4) new failure points of the input variables at the design safety factor of 1.2(below failure probability of 0.1~0.3%) is far 1~2 times of standard deviation from the initial design values of themselves.

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.5
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• pp.1-9
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• 2003

The seismic design of the domestic concrete dams has done by seismic coefficient method considering inertia force, but this method has defect not reflect dynamic properties, as a conservative design method. Therefore, it is necessary for seismic design of dam to consider dynamic properties. Also, concrete dam evaluation of seismic performance has done by seismic coefficient method - in fact, it may done by dynamic analysis - that has many problems when applied to the domestic criteria. This study make a comparative analysis for result from seismic design and evaluation of seismic performance by seismic coefficient method, modified seismic coefficient method, and dynamic analysis method.