• 한국철도학회:학술대회논문집
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• 한국철도학회 2001년도 춘계학술대회 논문집
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• pp.193-199
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• 2001

In this study, the carbody design of the rubber tired AGT(Automated Guide-way Transit System) under development by KRRI was numerically analysed to evaluate its structural strength according to the standard specifications for Korean LRT (Light Rail Transit). The numerical results showed that the detail design of the carbody was strong enough to satisfy the specifications with respect to the axial compression strength, the vertical strength and the vertical stiffness(natural frequency). However, the carbody design had some problems on the fatigue strength by twist loadings. So, it was recommended that the carbody design should be modified to improve the twisting strength by reinforcing the front end structures.

• 한국기계가공학회지
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• 제15권3호
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• pp.58-65
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• 2016

This study analyzed the structural weld strength for a door hinge for a field artillery ammunition support vehicle. In order to determine the optimal conditions, we measured the modal analysis and analyzed the leg length of a rear door hinge. From these methods, we acquired the vibration frequency of normal mode and the optimal welding leg length conditions. It was possible to obtain a structural stability for a rear door hinge of the field artillery ammunition support vehicle. In the future, this should be used as a reference source for the weld strength analysis of high vibration and high weight structures for another welding system design.

• Computers and Concrete
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• 제20권5호
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• pp.511-519
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• 2017

The reliability of reinforced concrete structures is frequently compromised by the deterioration caused by reinforcement corrosion. Evaluating the effect caused by reinforcement corrosion on structural behaviour of corrosion damaged concrete structures is essential for effective and reliable infrastructure management. In lifecycle management of corrosion affected reinforced concrete structures, it is difficult to correctly assess the lifecycle performance due to the uncertainties associated with structural resistance deterioration. This paper presents a stochastic deterioration modelling approach to evaluate the performance deterioration of corroded concrete structures during their service life. The flexural strength deterioration is analytically predicted on the basis of bond strength evolution caused by reinforcement corrosion, which is examined by the experimental and field data available. An assessment criterion is defined to evaluate the flexural strength deterioration for the time-dependent reliability analysis. The results from the worked examples show that the proposed approach is capable of evaluating the structural reliability of corrosion damaged concrete structures.

• 대한조선학회 특별논문집
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• 대한조선학회 2015년도 특별논문집
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• pp.1-8
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• 2015

In general, the strength assessment for heavy lift vessel is carried out under two stages. The first stage is to comply with the requirement of KR (Korean Register of Shipping) Steel Barges and Rules for Classification of Steel Ships. At the second stage, the structural strength analysis by Finite Element Method is peformed. This paper describes the strength assessment considering various loads for the heavy lift vessel of sheerleg type.

• Steel and Composite Structures
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• 제39권5호
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• pp.583-598
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• 2021

The composite steel reinforced concrete (SRC) columns have been widely used in Structural Engineering due to their good performances. Many studies have been done on the SRC columns' performances, but they focused on the ordinary types with conventional configurations and materials. In this study, nine new types of steel reinforced lightweight aggregate concrete (SRLAC) short columns with cross-shaped (+shaped and X-shaped) steel section were tested under monotonically axial compressive load; the studied parameters included steel section ratio, steel section configuration, ties spacing, lightweight aggregate concrete (LWAC) strength, and longitudinal bars ratio. From the results, it could be found that the specimens with larger ties ratio, concrete strength, longitudinal bars ratio, and steel section ratio achieved great strength and stiffness due to the excellent interaction between the concrete and steel. The well-confined concrete core could strengthen the steel section. The ductility and toughness of the specimens were influenced by the LWAC strength, steel section ratio, and longitudinal bars ratio; in addition, larger ties ratio with smaller LWAC strength led to better ductility and toughness. The load transfer between concrete and steel section largely depends on the LWAC strength, and the ultimate strength of the new types of SRLAC short columns could be approximately predicted, referring to the codes' formulas of ordinary types of steel reinforced concrete (SRC) columns. Among the used codes, the BS-5400-05 led to the most conservative results.

• 한국가구학회지
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• 제10권2호
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• pp.1-8
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• 1999

The use of structural wood based panels like plywood, OSB in many applications involves the use of nails, and data on the performance of panel-nail connection are needed for design and comparative purpose. This study was carried out to develop basic information on nail performance(withdrawal, embedding, nailhead push through) with water absorption in plywood and OSB. In withdrawal resistance test, initial stiffness of plywood performed better than OSB in 24hr soaked condition. The soaked condition reduced average nail withdrawal resistance value about 46% (12d mail), 53%(8d nail) in OSB, 17%(12d mail), 24%(8d mail) in plywood. The nail embedding strength of plywood also performed better than that of OSB and retention value(wet strength/dry strength) yielded similar in each nail types. The nail head push through capacity of OSB was higher than that of plywood in dry condition, but equal or lower in soaked condition. Therefore, critical consideration about structural panels is required in moist applications. The average values of nail withdrawal, nail embedding strength and nail head push through resistance of tested materials meet the minimum requirement of various specification and standards.

• 한국항공우주학회지
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• 제38권4호
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• pp.376-381
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• 2010

일반적으로 기체 구조물 개발시 운용조건에서의 구조설계 해석 검증 및 구조강도확인을 위해서 구조강도시험이 수행된다. 본 논문에서는 구조시험 하중부가방법 중 응력집중에 의해 파손되기 쉬운 재료를 기체 지지구조로 사용하고자 할 때 구조물 표면에 공기압을 이용하여 국부적 응력집중을 피하면서 분포하중을 부가할 수 있는 새로운 외력부가장치의 개발에 대하여 기술하였다. 본 장치는 부드러운 재질의 하중전달용 매개체를 이용하여 구조물 표면에 손상을 주지 않고 외력을 전달할 수 있으며, 임의형상 구조물에 대하여 쉽게 응용이 가능하다. 본 장치를 이용하여 평판구조물과 곡면구조물에 대하여 외력부가구조강도시험을 성공적으로 수행함으로써 적용시험기법의 타당성을 입증하였다.

• Structural Engineering and Mechanics
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• 제58권6호
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• pp.989-999
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• 2016

Moist curing of concrete is a time consuming procedure. It takes minimum 28 days of curing to obtain the characteristic strength of concrete. However, under certain situations such as shortage of time, weather conditions, on the spot changes in project and speedy construction, waiting for entire curing period becomes unaffordable. This situation demands early strength of concrete which can be met using accelerated curing methods. It becomes necessary to obtain early strength of concrete rather than waiting for entire period of curing which proves to be uneconomical. In India, accelerated curing methods are used to arrive upon the actual strength by resorting to the equations suggested by Bureau of Indian Standards' (BIS). However, it has been observed that the results obtained using above equations are exaggerated. In the present experimental investigations, the results of the accelerated compressive strength of the concrete are used to develop the regression models for predicting the short term and long term compressive strength of concrete. The proposed regression models show better agreement with the actual compressive strength than the existing model suggested by BIS specification.

• 대한조선학회논문집
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• 제53권2호
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• pp.108-114
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• 2016

Recently, there has been a growing interest in marine leisure sports and high speed power boat for fishing. The prototype of 20 feet class power boat was developed and authors are joined in this government-led project. The research was performed to evaluate the optimal structure and design of the structural strength necessary to ensure the structural safety of the power boat. A new material ROCICORE fiber added to the mat and roving was adopted for high-power tenacity. ANSYS Workbench has been used to make the structural model, evaluate the strength and optimize the structural design. The response of the structure to quasi-static slamming loads according to the rules and regulations of ISO 12215-5, Lloyd’s Register of Shipping and Korean Register has been implemented and studied. An optimization study for the structural response is carried out by changing the plate thickness and section modulus of stiffeners. The power boat structure derived fuel efficiency is optimized by performing the best possible structural design to minimize the hull weight.

• 한국철도학회논문집
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• 제13권5호
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• pp.469-475
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• 2010

본 논문은 국내에서 개발중인 모노레일 대차 프레임에 대해 구조 안전성 및 피로강도를 평가하였다. 현재 모노레일 대차 프레임에 대한 평가기준은 없는 실정이며, 이에 구조 안전성 및 피로강도 평가는 유럽규격인 UIC 615-4 기준을 적용하여 수행하였다. 이때, 설계된 대차 프레임에 대해 각 하중조건에서의 변위 및 Von-Mises 응력 결과를 통해 구조 안전성을 평가하였다. 그리고 피로강도는 UIC 615-4 기준의 규정에 따라 조합 주 운용하중조건에 의해 평가되고, 일괄처리 기능을 갖는 winLIFE v3.1을 이용한 피로해석 결과와 비교 검증하였다. 본 연구를 통하여 설계된 대차 프레임은 구조적 안전성 및 피로강도를 만족하였으며, 일괄처리 기능을 갖는 피로해석은 조합하중을 이용한 기존 피로해석보다 더 효율적임을 확인하였다.