• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.358-363
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• 2008

Through this study, 2D multibody dynamics models for analysis of train collisions have been developed to evaluate the crashworthiness requirements of the TSI regulation. The crashworthiness regulation requires some performance requirements for two heavy collision accident scenarios; a train-to-train collision at the relative speed of 36 kph, and a collision against a standard deformable obstacle of 15 ton at 110 kph. The complete train set will be composed of hybrid model with 2D and 1D model. Using numerical analysis of the hybrid model, some crashworthy design were evaluated in terms of mean crush forces and energy absorptions for main crushable structures and devices. especially, 2D model can evaluate overriding effect in train collisions. It is shown from the simulation results that the suggested hybrid model can easily evaluate the crashworthiness requirements.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.43-47
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• 2007

Based on experimental impact testing data, due to changing of velocity and mass of the impactor simultaneously under constant impact energy, crashworthiness of polyurethane foam has been observed. Dynamic tests were carried out in an instrumented impact-testing machine. Also, modified Sherwood-Frost model was proposed to investigate the crashworthy behaviour of rigid polyurethane foam under the condition of constant impact energy.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2001년도 추계학술대회 논문집
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• pp.223-228
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• 2001

In this paper, crashworthiness of the KHST carbodies is evaluated by numerical simulation under the SNCF accident scenario (collision against a movable rigid mass of 15 ton at 110 kph) and the scenario of train-to-train collision at 30 kph. The numerical results of the several simulations, such as the accident collided against a deformable dump truck of 15 tons at 110 kph, the driver's dummy analysis using the integrated analysis method, and the accident of train-to-train collision for the first three units at 30 kph, show good performances in the viewpoint of energy absorption and survival space.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 창립기념 춘계학술대회 논문집
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• pp.369-376
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• 1998

For a good crashworthy design of train vehicles, it is essential to develop some design and analysis techniques for energy absorbing structures. This paper analyzes the front structure of TGV-K and suggests crashworthy design of Korea high speed tram(KHST) using the accident scenario of SNCF(collision with a stationary rigid mass in motion of 15 ton at 110km/h). Specifically this research is concentrated on developing a well-designed protective headstocks using mullticell structures wi th cutouts to improve crashworthiness of KHST

• 산업기술연구
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• 제18권
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• pp.225-232
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• 1998

Train crashes involve complex interaction between deformable bodies in multiple collisions. The purpose of this study is to suggest the effective analytical procedure using finite element model for the crashworthiness of motorized trailer of high speed train. Various types of crash events are investigated and the conditions for numerical simulation are defined. Finally korean high speed train which consists of aluminum members can be analyzed and designed by the numerical simulation.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 추계학술대회 논문집
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• pp.511-518
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• 1999

Though not very often, a train accident can cause large number of fatality. As a result, public concern about its safety is increasing nowadays. Tn this paper, the structural crashworthiness of Korean High Speed Train trailer was examined through FE analysis. Crash analyses on energy absorbing part and safety zone were carried out to determine each section force. Rollover analysis was performed to observe the amount of intrusion in the passenger's area in case of rollover accident.

• 한국철도학회논문집
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• 제11권3호
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• pp.300-310
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• 2008

본 논문에서는 국내철도차량안전기준의 충돌안전 요구사항을 만족하는 동력 분산형 고속전철의 충돌안전도 개념설계에 대하여 연구하였다. 국내안전기준에는 36km/h 열차 대 열차 충돌, 15ton 변형체 장애물과 110km/h 충돌 등 2가지 중충돌 사고에 대한 충돌안전성능을 요구한다. 한국형 분산형 차세대고속열차는 17ton 축중의 동력집중형 KTX와 달리 13ton 축중을 가지는 2TC-6M로 구성된다. 이론적 수치적 해석을 통하여 주요 압괴구조 및 부품의 평균압괴하중과 변형량을 에너지 흡수 관점에서 충돌안전도 개념설계안으로 도출하였다. 도출된 개념 설계안은 1차원 막대-스프링-댐퍼-질량 동역학 시뮬레이션 결과로부터 국내 충돌안전기준을 잘 만족시킬 수 있음을 보였다.

• 한국자동차공학회논문집
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• 제10권1호
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• pp.153-161
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• 2002

This paper develops a finite element model for crashworthiness analysis ova small-sized bus. The full vehicle finite element model is composed of 31,982 shell elements,599 beam elements,42 bar elements, and 34,204 nodes. The model uses four material models (such as elastic, elastic-plastic(steel), rigid. and elastic-plastic (rubber) material model) of PAM-CRASH. The model uses four contact types to define sliding interfaces in ten areas. A frontal crash test using an actual vehicle with 30mph velocity to a rigid barrier is carried out. Vehicle pulses at lower part of left and right b-pillar are measured, and deformed shapes of frame and driver seat's lower left area are photographed. A frontal crash simulation using the developed full vehicle finite element model is performed with PAM-CRASH installed in super computer SP2. The simulation is performed with the same conditions as the test. The measured vehicle pulses and photographed deformed shapes from the test are compared to ones from the simulation to validate the reliability of the developed model.

• 한국자동차공학회논문집
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• 제10권1호
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• pp.216-233
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• 2002

Due to the environmental problems of fuel consumption and vehicle emission, etc., automotive makers are trying to reduce the weight of vehicles. The most effective way to reduce a vehicle weight is to use lighter materials, such as aluminum and plastics. Aluminum Intensive Vehicle(AIV) has many advantages in the aspects of weight reduction, body stiffness and model change. So, most of automotive manufacturers are attempting to develop AIV using Aluminum Space Frame(ASF). The weight of AIV can be generally reduced to about 30% than that of conventional steel vehicle without the loss of impact energy absorbing capability. And the body stiffness of AIV is higher than that of conventional steel monocoque body. In this study, Aluminum Intensive Vehicle is developed and analyzed on the basis of steel monocoque body. The energy absorbing characteristics of aluminum extrusion components are investigated from the test and simulation results. The crush and crash characteristics of AIV based on the FMVSS 208 regulations are evaluated in comparison with steel monocoque. Using these results, the design concepts of the effective energy absorbing members and the design guide line to improve crashworthiness for AIV are suggested.

• International Journal of Automotive Technology
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• 제1권1호
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• pp.35-41
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• 2000

The crashworthiness of vehicles with finite element methods depends on the geometry modeling and the material properties. The vehicle body structures are generally composed of various members such as frames, stamped panels and deep-drawn parts from sheet metals. In order to ensure the impact characteristics of auto-body structures, the dynamic behavior of sheet metals must be examined to provide the appropriate constitutive relation. In this paper, high strain-rate tensile tests have been carried out with a tension type split Hopkinson bar apparatus specially designed for sheet metals. Experimental results from both static and dynamic tests with the tension split Hopkinson bar apparatus are interpolated to construct the Johnson-Cook and a modified Johnson-Cook equation as the constitutive relation, that should be applied to simulation of the dynamic behavior of auto-body structures. Simulation of auto-body structures has been carried out with an elasto-plastic finite element method with explicit time integration. The stress integration scheme with the plastic predictor-elastic corrector method is adopted in order to accurately keep track of the stress-strain relation for the rate-dependent model accurately. The crashworthiness of the structure with quasi-static constitutive relation is compared to the one with the rate-dependent constitutive model. Numerical simulation has been carried out for frontal frames and a hood of an automobile. Deformed shapes and the Impact energy absorption of the structure are investigated with the variation of the strain rate.