• Earthquakes and Structures
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• v.6 no.2
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• pp.163-179
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• 2014

Dynamic test with scaled model of a group of intake towers was performed to study the dynamic interaction between water and towers. The test model consists of intake tower or towers, massless foundation near the towers and part of water to simulate the dynamic interaction of tower-water-foundation system. Models with a single tower and 4 towers were tested to find the different influences of the water on the tower dynamic properties, seismic responses as well as dynamic water-tower interaction. It is found that the water has little influence on the resonant frequency in the direction perpendicular to flow due to the normal force transfer role of the water in the contraction joints between towers. By the same effect of the water, maximum accelerations in the same direction on 4 towers tend to close to each other as the water level increased from low to normal level. Moreover, the acceleration responses of the single tower model are larger than the group of towers model in both directions in general. Within 30m from the surface of water, hydrodynamic pressures were quite close for a single tower and group of towers model at two water levels. For points deeper than 30m, the pressures increased about 40 to 55% for the group of towers model than the single tower model at both water levels. In respect to the pressures at different towers, two mid towers experienced higher than two side towers, the deeper, the larger the difference. And the inside hydrodynamic pressures are more dependent on ground motions than the outside.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09b
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• pp.13-20
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• 2010

This paper presents the results of a numerical investigation on the ground deformation in deep excavation with emphasis on the groundwater lowering. Using the stress-pore pressure coupled analysis Consideration to the effect of ground excavation and groundwater interaction were carried out and a series of two-dimensional finite element model was employed to perform a parametric study on a wide range of soil profile and initial ground water table condition.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.7 s.100
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• pp.806-812
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• 2005

This paper adresses the shaking table tests with 1/100 scaled model followed similitude law for OOdam main designing section to understand nonlinear behavior characteristics of concrete dam body by ground motion. As earthquake wave, Hachinohe and El Centre waves were used and acceleration and displacements are measured to analyze behaviors of dam body. For maximum ground acceleration range $(0.3\~0.9 g)$, the results showed linear behavior regardless of maximum 9round acceleration and secured safety of structure. To analyze the behavior of dam after tension cracking, 3 cm-notch was placed at the critical section of over-flowing section. As results of applying Hachinohe wave(0.8 g), Even though tension cracks were formed at over-flowing section by Hachinohe wave(0.8 g), it showed that the dam is stable for supporting upper stream Part of water tank of dam.

• International journal of steel structures
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• v.18 no.4
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• pp.1167-1176
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• 2018

Steel cylindrical tanks are widely used for the storage of hazardous substances of which leakage must be prevented under any circumstances. However, the dynamic response of the steel cylindrical liquid storage tank depends sensitively on the fluid-structure interaction and the vibration of the tank structure and necessitates clarification for the safety of the tank structure. This paper presents the results of shaking table tests performed to examine the dynamic behavior of a scaled cylindrical steel tank model considering the presence or not of fixed roof and added mass at the top of the tank for various fluid levels. The test results confirm the occurrence of both beam-type and oval-type vibration modes and show that the larger content of liquid inside the container amplified the acceleration along the height of the cylindrical tank. The oval-type vibration modes are seen to be more dominant in case of large water-to-structure mass ratio.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.323-327
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• 2006

During the past decades in South Korea, there have been several projects to reduce water demand and save water for paddy irrigation system by automation. This is called as intensive water management system by telemetering of paddy ponding depth and canal water level and telecontrol of water supply facilities. This study suggests a method of constructing topology-based irrigation network system using GIS tools. For the network modeling, a typical agricultural watershed included reservoirs, irrigation and drainage canals, pumping stations was selected. ArcHydro tools composed of edge, junction, waterbody and watershed were used to construct hydro-network. ArcHydro Model was then designed and the network was successfully built using the HydroID. Visualization using ArcHydro tools could display table property of each object. ArcHydro Model was linked to Agricultural Water Demamd and Supply Estimation System (AWDS) which developed by Korea Rural Community and Agriculture Corporation (KRC) to extract information of the study area. And menu of supply facilities information, demand analysis and supply analysis constructed for information acquisition and visualization of acquired informations.

• Journal of Korean Society on Water Environment
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• v.32 no.6
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• pp.582-588
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• 2016

The hydrological simulation program FORTRAN (HSPF) is a comprehensive watershed model that employs the hydraulic function table (FTABLE) (depth-area-volume-flow relationship) to represent the geometric and hydraulic properties of water bodies. The hydraulic representation of the HSPF model mainly depends on the accuracy of the FTABLES. These hydraulic representations determine the response time of water quality state variables and also control the scour, deposition, and transport of sediments in the water body. In general, FTABLES are automatically generated based on reach information such as mean depth, mean width, length, and slope along with a set of standard assumptions about the geometry and hydraulics of the channel, so these FTABLES are unable to accurately describe the geometry and hydraulic behavior of rivers and reservoirs. In order to compensate the weakness of HSPF for hydraulic modeling, we generated alternate method to improve the accuracy of FTABLES for rivers, using the surveyed cross sections and rating curves. The alternative method is based on the hydraulics simulated by HEC-RAS using the surveyed cross sections and rating curves, and it could significantly improve the accuracy of FTABLES. Although the alternate FTABLE greatly improved the hydraulic accuracy of the HSPF model, it had little effect on the hydrological simulation.

• 한국지구물리탐사학회:학술대회논문집
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• 2001.09a
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• pp.94-103
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• 2001

An experiment was conducted using a sand and gravel-filled tank model, to investigate the influence on the GPR response of vadose zone gasoline vapor phase effects and residual gasoline distributed by a fluctuating water table. After background GPR measurements were made with only water in the tank, gasoline was injected into the bottom of the model tank to simulate a subsurface discharge from a leaking pipe or tank. Results from the experiment show the sensitivity of GPR to the changes in the moisture content and its effectiveness for monitoring minor fluctuation of the water table. The results also demonstrate a potential of GPR for detecting possible vapor phase effects of volatile hydrocarbons in the vadose zone as a function of time, and for detecting the effects of residual phase of hydrocarbons in the water saturated system. In addition, the results provide the basis for a strategy that has the potential to successfully detect and delineate LNAPL contamination at field sites where zones of residual LNAPL in the water saturated system are present in the subsurface.

• Transactions of Materials Processing
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• v.12 no.4
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• pp.302-307
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• 2003

Hot rolled strip is cooled by air and water in Run-Out-Table. In this process, phase transformation and shape deformation occurs due to temperature drop. Because of un-ideal cooling condition of ROT, irregular shape deformation and phase transformation arise in the strip. which affect the strip property and lead to the residual stress of strip. And these exert effects on the following processes, coiling process, coil cooling process, and re-coiling process. Through these processes, the residual stress becomes higher and severe. For the prediction of residual stress distribution and shape deformation of final product, Finite element(FE) based model was used. It consists of non-steady state heat transfer analysis, elasto-plastic analysis. thermodynamic analysis and phase transformation kinetics. Successive FEM simulation were applied from ROT process to coil cooling process. In each process simulation, previous process simulation results were used for the next process simulation. The simulation results were matched well with the experimental results.

• Journal of the Korean Geosynthetics Society
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• v.17 no.3
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• pp.33-46
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• 2018

This study presents the experimental results on the performance of deep excavation by using image processing technique particle image velocimetry (PIV). The purpose of present study is to be checked the application of PIV for the successive ground deformation during deep excavation. To meet the objectives of concern study, a series of reduce scale model test box experiments were performed by considering the wall stiffness, ground water table effect and ground relative density. The results were presented in form of contours and vector plot and further based on PIV analysis wall and ground displacement profile were drawn. The results of present study, indicate that, the PIV technique is useful to demonstrate the ground deformation zone during the successive ground excavation.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.352-358
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• 2005

This study aims to separate hydrograph into baseflow and event water to calculate baseflow rate during a rainfall in small catchments, Yuseong, Daejeon, The hydrograph of stream during a period with no excess rainfall will decay. The discharge is composed entirely of groundwater contributions. During the period, the Cl concentration of the stream water can be regarded as being in equilibrium with that of the groundwater. Using Cl as a conservative tracer, two-component hydrograph separations were performed from end point of the period to next end point. The required data were obtained by monitoring of the surface water table, along with discharge rate of stream. Cl concentration of rainfall, surface water were measured and recorded. Hydrograph separation, a mixing model using chemical tracer is applied to chemical hydrograph separation technique. These results show that baseflow rates are 31.6% of rainfall in the catchments during study period.