In conventional construction practices, roof-parapet junction structures inevitably disrupt the insulation installation's continuity, leading to energy loss and thermal bridging. To address this issue, parapet thermal breaks were installed to interrupt the heat flow between the roof and the parapet, effectively preventing thermal bridging and energy loss and thereby reducing overall energy loss in buildings. This study equipped three experimental specimens with the developed parapet thermal breaks to verify their structural performance. These specimens were subjected to unidirectional loading under displacement-controlled conditions. The structural performance of these insulation structures was evaluated by comparing and analyzing the test results with corresponding analytical studies conducted using a finite element analysis program. In addition, five analytical models with varying parameters of the parapet thermal breaks were developed and compared against the baseline model. Consequently, the most efficient shape of the parapet thermal break was determined.

This study was conducted to investigate the proper design of alpha board used to support concrete blocks under high loads. A board height of 50 mm was appropriate to ensure a deflection of 3 mm or less under a load of 5 tons. The trapezoidal shape of the vibration absorbers in the interior of the board reduced the maximum deflection by evenly distributing the deflection across the board width. The height of the board is the most important variable in preventing deflection, and for the same board height, adjusting the thickness of the top and bottom plates was more effective in reducing the amount of deflection than adjusting the thickness of the stiffener. The theoretical solution is a good tool for easily predicting the deflection of the board, as it shows a difference of 5 to 15% from the simulation results. However, as a 2D prediction model, the theoretical solution cannot represent the distribution of deflection over the entire board area, so the 3D simulations are necessary in predicting the amount of deflection over the entire board.

The recent surge in energy consumption has sharply increased the use of fossil fuels, leading to a steep rise in the concentration of greenhouse gases in the atmosphere. Interest in hydrogen is growing to mitigate the issue of global warming. Currently, hydrogen energy is transported in the form of high-pressure gaseous hydrogen, which has the disadvantages of low safety and energy efficiency. To develop commercial hydrogen vehicles, liquid hydrogen should be utilized. Liquid hydrogen storage tanks have supports between the inner and outer cylinders to bear the weight of the cylinders and the liquid hydrogen. However, research on the design to improve the structural safety of these supports is still insufficient. In this study, through a thermal-structural coupled analysis of liquid hydrogen storage tanks, the model with three supports, which had the lowest maximum effective stress in the outer tank, inner tank, and supports as proposed in the author's previous research, was used to create analysis models based on the diameter of the supports. A structurally safe design for the supports was proposed.

본 논문에서는 초기 압축 성형 공정 조건들이 단섬유 강화 복합소재 구조물의 기계적 거동 특성에 미치는 영향을 효과적으로 반영 할 수 있는 압축 성형-구조 연계 해석 방안을 제안하였다. 압축 성형 해석을 바탕으로 초기 charge의 형상 및 배치에 따른 부위별 단섬 유 배향 특성을 분석하였으며, 평균장 균질화 이론을 통해 단섬유 배향 특성에 따른 등가 이방 물성을 도출하였다. 나아가, 단섬유 배 향 정보가 Mapping된 유한요소 모델을 기반으로 초기 공정 조건들에 의해 야기되는 부위별 거동 특성 변화를 고려할 수 있는 압축 성 형-구조 연계 해석을 진행하였다. 관련 수치 예제 검증을 통해 제시된 해석 방안은 압축 성형을 통해 제작된 단섬유 강화 복합소재 구 조물 설계 과정에서 효과적인 솔루션을 제공함을 확인하였다.

본 논문에서는 3D 프린팅 공정을 통해 제작된 단섬유 강화 복합소재 구조물의 기계적 거동을 효과적으로 예측하기 위한 AM 공정 연계 구조 해석 기법을 제안하였다. 복합소재 3D 프린터(Mark Two, Markforged)를 활용하여 다양한 노즐 경로를 갖는 인장 시편을 출력하였으며, 출력물에 대한 인장 시험을 진행하였다. 또한, 노즐 경로에 따른 부위별 이방 물성을 도출하기 위해 실험적 데이터를 기반으로 역공학 기법을 적용하였다. 제안된 AM 공정 연계 구조 해석 방안의 타당성을 검증하기 위해 실험 결과와의 비교/분석을 병 행하였으며, 부위별 이방 물성이 반영된 FE 모델을 바탕으로 AM 공정 연계 구조 해석을 수행함으로써 복합소재 3D 프린팅 출력물의 거동 양상을 정확하게 예측할 수 있음을 확인하였다.

The government declared ‘2050 carbon neutrality’ as a national vision in October 2020 and subsequently pursued the establishment of a ‘2050 carbon neutrality scenario’ as a follow-up response. Hydrogen is considered as one of the most promising future energy carriers due to its noteworthy advantages of renewable, environmentally friendly and high calorific value. Liquid hydrogen is thus more advantageous for large-scale storage and transportation. However, due to the large difference between the liquid hydrogen temperature and the environment temperature, an inevitable heat leak into the storage tanks of liquid hydrogen occurs, causing boil-off losses and vent of hydrogen gas. Researches on insulation materials for liquid hydrogen are actively being conducted, but research on support design for minimal heat transfer and enhanced rigidity remains insufficient. In this study, to design support structures for liquid hydrogen storage tanks, a thermal-structural coupled analysis technique was developed using Ansys Workbench. Analytical models were created based on the number and arrangement of supports to propose structurally safe support designs.

이 논문에서는 교량받침 교체용 통공앵커의 충전조건과 하중조건에 따른 구조적 안전성을 유한요소해석을 통해 확인하였다. 에폭시의 충전여부와 하중조건을 변수로 두어 통공앵커의 구조적 거동을 확인한 결과 에폭시 완충 시 앵커에 정적수평하중이 균등하게 작용하여 통공앵커가 작용하중에 저항하여 구조물의 국부적인 파괴를 방지 가능하였다.

In this study, the design of fuel tank for SUVs (sports utility vehicles) was addressed through structural FE-simulation. For safety evaluation, we performed a shape analysis of fuel tank, discovered improvement measures for weak areas, and reflected them in the fuel tank design. Additionally, a strength analysis was conducted and the analysis results were reflected in the design. As a result of analysis through various design changes, it was possible to propose an appropriate fuel tank shape. Additionally, the effect of changes in the shape of the reinforcement and mounting bracket on the stiffness and strength of the fuel tank bracket was investigated.

V-type coupling, which is often applied to wastegate-turbochargers(WGT), is a mechanical fastener. Its radial forces generated from the bolt pretension load colse contact with each other to the axial direction for turbine housing and center housing rotating assembly(CHRA). In addition, the torsional stiffness between two bodies should be sufficiently secured to minimize the linkage angle change from the EWGA to the valve spindle. Therefore, in this study, the torsional stiffnesses according to the effects of positioning pins and friction coefficient, and the bolt pretension loads were calculated for V-coupling turbocharger. As a result, it can be seen that the torsional stiffness of the coupling according to the number of position pins is very small. And, when the friction coefficient and the axial force of the bolt are large, the torsional stiffness is greatly increased, and gradually decreasing when the bolt load of the coupling is about 6,000 N or more.

Hydrogen is considered as one of the most promising future energy carriers due to its noteworthy advantages of renewable, environmentally friendly and high calorific value. However, the low density of hydrogen makes its storage an urgent technical problem for hydrogen energy development. Compared with the density of gas hydrogen, the density of liquid hydrogen is more than 1.5 times higher. Liquid hydrogen is thus more advantageous for large-scale storage and transportation. However, due to the large difference between the liquid hydrogen temperature and the environment temperature, an inevitable heat leak into the storage tanks of liquid hydrogen occurs, causing boil-off losses and vent of hydrogen gas. Researches on insulation materials for liquid hydrogen are actively being conducted, but research on support design for minimal heat transfer and enhanced rigidity remains insufficient. In this study, to design support for liquid hydrogen storage tank, technique of thermal-structural coupled analysis including geometry, mesh, and boundary condition were developed using Ansys workbench, and equivalent stress and deformation distributions were analyzed.

In this study, the design of parking brake mounting bracket for SUVs (sports utility vehicles) was handled through structural analysis. For safety evaluation, we conducted a shape analysis of parking brake mounting bracket, discovered improvement measures for weak areas, and reflected them in the design. In addition, a strength analysis was performed and the analysis results were reflected in the design. As a result of analysis through various design changes, it was possible to suggest an appropriate parking brake mounting bracket shape. In addition, the effect of changes in the shape of the reinforcement and mounting bracket on the stiffness and strength of the parking brake mounting bracket was investigated.

In the development of eco-friendly vehicles such as electric vehicles, weight reduction has become a very important design target. Seat weight reduction is very important in vehicle weight reduction. In this study, the energy absorption characteristics of Almag material, an alloy of aluminum and magnesium, and mild steel SAFH440, SAFH590, SAFC780, and SAFH980 were analyzed to obtain a true stress versus true strain curve that was correlated with the test. By performing the seat frame structure analysis using the obtained analysis material property, it was possible to compare the deformation between lightweight material, Almag and mild steel materials. In addition, it was confirmed that the weight reduction effect was 25.8% when applying Almag, an equivalent lightweight material that gives the same maximum deformation as SAFH980, a high-strength mild steel.

본 논문에서는 조선 후기의 대표적인 전통목구조인 수원 화령전 운한각의 구조성능을 평가하였다. 운한각의 가구구성 방식에 맞추 어 3차원 구조해석 소프트웨어인 midas Gen으로 해석모델을 정교하게 구축하였다. 정적해석으로 주요 구조부재의 안전성과 사용성 을 평가하였고, 고유치해석으로 동적거동특성을 평가하였다. 대부분의 부재가 안전성 및 사용성 기준을 여유 있게 만족하고 있으나, 외목도리에서 휨응력비가 기준을 20.7% 초과하고 있어 이 부재에 대해서는 장기적인 모니터링이 필요하다고 사료된다. 운한각의 고 유주기는 1.079초로 비슷한 규모의 전통목구조보다 약간 긴 편이며, 특히 후면 화방벽의 영향으로 2차모드에서 비틀림이 발생한 것으 로 분석된다.

In this study, the shape evaluation and design of the spare tire carrier for SUV (sports utility vehicle) were addressed through structural analysis. Spare Tire Carrier analysis was conducted to evaluate rigidity, and strength and improvement measures for appropriate shapes were found and reflected in the design. Through structural analysis of the spare tire carrier, this study was conducted to derive an optimal design plan as the stiffness and strength needed to be increased for stable installation of the spare tire carrier. Compared to the existing model, the bar, which was curved, was changed to a straight line to shorten the length, thereby increasing rigidity. In addition, because the moment was concentrated in the structure of the rear hanger mounting bracket, the side part of the bracket was extended, but the cross member stiffness was relatively weak, so it did not have a significant effect.

In this study, the shape evaluation and design of clamp mount for SUVs (sports utility vehicles) was dealt with through structural analysis. The clamp mount analysis was performed to evaluate stiffness, strength and improvement plans for appropriate shape were found and reflected in the design. In addition, strength analysis and was performed in parallel to solve the problem of rib design around the edge part of the clamp mount and the thickness effect results were reflected in the design. As a result of analysis through various design changes, it was possible to present an appropriate reinforcement design shape. In addition, when the thickness of the fuel tank was changed from 3.2mm to 4.0mm, the stiffness of the fuel tank decreased by approximately 30%, and reinforcement was required.

유체-구조물-지반 상호작용을 고려한 액체저장탱크의 유한요소 모형을 제시하고, 비선형 지진응답 해석기법을 정식화한다. 탱크 구조물은 기하 및 재료 비선형 거동을 고려할 수 있는 쉘 요소로 모델링한다. 유체의 거동은 acoustic 요소로 구현하고, interface 요소 를 사용하여 구조물과 결합한다. 지반-구조물 상호작용을 고려하기 위해 지반의 근역과 원역을 각각 solid 요소와 perfectly matched discrete layer로 모델링한다. 예제 20만 kl급 액체저장탱크의 지진취약도 해석에 적용하여, 유연한 지반에 구조물이 놓인 경우 부지에 서의 암반노두운동의 증폭 및 필터링으로 인해 지진취약도의 중앙값과 대수 표준편차가 감소하는 것을 관찰할 수 있다.