• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.427-435
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• 2008

A reliability based slope stability assessment method is proposed and examined considering the variation of matric suction which is measured by a real time slope monitoring system. Mean value first order reliability method and advanced first order reliability method are used to calculate reliability indices of a slope. The applicability of methods is compared by applying them to the range of matric suctions measured by the real-time monitoring system. Sensitivity analysis is also performed to examine the contribution of random variables to the reliability index of slope. Finally, the proposed method is applied to a model slope. The results show that the reliability index of slope can be used for efficient slope management by quantifying the risk of slope in real time.

• International journal of advanced smart convergence
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• v.10 no.1
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• pp.184-196
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• 2021

This study, in order to evaluate the safety of evacuation by comparing and analyzing the RSET according to the slope change of the ramp, which is a vertical evacuation route in case of fire in a high school building, Evacuation simulation was run the Pathfinder program changed the slope of the ramp to 10°, 15°, and 20° for each male students and female students. In the case of female students, it was analyzed that when the final RSET slope was 15°, 25.7 seconds were shorter than when 10°, and 4.2 seconds were shorter than when 20°. Male students also found that when the final RSET slope was 15°, 23.8 seconds were shorter than when 10°, and 5.4 seconds shorter than when 20°. It was analyzed that even if the number of participants was increased and the evacuation simulation was executed, the safety of evacuation could be improved when the slope of the slope is 15° as the RSET when the slope of the slope is 15° is shorter than that of 10° and 20°.

• The Journal of Engineering Geology
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• v.16 no.2 s.48
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• pp.189-199
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• 2006

This paper presents a field study of the stability of slope collapsed during road construction and proposes a reasonable countermeasure if the current slope is unstable. As a result of slope investigation, it was found that the slope includes five tension cracks and the sliding surface is started from the tension crack and propagated the surface soil layer through weathered rock layer. The slope stability analyses are conducted in case of dry and rainfall seasons. The results indicate that the slope is unstable status. A reinforcement method of slope failure should be selected according to the scale of failure. That is, the scale of slope failure, which is classified small, middle and large size determines the reinforcement method of slope. Since the slope interested in this study is large size failure slope, the reinforcement method to control slope failure is selected stabilizing piles, and seed spray and drainage of surface waterare also selected to remain the factor of safety. The SLOPILE (Ver. 3.0) program is applied in order to do stability analysis of slope reinforced by piles. As the result of analysis, the slope reinforced by a row of piles shows the stable state. It is clearly confirmed that the stabilizing of piles can improve the stability of slope.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.4
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• pp.273-281
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• 2008

In this study, the effect of slope length and angle at the entrance to fishing pots on the size of captured shrimp was examined to determine the optimal design of pots for use in Hokkaido, Japan. The purpose of the current study was to optimize the design of shrimp pots to allow greater control over the size of captured individuals for the purposes of shrimp resource management. Tank experiments were conducted to determine the optimal slope length and slope angle by analyzing the sizes of shrimp entering 10 model pots with combinations of five different slope lengths on slope angle of current shrimp pot, and five different angles on slope length of current shrimp pot. The results showed that, as the slope length of the pot increased, the size of individuals which entered the pot increased. In addition, as the slope angle was elevated in each of the five different slope angle treatments, the size of individuals entering was also increased.

• Journal of the Korean Geosynthetics Society
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• v.8 no.4
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• pp.47-51
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• 2009

The slope failure in the country is caused by mainly rainfall and its type is reported shallow slope failures in general. To investigate the cause of slope failure, the unsaturated soil slope behavior in accordance with rainfall amount studies actively, but there are little studies related the slope erosion and scour by rainfall. The slope erosion and scour by rainfall cause environmental pollution and slope instability, however there are few methods to effectively control them. This research analyzed experimentally how infinite gradients are infiltrated according to the changes of amount of rainfall and the slope of gradients by manufacturing the model of gradient in order to investigate how rainfall infiltrates regarding homogeneous gradients and slope protection method. For this, this experiment measured and analyzed discharge, storage rate occurring in gradients by going on changing amount of rainfall, slope of gradients.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.179-184
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• 2005

Shear strength parameters obtained from filed survey are important factors in the analysis of slope stability. In this study, sensitivity analysis was performed to evaluate the effect of input parameters on the analysis of slope stability. The input parameters selected for sensitivity analysis were slope angle, cohesion, and friction angle. Monte-Carlo Simulation method was used for calculating input parameters and the factor of safety was computed by means of limit equilibrium method. A rock slope, which has failed in the field, was used for the sensitivity analysis in the analysis of slope stability. The result of analysis shows that the factor of safety of the rock slope was a little low. From partial correlation coefficient(PPC) of input parameters determined from the sensitivity analysis, slope stability was dependant on cohesion and slope angle. The effect of friction angle was lower than that of cohesion and slope angle on slope stability.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.4
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• pp.41-52
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• 2013

This study was carried out in order to analyze the succession characteristics of the slope of expressways and the results of analysis by collecting and analyzing various literatures and data from 2011 to 2012 and surveying 75 expressway slope, as follows : The construction methods applied to planting the slope of an expressway can be classified into 4 types including 3 Climber planting methods, 8 Vegetation thick-layer spray work methods, 4 Seed spray work methods, and 4 Stabilization work methods. The factors which affect the cover degree of the slope of an expressway were found to be development years, gradient, length, and azimuth. Like surrounding forest areas, the expressway slope was analyzed to begin the plant succession 20, 30, and 40 years after development, and plant succession was developed in diversity in a mixed stand forest according to surrounding forest floors. Species diversity, maximum species diversity, and the evenness of slope facing north were analyzed to be high comparing to those facing east, west, and south according to azimuth of slope. Species diversity, maximum species diversity, evenness of slope, and the plant succession of surroundings were analyzed to be high when the gradient of the slope was less than $40^{\circ}$. The dominant species which success on the slope of an expressway and its surrounding forest area included Miscanthus sinensis var. purpurascens, Zoysia japonica, Pinus thunbergii Parl, Rubus crataegifolius, Lespedeza cyrtobotrya, Amorpha fruticosa, Artemisia princeps var. orientalis, and Oenothera biennis.

• Magazine of the Korean Society of Agricultural Engineers
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• v.31 no.1
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• pp.58-70
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• 1989

The paper compared the Bishop methed to the Fellenius method in the analysis of slope stability. Laboratory model test was carried out in the case of seepage flow considered. The results obtained from this study were summarized as follows; 1. The slice pieces of 10 were enough to analysis the slope stability. 2. The safety factor. by the Fellenius method was lower than the Bishop method by the 96 to 97% in the case of no seepage flow and by the 95 to 96% in the case of seepage flow considered. 3. Besides the parameter of soil and slope, the safety factor of slope was influenced by the height of slope. This phenomena was distinct in the height of height less than 10 meters. 4. In the case of clay, there was no difference in the safety factor of slope between Fellenius and Bishop rnethod. The safety factors of slope with the seepage flow considered were lower than those with no see-page flow. 5. The influence of cohesion on the safety factor was more significant in the Bishop method than in the Fellenius method. 6. The slope failure of model test of A and B soil samples with high permeability coefficient was taken place slightly in vicinity of toe by the concentration of stress and gradually increased 7. Under condition of same slope height, the shapper the slope, the shorter the radius and the center of critical circle appered downward and finally failure of slope occured inside the slope.

• Journal of the Korea institute for structural maintenance and inspection
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• v.4 no.1
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• pp.101-110
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• 2000

In case heavy rainfall is a key factor of slope failure, the failure zone is usually developed within the depth of 3~5m from the ground surface regardless of the location of the watertable. If rainfall is taken into consideration, it is general that the slope stability analysis is carried out under the assumption that the cut slope is saturated to the slope surface or the watertable elevates to a certain height so that ${\gamma}_{sat}$, the unit weight of saturated soil, is used. However, the analysis method mentioned above can't exactly simulate the variation of pore water pressure in the slope and yields different failure shape. The applicability of slope stability analysis method considering the distribution of pore water pressure within the slope with heavy rainfalls, was checked out after the stability analysis of a lage-scale cut slope in a highway construction site, where surface failure occurred with heavy rainfalls. An appropriate slope stabilization method is proposed on the base of the outcome of the analysis.

• Communications for Statistical Applications and Methods
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• v.12 no.1
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• pp.253-264
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• 2005

Hader and Park(l978) suggested the concept of slope-rotatability in axial directions for second order response surface designs. In this paper, the moment conditions for slope-rotatability in axial directions are shown and the measures for evaluating slope-rotatability in axial directions are proposed.