• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.581-584
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• 2008

This study analyzed activity of rockfall and its effect factor by the shape and mass. We performed research on the kinetic energy distribution, velocity and bounce height according to the rockfall characteristics using rockfall simulation program in cut-slope. In addition, this study discussed how to utilize kinetic energy and bounce height of rockfall for efficient establishment of rockfall prevention fence which is a countermeasure to cut-slope.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.412-418
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• 2008

This study area show the complicated geological figure and some developed small fault area in southern of Korea. Because of insufficient investigation and design for the big slope, even the safety analysis by the specific institution, in the event, there were 6 times failure and 6 time safety analysis. After all, The height and remedial work cost of the slope became much bigger then early stage.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.2
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• pp.211-218
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• 1993

Landslides, failure of slope stability by natural or artificial factors, occur loss of life and properties. Recently, statistical methods and field measurements are used to a study for prediction of landslide harzard area, but there are so many difficulties to find the occurence system because of its complexity. In this study, authors choose the model area where occured landslides to predict the landslide hazard. Authors made a database of ground height to compare the each topography by scale of 1 : 25,000, 1 : 10,000, 1 : 5,000 and 1 : 1,200. Authors predict to landslide hazard area by the weight of ground height data and slope angle data. Finally, authors could know the possibility of prediction to find the landslide hazard partly.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.3
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• pp.440-447
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• 2012

Numerical model experiments of wave transformation due to the reclamation and the construction of breakwater in case of 50 years design wave were performed using time dependent mild slope equation included shoaling, refraction, diffraction, reflection and wave breaking. As waves propagate to the shore, wave height gradually diminishes by the bottom friction and wave breaking etc.. After the reclamation and the construction of 75 m length breakwater, wave height distributions in the lee of breakwater have the range of 29~128 cm. To make better the harbor tranquility the length of breakwater needs to extend more than 100 m. After the construction of breakwater, wave height in the lee of the structure was deduced over 80%.

• Wind and Structures
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• v.31 no.3
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• pp.185-196
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• 2020

A method to reduce the wind pressure at the leading edge of a noise barrier was investigated by gradually lowering the height of a member added to the end of the noise barrier. The shape of the lowered height of the added member was defined by its length and slope, and the optimal variable was determined in wind tunnel testing via the boundary-layer wind profile. The goal of the optimal shape was to reduce the wind pressure at the leading edge of the noise barrier to the level suggested in the Eurocode and to maintain the base-bending moment of the added member at the same level as the noise-barrier section. Using parametric wind tunnel investigation, an added member with a slope of 1:2 that protruded 1.2 times the height of the noise barrier was proposed. This added member is expected to simplify, or at least minimize, the types of column members required to equidistantly support both added members and noise barriers, which should thereby improve the safety and construction convenience of noise-barrier structures.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.7 no.2
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• pp.135-140
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• 1995

The procedure of wave energy dissipation due to breaking has been investigated with trains of the regular wave. To obtain the data for wave breaking and its deformation, experiments have been conducted by utilizing a horizontal step adjoining to a combined slope of 1/20 and 1/10. After breaking the wave height decreases by dissipation but attains a stable value at some distance from the breaking point Experimental results show that the stable wave is considerably affected by the wave period. The study gives the general form of stable wave height A new one-dimensional wave deformation model is proposed. being coupled with an approximated shoaling coefficient before wave breaking and the new energy dissipation term after breaking. It was compared with the experimental data. It predicts well the wave height deformation before and after wave breaking even on the abrupt change of the depth.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.2_2
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• pp.245-254
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• 2020

This study investigated the so far little-researched characteristics of the behaviors of rock slopes at the time of an earthquake. For the selection of the rock block, a proper model was formed by applying the similarity in consideration of the roughness and strength of the rock slope(10m) on the site, and shaking table tests were carried out according to seismic excitement acceleration, and seismic waves. In the case of the inclination angle of the joint plane of 20°, the long period wave at 0.3g or more at the time of the seismic excitement surpassed the length of 100mm, the permissible displacement (0.01H, H:slope height), which brought about the collapse of the rock; the short period wave surpassed the permissible displacement at 0.1g, which caused the collapse of the slope. The rock slope was close to a rigid block and a structure more vulnerable to the long period wave than to the short period wave. It collapsed in the short period wave even at the seismic amplitude smaller than the maximum design acceleration in Korea.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.145-152
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• 2005

Landslides triggered by rainfall produces severe effects on the serviceability and stability of railway operation. Since small amount of soil mass slipped on the rail can cause derailment which will cause severe danger on the human and trains, slope stability problem is one of the major concerns on the operation of railway. In this study we investigate the some of characteristics of rainfall driven landslide near railroad. A total of 23 sites were visited. From the results four types of landslides based upon the morphology of the slipped slope triggered by rainfall were classified. From the analysis dimensions of slopes (height, length and slope) do not show particular correlation with the types of landslides. In addition, morphological and geological features of slope influence on the occurrence of different types of landslides.

• The Journal of Engineering Geology
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• v.10 no.2
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• pp.1-17
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• 2000

In this study, 270 cut-slopes are investigated and statistical analyses are performed. More than 84% of unstable slopes are rock slopes or rock-soil mixed slopes, and 72% of the slopes have 10 to 30 meter in height. And in order to clarify the cause of failure, 3 slopes which have been failed are back-analysed by using the computer programs such as DIPS, UDEC and PCSTABL5M. A heavy rainfall during rainy season is a main cause of slope failure, and a blasting vibration during construction could also give a significant influence on the slope instability.

• Tunnel and Underground Space
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• v.5 no.2
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• pp.104-113
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• 1995

Shear strength of the discontinuity on which the pre-failure of rock slope was occurred during surface excavation was measured through the direct shear test using core samples obtained in-situ. Internal friction angle was increased as the roughness of discontinuity surface(JRC) was increased. Results of the tilt test using core samples of higher JRC also showed very similar trend as those of the direct shear test. When the samples replicated from natural cores were used int he tilt test, results of friction angles showed almost perfect continuation of the residual friction angles from the direct shear test. However, when the gouge material existed in the discontinuity the internal friction angle strongly depended upon the rate of filling thickness to the height of asperity irrespective of the JRC. Based on the results of both direct shear test and tilt test internal friction angle and cohesion of discontinuity, which reflect the in-situ conditions fo pre-sliding failure and also can be used for the optimum design of support system, were assessed. Two kinds of support measures which were expected to increase the stability of rock slope were considered; lowering of slope face angle and installation of rock cable. But, it was found that the first method might lead to more unstable conditions of rock slope when the cohesion of discontinuity plane was negligibly low and in that case the support systems of any kind which could exert actual resisting force were needed to ensure the permanent stability of rock slope.