• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.659-662
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• 2004

An analysis of the AF is performed for each bridge pier exposed to ship collision. From this analysis, the impact lateral resistance can be determined for each pier. The bridge pier impact resistance is selected using a probability-based analysis procedure in which the predicted AF, from the ship collision risk assessment is compared to an acceptance criterion. In this study, the acceptance criterion is allocated to each pier using allocation weights based on the previous predictions. To determine the design impact lateral resistance of bridge components such pylon and pier, the numerical analysis is performed iteratively with the analysis variable of impact resistance ratio of pylon to pier. The design impact lateral resistance can vary greatly among the components of the same bridge, depending upon the waterway geometry, available water depth, bridge geometry, and vessel traffic characteristics.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4D
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• pp.539-546
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• 2011

Traffic accident collision interpretation is composed of various shapes, and speed variations working to the vehicle during collision are utilized as a very important factor in evaluating collision degrees between vehicles and safety of passengers who got in the vehicle. So, methods of interpreting results on speed variations utilizing simulation programs on the collision interpretation become necessary. By the way, reliability evaluation on each program is being required because various collision interpretations simulations are spread widely. This study utilized collision interpretation programs such as EDSMAC and PC-CRASH adopting completely different physical approaches, and then carried out collision experiments of one-dimensional front and two-dimensional right angle while changing values of a lot of collision factors such as vehicle's weight, center of gravity, rolling resistance, stiffness coefficient, and braking forces among early input conditions. Also, the study recognized effects of collision factors to speed variations as output results during crashing. As a result of this research, two simulation programs showed same speed variations together on the vehicle's weight, center of gravity, and braking forces. Stiffness coefficient of the vehicle reacted to EDSMAC only, and rolling resistance coefficient did not affect any particular influences on speed variations. However, there appeared a bit comparative differences from the speed variation's values, and this is interpreted as responding outcomes by applying fixed properties values to each simulation program plainly. Therefore, reliability on analysis of traffic accident collisions shall be improved by doing speed analysis after taking the fixed value of simulation programs into consideration.

• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.4
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• pp.169-176
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• 2005

An analysis of the annual frequency of collapse(AF) is performed for each bridge pier exposed to ship collision. From this analysis, the impact lateral resistance can be determined for each pier. The bridge pier impact resistance is selected using a probability-based analysis procedure in which the predicted annual frequency of bridge collapse, AF, from the ship collision risk assessment is compared to an acceptance criterion. The analysis procedure is an iterative process in which a trial impact resistance is selected for a bridge component and a computed AF is compared to the acceptance criterion, and revisions to the analysis variables are made as necessary to achieve compliance. The distribution of the AF acceptance criterion among the exposed piers is generally based on the designer's judgment. In this study, the acceptance criterion is allocated to each pier using allocation weights based on the previous predictions.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1A
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• pp.1-9
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• 2006

An analysis of the annual frequency of collapse(AF) is performed for each bridge pier exposed to ship collision. From this analysis, the impact lateral resistance can be determined for each pier. The bridge pier impact resistance is selected using a probability-based analysis procedure in which the predicted annual frequency of bridge collapse, AF, from the ship collision risk assessment is compared to an acceptance criterion. The analysis procedure is an iterative process in which a trial impact resistance is selected for a bridge component and a computed AF is compared to the acceptance criterion, and revisions to the analysis variables are made as necessary to achieve compliance. The distribution of the AF acceptance criterion among the exposed piers is generally based on the designer's judgment. In this study, the acceptance criterion is allocated to each pier using allocation weights based on the previous predictions. To determine the design impact lateral resistance of bridge components such pylon and pier, the numerical analysis is performed iteratively with the analysis variable of impact resistance ratio of pylon to pier. The design impact lateral resistance can vary greatly among the components of the same bridge, depending upon the waterway geometry, available water depth, bridge geometry, and vessel traffic characteristics. More researches on the allocation model of AF and the determination of impact resistance are required.

• Journal of Ship and Ocean Technology
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• v.6 no.3
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• pp.1-12
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• 2002

In this paper the results are reported of sixty-nine lateral collision tests, which were performed to investigate the collision resistance of plates. For the tests a collision testing machine of spring-roller conveyer type was designed and fabricated. Using this machine, various plates were tested with different masses and velocities and various headers of the striker. A simple analytical method has also been developed to predict the extent of damage of struck plates due to lateral collision. In the method, it is assumed that the kinetic energy of the striker can be dissipated by the formation of yield lines and membrane tensions in the impacted plate. The calculated predictions of extent of damage using the developed method have been substantiated with the test results, which shows reasonably acceptable correlations.

• Nuclear Engineering and Technology
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• v.45 no.4
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• pp.553-564
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• 2013

This study evaluates the local damage of a turbine in an auxiliary building of a nuclear power plant due to an external impact by using the LS-DYNA finite element program. The wall of the auxiliary building is SC structure and the material of the SC wall plate is high manganese steel, which has superior ductility and energy absorbance compared to the ordinary steel used for other SC wall plates. The effects of the material of the wall, collision speed, and angle on the magnitude of the local damage were evaluated by local collision analysis. The analysis revealed that the SC wall made of manganese steel had significantly less damage than the SC wall made of ordinary steel. In conclusion, an SC wall made of manganese steel can have higher effective resistance than an SC wall made of ordinary steel against the local collision of an airplane engine or against a turbine impact.

• Advances in concrete construction
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• v.7 no.1
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• pp.23-30
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• 2019

Five key items were used to create an economical and physically small impact test device for concrete panels subject to high speed collision: an air-compressive system, carbon steel pipe, solenoid valve, carrier and carrier-blocking, and velocity measurement device. The impact test device developed can launch a 20 mm steel spherical projectile at over 200 m/s with measured impact and/or residual velocity. Purpose for development was to conduct preliminary materials tests, prior to large-scale collision experiments. In this paper, the design process of the small impact test device was discussed in detail.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.5
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• pp.88-92
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• 2002

This research is about slurry wear of SM45C and SUS304, which using standard sand and KUM river sand. The results are as follows ; 1. Mass loss rates of both standard sand and KUM river sand were linearly increased as increasement of time and velocity. 2. The average diameter of sand from relatively, less wear rate and portion of larger particles. 3. Wear resistance was linear with time and velocity of liquid jet regardless of type of sand. Also, it was able to evaluate with the formula, $HV^2$/E calibrated with n, the velocity index. 4. The wear surface in liquid jet experiment was smooth. The maximum wear depth was observed at the location 2~4mm apart from the center in the condition of $90^{\circ}$ of collision angle 6mm of nozzle diameter, and 20mm of collision distance. The sectional shape in radial appeared as 'W'shape.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.798-801
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• 2001

This research is about slurry wear of SM45C and SUS304, which using standard sand and KUM river sand. The results are as follows ; 1. Mass loss rates of both standard sand and KUM river sand were linearly increased as increasement of time and velocity. 2. The average diameter of sand from relatively, less wear rate and portion of larger particles. 3. Wear resistance was linear with time and velocity of liquid jet regardless of type of sand. Also it was able to evaluate with the formula, HV2/E calibrated with n, the velocity index. 4. The wear surface in liquid jet experiment was smooth. The maximum wear depth was observed at the location, 2~4mm apart from the center in the condition of 90$^{\circ}$of collision angle 6mm of nozzle diameter, and 20mm of collision distance. The sectional shape in radial appeared as 'W' shape.

• Korean Journal of Materials Research
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• v.29 no.9
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• pp.525-531
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• 2019

The widespread use of automobiles has greatly increased energy demand and exhaust gas pollution. In order to save energy, reduce emissions and protect the environment, making lightweights automobiles is an effective measure. In this paper, carbon fiber composites and automobile B-pillars are briefly introduced, and then the mechanical properties and impact resistance of the DC590 steel B-pillars and carbon fiber composites B-pillars are simulated by the ABAQUS finite element software. The results show that the quality of compound B-pillars is reduced by 50.76 % under the same dimensions, and the mechanical property of unit mass is significantly better than that of metal B-pillars. In the course of a collision, the kinetic energy of the two B-pillars is converted into internal energy, but the total energy remains the same; the converted internal energy of the composite B-pillars is greater, the deformation is smaller and the maximum intrusion and intrusion speed is also smaller, indicating that the anti-collision performance of the composite B-pillars is excellent. In summary, the carbon fiber composites can not only reduce the quality of the B-pillars, but also improve their anti-collision performance.