• Journal of the Korean GEO-environmental Society
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• v.16 no.3
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• pp.41-48
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• 2015

Several sensor systems are used to estimate and predict the slope behaviors, however though slope sensing systems are much up-to-dated compared to before, they are mainly focused on the hardware developing. It means the analyzing software is deficient to apply the examining slope behavior for slope stability. In real case, slope behavior shows the 3-dimensional movement and failure; however the modeling methods for 3-D behavior are more difficult and need more variables. 1-D analysis shows only the length variation, however the real slope makes the 3-D behaviors. To fix the 3-D space coordinate, three values should be determined such as length, horizontal angle and vertical angle. Therefore if the 3-D coordinate system were composed by the points considered of two directions and length, the 3-D space could be separated into horizontal plane and vertical plane. The data from DY-slope in Chungbuk province was analyzed to the developed 3-D coordinate system. It is concluded from the results of 3-D analysis, the slope is generally moving to transverse direction, also the displacements are happening to road and vertical direction at the same time. Presently, the accumulated displacement between sensing points shows small value within 4.3 cm, and the displacements of all sensing points show the similar directions and magnitudes.

• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.5
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• pp.502-515
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• 2020

To identify the dynamic characteristics of the Auto-leveling system applied to the Tractor-Trailer type Transporter for mounting a large scale precision equipment, Dynamics Modeling & Simulation were performed using general Dynamics Analysis Program - RecurDyn(V9R2). The axial load data, transverse load data and pad trace data of leveling actuators were obtained from M&S. And they were analyzed and compared with each other by parameters, i.e. friction coefficients on the ground, landing ram speed of actuators, and direction & quantity of ground slope. It was observed that ground contact friction coefficients affected to transverse load and pad trace; the landing ram speed of actuators to both amplitude of axial & transverse load, and this phenomena was able to explain from the frequency analysis of the axial load data; the direction of ground slope to driving sequence of landing ram of actuators. But the dynamic behaviors on the two-directional slope were very different from them on the one-directional slope and more complex.

• Tunnel and Underground Space
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• v.27 no.2
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• pp.77-88
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• 2017

The geology of the study area is composed mainly of conglomerate, sandstone, and shale and basalt. It is a rock that has been observed to move relatively recently through various brittle deformation and various stress fields during the recent period. To form a gentle terrain with severe crushing. The slope is located at the intersection of the Taegok Fault in the north-northeast direction and the Bukok Fault in the western north-west direction, and many faults, fault zones and fracture zones of various sizes are developed in the rock bed. In this study, the geological characteristics of the slope are investigated and the countermeasure method is suggested. It is suggested that periodical measurement and analysis should be performed by installing a measuring instrument according to each structure for safety management of the surrounding roads and grounds during construction or reinforcement by the countermeasure method for the slope of the study area.

• Journal of the Korean Society for Railway
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• v.12 no.4
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• pp.548-556
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• 2009

In order to evaluate applicability of rock cut-slope investigation system, typical clinometer and photogrammetry investigation system were used for rock slopes; first for 7 discontinuities, and secondly, 10 discontinuities, and the results were compared. The first verification was performed depending on discontinuity joint shapes and slope angles, and the second verification was performed depending on shot time and shot locations. The results showed that differences of dip direction $1^{\circ}{\sim}4^{\circ}$, dip $0^{\circ}{\sim}4^{\circ}$. In the second verification test, the differences of dip direction was $0^{\circ}{\sim}6^{\circ}$, and dip $0^{\circ}{\sim}6^{\circ}$. The photogrammetry method for rock slope survey system is quite reliable when clinometer generally shows ${\pm}10^{\circ}$ errors due to surface roughness and investigator.

• Journal of the Korean Society for Nondestructive Testing
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• v.33 no.5
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• pp.430-435
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• 2013

This study is investigation of the characteristics for acoustic emission signal generated by destruction on glass fiber bundles and specimen that was machined composite materials surrounding the outside of GFRP cylinder. The Amplitude of acoustic emission signal gets bigger as the cutting angle of knife increases. Accordingly, the number of hits in destruction of composite materials specimen have more in longitudinal direction (longitudinal direction to the glass fiber) than in hoop direction (horizontal direction to the glass fiber) while the amplitude of signals were bigger in hoop direction than longitudinal direction. It was found out that the amplitude of the glass fiber breakage is more than 40 dB and that the amplitude of signal for matrix crack was less than 40 dB because matrix crack signal was not observed when threshold value is 40 dB and matrix crack signal suddenly appered when threshold value is 32 dB. The slope of the amplitude is related to the acoustic emission source and the slope of the amplitude of the horizontal and vertical directions are 0.16 and 0.08. In particular, The slope of the amplitude of longitudinal direction breakage appear similar to the glass fiber breakage and therefore Acoustic emission source of longitudinal direction breakage is estimated the glass fiber breakage.

• Korean Journal of Environment and Ecology
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• v.34 no.5
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• pp.425-435
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• 2020

This study aims to investigate the impact of the physical structure, such as altitude, slope gradient, slope direction, and topographical structure, and the vegetation pattern, such as existing vegetation, diameter of breast height (DBH), and crown density, on climate. The analysis results showed the significant difference in relative humidity, wind speed, and solar radiation at varying altitudes, the significant difference in all climate factors except for the wind speed at varying slope gradient, and significant difference in temperature and relative humanity at varying slope direction. The topographic structures were divided into valleys, slopes, and ridges. They were found to differ in relative humidity. However, the differences between constant trends and types were found to be insignificant concerning temperature, wind speed, and solar radiation. Significant differences in temperature, relative humidity, and wind speed were recorded with changing existing vegetation. The DBH showed a significant difference in temperature, wind speed, and solar radiation. The crown density showed a significant difference in temperature and solar radiation. The result of the relationship analysis for the analysis of the effect of vegetation pattern and physical structure on the meteorological environment showed that temperature was affected by slope gradient, slope direction, DBH, and crown density. The relative humidity was correlated with the altitude, slope gradient, slope direction, and topological structure in physical structure and the existing vegetation and crow density in vegetation pattern. The wind speed was correlated with the altitude, existing vegetation, and DHB, and the solar radiation was correlated with the slope gradient, DHG, and crown density. The crown density was the most overall significant factor in temperature, relative humidity, and solar radiation, followed by the slope gradient. DBH was also found to be highly correlated with temperature and solar radiation and significantly correlated with wind speed, but there was no statistically significant correlation with relative humidity.

• Journal of Environmental Science International
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• v.8 no.5
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• pp.633-637
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• 1999

A series of meterological observation using automation weather station(AWS) carried out to investigate characteristics of nocturnal meteorological parameters for 16~17 June 1998 at Buljeongdong mountain slope, Kyungbuk. Dry temperature at valley was lower than mountain because of high lapse rate at valley, so the strong inversion layer occurrenced at mountain slope for nighttime. Contrary of dry temperature, relative humidity of valley was higher than mountain for nighttime. Wind speed at valley from sunset to next day morning was lower than mountain, but that of valley after sunrise was higher than mountain. Wind direction at valley for all observation time were southeasterlies(SE), that of mountain for nighttime were northeasterlies(NE) or northnorthwesterlies(NNW), and that of mountain after sunrise were irregular. Vapor pressure at valley for all observation time was higher mountain, particularly the difference was high for nighttime.

• Journal of Korea Water Resources Association
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• v.45 no.7
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• pp.643-656
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• 2012

There has been an increase for the landslide areas and restoration expenses due, in large part, to the increased locally heavy rains caused by recent climate change as well as the reckless development. This study carried out a slope stability analysis by the application of distributed wetness index, using the GIS-based infinite slope stability model, which took the root cohesion effect into consideration, for part of Mt. Umyeon in Seoul, where landslide occurred in July 2011, in order to compensate the defects of existing analysis method, and subsequently compared its result with the case on the exploitation of lumped wetness index. In addition, this study estimated the distributed wetness index by methodology, applying three methods of specific catchment area calculation: single flow direction (SFD), multiple flow direction (MFD), and infinity flow direction (IFD), for catchment area, one of the variables of distributed wetness indices, and finally implemented a series of comparative analysis for slope stability by methodology. The simulation results showed that most unstable areas within the study site were dominantly located in cutting-area surroundings along with the residential area and the mountaintop and unstable areas of IFD and lumped wetness index method were similar while SFD and MFD provided smaller unstable areas than the two former methods.

• Journal of the Korean Geotechnical Society
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• v.23 no.6
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• pp.97-102
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• 2007

Though the stability analysis of soil slopes widely employs the limit equilibrium method, the study on the jointed rock slopes must consider the direction of joint and the characteristics of Joint at the same time. This study analyzes the result of the change in the factors which show the characteristics of discontinuity and the shape factor of rock slopes, and so on, in an attempt to validate the propriety as to the interpretation of jointed rock slope stability which uses the general finite element program. First, the difference depending on the flow rules was compared, and the factor effect study was conducted. The selected independent variables included the direction of joint which displays the mechanical characteristics of discontinuity, adhesive cohesion, friction angle, the inclination and height of rock slope which reveal the shape of slope and surcharge load. And the horizontal displacement was numerically interpreted at the 1/3 point below the slope, a dependent variable, to compare the relative degree of factor effects. The findings of study on factor effects led to the validation that the result of horizontal displacement for each factor satisfied various engineering characteristics, making it possible to be applied to stability interpretation of jointed rock slope. A modelling is possible, which considers the application of the result of real geotechnical surveys & laboratory studies and the non-linear characteristics when designing the rock slope. In addition, the stress change which may result from the natural disaster, such as precipitation, and the construction, can be expressed. Furthermore, as the complicated rock condition and the ground supporting effect can be considered through FEM, it is considered to be very useful in making an engineering decision on the cut-slope, reinforcement and so on.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.2
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• pp.12-20
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• 2004

This study was carried out from January 1998 to December 1999 to report the revegetation of cutting-rock slopes and a design standard in the highway cut-slopes. The field data was collected from the 67 sites cutting-rock slopes of highways, local roads, and field test. As the result of analyze, cutting-rock slopes revegetation measures were 16 types. There were Vine planting(3 types), Hydroseeding measures with seed-fertilizer-soil materials(5 types), Vegetaion-base spraying measures(5 types), and Stability measures(3 types). The factors affecting the plant coverage rates of cutting-rock slopes were the slope gradient, the slope width and direction. The plant coverage rate decreases in the condition of steep slope and long slope width and length(height). In addition, the plant coverage rates of the westward and southward were lower than that of the northward and eastward. Most dominant species were Zoysia japonica, Lespedeza cyrtobotrya, Lespedeza cuneata, Rubus crataegifolius, Miscanthus sinensis, Arrundinella hirta, Themeda triandra, and Oenothera odorata. Exotic species were Eragrostis curvula(Weeping lovegrass), Dactylis glomerata Orchardgrass), Lolium perenne(Perennial ryegrass), and Festuca arundinacea(Tall fescue). It is recommended to adjust the proposed factor as environment, topsoil, classification of rock, field condition and characteristic related with revegetation measures on slopes for the presentation of revegetation standard.