• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1631-1635
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• 2011

To consider dynamic magnification effect at the static design stage, impact load factor is applied to design load. Current impact load factor adopted EUROCODE without verification while Japan suggested impact load factor including velocity of high-speed train throughout theoretical and experimental studies. On the purpose of evaluate current impact load factor, this study investigated the calculation of impact load factor from dynamic response of running train.

• 대한기계학회논문집
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• 제14권2호
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• pp.298-309
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• 1990

In this paper, a new method is suggested to analyze impulsive stresses at loading poing of concentrated impact load under certain impact conditions determined by impact velocity, stiffness of plate and mass of impact body, etc. The impulsive stresses are analyzed by using the three dimensional dynamic theory of elasticity so as to analytically clarify the generation phenomenon of cone crack at the impact fracture of fragile materials (to be discussed if the second paper). The Lagrange's plate theory and Hertz's law of contact theory are used for the analysis of impact load, and the approximate equation of impact load is suggested to analyze the impulsive stresses at the impact point to decide the ranage of impact load factor. When impact load factors are over and under 0.263, approximate equations are suggested to be F(t)=Aexp(-Bt)sinCt and F(t)=Aexp(-bt) {1-exp(Ct)} respectively. Also, the inverse Laplace transformation is done by using the F.F.T.(fast fourier transform) algorithm. And in order to clarity the validity of stress analysis method, experiments on strain fluctuation at impact point are performed on a supported square glass plate. Finally, these analytical results are shown to be in close agreement with experimental results.

• 드라이브 ㆍ 컨트롤
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• 제16권2호
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• pp.1-7
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• 2019

Jaw crusher is a device that breaks rock collected from mines or quarries to produce aggregates of the size desired by user. A representative method for measuring load is to measure them by attaching force sensors directly to the part where the load is generated. However, the direct method has many limitations such as high-impact loads generation in equipment or space constraints, sensor capacities and costs. Therefore, Transfer Path Analysis (TPA) was used to indirectly measure impact loads by attaching acceleration sensors. In this study, both direct and TPA methods were used to measure the impact load of Jaw crusher. This study finally quantifies the impact of the load generated by the Jaw crusher using direct method and TPA method, and comparing the impact load measured calculated the derive the error rate.

• 한국해양공학회지
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• 제14권1호
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• pp.6-10
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• 2000

In this paper various methods of determining of wave loads acting ofshore structures including impact load due to breaking wave are studied and corresponding model test was performed. In the theoretical approach wave load by nonbreaking wave and impact load by breaking wave is determined by Morrison's equation Goda's equation and impact wave equation, In the experimental approach wave load by nonbreaking wave acting on cylindrical pile used in offshore structures is determined by measuring the strain on a cylindrical pile and compared with theoretical calue. in the numerical approach impact load by breaking wave acting on a modeled cylindrical pile is calculated by usign ANSYS FEM program and compared with theoretical value. It is found that the experimental and numerical results are comparable to theoretical results, Thus the determination of wave load acting on offshore structures can be obtained by a proposed methods and it acceptable.

• 오토저널
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• 제15권3호
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• pp.111-119
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• 1993

In this study, the transient impact structural stress analysis of tracked vehicle structures under recoil impact load is investigated. ANSYS, ABAQUS Code are used for modelling and analytical procedures. The highest maximum Tresca stress occurs on race ring portion and its stress level is (.sigma.$_{T}$)$_{max}$ =20-40kgf/m $m^{2}$. The second highest stress occurs on upper plate of chassis and down plate of turret. The maximum stress level increases with loading direction and elevation angle. The results from liner static load analysis are very much different with impact analysis. Therefore, the practical solutions of structures under impact load can be obtained by only nonlinear transient impact analysis. The impact stress analysis of the steel vehicle structures is conducted. The maximum stress level is less than (.sigma.$_T/)$_{max}$m $m^{2}$. So, the design concept of steel structures can be adapted for new alternatives.s.s.s..s.

• 한국철도학회논문집
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• 제6권4호
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• pp.239-245
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• 2003

In this paper, the track impact factor of conventional line was evaluated using the data for wheel load measured in field and the properties of current operating trains. The equation for track impact factor was presented through the statistical analysis of variational ratio in wheel load and compared with other design equations in domestic and foreign countries. A review on the safety of track system in conventional line was made from the relationship between the velocity and the corresponding impact factor. It was found that the impact factor from the proposed equation is a little less than the values from the equations adopted in both AREA and domestic railway, while it is same as the equation for continuous welded rail(CWR) in Japan. Therefore it could be said that the track satisfies a criteria for dynamic load caused by the train and the corresponding level of safety is guaranteed for dynamic load of the train

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.182-183
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• 2014

In case of large soft body impact test at the construction site, the test conditions are different from conditions at the laboratory, and the length of rope to hold the impact specimen must be changed. In a previous study, the fact that the size of impact load is varied by the length of rope on the large soft body impact specimen was confirmed. In this study, the length of rope and fall height were set as independent variables to conduct the load analysis test. It was determined that the load fluctuation was occurred depending on the length of rope under the fall height over 100 mm, and it is concluded that the additional setup of fall height to modify the actual impact load size is required when the length of rope is below 2.5 m. In this study, the modified formula to put equal size of impact load regardless of the length of rope was extracted through the experiment.

• Structural Engineering and Mechanics
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• 제32권3호
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• pp.371-382
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• 2009

Response of harbor structure to environmental loads such as wave load, impact load, ship's contacting load, is a fundamental factor in designing of the structure's optimal configuration. In this paper, typical environmental loads against coastal structures are investigated for designing of the optimal harbor structure. Loads to be considered here are wave load, impact load and contacting load due to ship mooring. Statistical analysis for several harbor structure types under the corresponding loads is carried out, followed by investigation of effect of individual environmental load. Based on these, the optimal configuration for the harbor structure is obtained after considerable engineering process. Estimation of contacting load of the ship is suggested using effective energy concepts for the load, and analysis of structural behavior is done for the optimal designing of the structure in the particular load. A guideline for the design process of the harbor structure is established, and safety of the structure is examined by proposed scheme. For verification of the analytical approach, various steel-piled coastal structures and caissons are chosen and relevant structural analyses are carried out using the Finite Element Methods combined with MIDAS/GTS and ANSYS code. It is found using the Morison equation that impact load cannot be a major load in the typical harbor structure compared with the original wave load, and that configuration shape of the structure may play an important role in consideration of the response criteria.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.1025-1028
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• 2005

Generally, fiber-reinforced composites have the highest possibilities of impact damages with external object collisions. Also, resulting in fatigue fracture considering the continued impact load. For the reasons mentioned above, the accurate understanding of interactions between the impact of composites and the fatigue load will be essential to understand the safety level of material structures. Furthermore, the composite materials and structures, due to the geometrical effect, vary the life in connection with the impact-fatigue. Therefore, I have reached the point that a focus of this study will be to evaluate fatigue fracture characteristics by the impacts-fatigue load of fiber-reinforced composites. Thus, in this paper, I have tried to work on impacts-fatigue load causing aspects and impact characteristics through impact-fatigue test on HTV-5Hl Black 9250 material made- structure, along with to evaluate the expected lift of real structures, the FEM analysis was carried out.

• 한국안전학회지
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• 제27권6호
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• pp.138-143
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• 2012

In this thesis, the relationship between the load carrying capacity and the transformed impact factor of the highway bridges were studied. The bridges are classified according to superstructures type. The result of the comparison between the load carrying capacity and the transformed impact factor, if the load capacity ratio of 0.57, the transformed impact factor was less in order of RC T-beam bridge, RC slab bridge, PC beam bridge, I-beam bridge. By the regression analysis on these results, the empirical formulae to predict the the load carrying capacity of bridge were suggested.