• Journal of Navigation and Port Research
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• v.32 no.3
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• pp.251-255
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• 2008

Container cranes are vulnerable structure about difficult weather conditions bemuse there is no shielding facility to protect them from the strong wind. This study was carried out to analyze the wind load which have an effect on container crane according to the various wind direction. The container crane is a model of a 61-ton class that used broadly in the current ports. The external fluid field was figured as a cylinder which was set up $500m{\times}200m$. In this study, we applied mean wind load conformed to 'Design Criteria of Wind Load' in 'Load Criteria of Building Structures' and an external fluid field was divided as interval of 10 degrees to analyze effect according to a wind direction In this conditions, we carried out the computation fluid dynamic analysis using the CFX-10. As we compared computation fluid dynamic analysis with wind tunnel test, we analyzed the wind load which was needed to design the container crane.

• Journal of Navigation and Port Research
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• v.33 no.3
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• pp.215-220
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• 2009

Container cranes are vulnerable structure to difficult weather conditions bemuse there is no shielding facility to protect them from strong wind. This study was carried out to analyze the effect of wind load on the structure of a container crane according to the change of the boom shape using wind tunnel test and computation fluid dynamics. And we provide a container crane designer with data which am be used in a wind resistance design of a container crane assuming that a wind load 75m/s wind velocity is applied in a container crane. In this study, we applied mean wind load conformed to 'Design Criteria of Wind Load' in 'Load Criteria of Building Structures' and an external fluid field was divided as interval of 10 degrees to analyze the effect according to a wind direction. In this conditions, we carried out the wind tunnel test and the computation fluid dynamic analysis and than we analyzed the wind load which was needed to design the container crane.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2006.06b
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• pp.349-354
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• 2006

This study analyzed the fluid state around a container crone according to a wind direction when a wind load was applied to a container crone. The container crane for this research is a model of a 50-ton class used broadly in the current ports. The dimension of an external fluid field set up diameter, 300m, height, 200m. This study considered the change of a wind velocity according to an altitude in a criterion of a wind velocity, 50m/s, applying a power series law. An incident angle applied to an interval of 30 degrees in $0^{\circ}{\sim}180^{\circ}$ and this study carried out a computation fluid dynamics using a CFX-10. In this study, we indicate the wind pressure according to the height and section figure of each member. In addition, we suggest the wind pressure accordint to a wind direction. And we will analyze the structure stability of a container crone from the fluid-ductile analysis in the next study.

• Journal of Navigation and Port Research
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• v.38 no.5
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• pp.463-470
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• 2014

In this paper, calculation of towing force required to tow the ship and experiments to verify its appropriacy are discussed. Friction, wind and wave-making resistance of vessel are considered to calculate towing force of specified vessel. Propeller resistance is also reflected and it is assumed that the propellers are locked. Node analysis to estimate additional resistance on towline is applied. Total towing force could be obtained by adding the ship's resistance and towline resistance. Experiments with training ship SAE YU DAL was executed to check the effectiveness of calculation methods and some comparison between experiments and calculation results was also done. From the comparative analysis, we confirmed that towing speed is primary terms in the calculation of towing force and propeller resistance is a major elements of ship's resistance with the increasing of towing speed. We can see that additional resistance induced by yawing of ship during towing have to be considered for total tow resistance.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.2
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• pp.331-346
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• 2018

In the tunnel of domestic high - speed railway, the main fire - fighting facility, fire - extinguishing passageway, is installed. However, due to the high pressure of the high - speed train, frequent breakage and maintenance are caused by strong shock and long - term vibration. In order to solve these problems, it is necessary to improve the fire door, but in Korea, it is installed by submitting a certificate by simple KS F 2296 performance test. At present, it is developed as a simple test certification by producing a real scale fireproof door without the theoretical examination in advance, so that a high cost for improvement is occurring in Korea. Therefore, through this study, structural analysis study which can preliminary structure review was carried out in order to design the refuge connection passage fire door and to improve the performance improvement. In order to secure the reliability of the result value, the official authentication test (KS F 2296) were compared.

• Journal of Korean Society of Steel Construction
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• v.19 no.2
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• pp.223-231
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• 2007

Considering wind speed uncertainty, reliability analysis of the LNG unloading arm at Tongyoung Production Site was performed. Extreme distribution of wind speed was estimated from the data collected at the weather center and wind load was calculated using wind velocities and coefficients of wind pressure. The unloading arm was modeled with plate and solid elements. Contact elements were used to describe the interface between base of structure andground. Response surface for maximum effective stress was found for reliability analysis and then reliability functions was defined and used to determine exceeding probability of allowable and yield stresses. In addition, sensitivity analysis was also performed to estimate the effect of possible material deterioration in the future.

• Journal of Bio-Environment Control
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• v.24 no.3
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• pp.135-146
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• 2015

To provide the data necessary to determine the design wind speed for calculating the wind load acting on a greenhouse, we measured the wind speed below 10m height and analyzed the power law exponents at Buan and Gunwi. A wind speed greater than $5m{\cdot}s^{-1}$ is appropriate for calculating the power law exponent necessary to determine the wind speed distribution function according to height. We observed that the wind speed increased according to a power law function with increased height at Buan, showing a similar trend to the RDC and JGHA standards. Therefore, this result should be applied when determining the power law function for calculating the design wind speed of the greenhouse structure. The ordinary trend is that if terrain roughness increases the value of power law exponent also increases, but in the case of Gunwi the value of power law exponent was 0.06, which shows contrary value than that of the ordinary trend. This contrary trend was due to the elevations difference of 2m between tower installed and surrounding area, which cause contraction in streamline. The power law exponent started to decrease at 7 am, stopped decreasing and started to increase at 3 pm, and stopped increasing and remained constant at 12 pm at Buan. These changes correspond to the general change trends of the power law exponent. The calculated value of the shape parameter for Buan was 1.51, confirming that the wind characteristics at Buan, a reclaimed area near the coast, were similar to those of coastal areas in Jeju.

• Journal of Korean Association for Spatial Structures
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• v.6 no.1 s.19
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• pp.83-90
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• 2006

The GF(Gust Factor) method is usually used as a method to evaluate equivalent static wind loads for general structures. The GF method is performed on the assumption that the shape of the equivalent static wind load profile is typically similar to that of mean wind loads. The shape of fluctuating wind loads could be quite different with that of the mean wind loads in case of large-span structures. So, the effect of higher modes as well as first mode must be considered to evaluate the wind loads. In this study, the ACS (Advanced Conditional Sampling) method is suggested to evaluate of equivalent static wind loads after investigating about GF and LRC method. The An method ran derive effective static wind loads by combining wind pressures and inertia forces of a structure chosen at a maximum load effect. The maximum load effect is assessed with the time history analysis using pressure data measured in wind tunnel tests. Equivalent static wind loads evaluated using ACS, GF, and LRC methods are compared to verify the effectiveness of ACS method.

• Journal of Navigation and Port Research
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• v.31 no.5 s.121
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• pp.345-351
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• 2007

In approaching sea area of Busan harbour, there are many traffic vessels and external forces such as strong seasonal wind and lateral flow are existed. Since the area caused the risk of navigation and ship operators feel hard to enter/depart on Busan port, we carried our the evaluation of traffic risk and propriety at Busan no.1 fairway. In order to assess the safety in the fairway, we analyzed ship's traffic stream based on the marine traffic survey and evaluated the traffic safety of present Traffic Separation Schemes(TSS) and suggest TSS in the research using full mission ship-handling simulators. As a result, the suggested TSS has an effect on improving the traffic safety. In addition, this paper was to suggest the dredging area of depth of water, the passage of towing vessels and control of warships for preventing of maritime accidents in the Busan no.1 fairway.

• Journal of Korean Tunnelling and Underground Space Association
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• v.16 no.3
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• pp.269-285
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• 2014

In spite of the importance of the natural ventilation pressure(NVP) in tunnels for the optimal design of the ventilation system, there have been only few studies on the NVP because its measurement and quantitative analysis are not straightforward. This study aims at quantifying the amount of the NVP with the terrain and meteorological data for the local major tunnels. And ultimately this will lead to developing the guidelines for quantifying and applying NVP for the optimal design of tunnel ventilation system. 22 local tunnels in the major routes are studied for the NVP quantification. NVP derived from the meteorological data is in the range of 20~140 Pa, while NVP estimated from the terrain data ranges from 20 to 200 Pa. Since the jet fan pressure is about 10~15 Pa per unit, the minimum level of NVP expected in the local tunnels is larger than the pressure rise by one unit of the ordinary jet fan. This implies that NVP in local tunnels should be quantified and be taken into consideration for the economic and safe ventilation design. The barometric pressure difference between tunnel portals is found to be the most influential factor, accounting for 61% of the NVP, while the wind pressure acting on the portals and the chimney effects occupy 22% and 17%, respectively.