• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.1076-1085
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• 2009

Recent heavy rains and typhoons broke down road slopes, which caused a hazard to safety. As a result, interests in the effective investment for disaster prevention is increasing. Measures of investigation method for slope have been taken, but the financial costs have never been analysed. This study applied the cost-benefit analysis theory used in public economics to the evaluation of the financial reasonability of management for slope. By applying cost-benefit analysis to road slope investigation method, the reduction of safety costs and resulting financial benefits can be seen and it also clarifies the reasonability and investment effects of slope management.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.984-991
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• 2008

In this study, to evaluate the slope and tunnel stabilization method using pc cable with bulbed. To estimate the application of tunnel support using field tests and numerical analysis results. The reinforcement effects of slope stabilization method reinforced by PC cables were estimated compared with conventional soil nail system that reinforce the slope using rebar.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.4
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• pp.71-77
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• 2010

Cut Slope Management System(CSMS) is a systematic maintenance and management system designed to prevent the collapse of cut slopes located along national roads. In order to implement safe road operation system, KICT has started the inventory of cut slopes and developed a cut slope database since 2006. Cut slope database management system using GIS technology and navigation system was developed as a Information Technology application. Through the Cut Slope Navigation System(SLOPE-Navi.), the previously developed database was checked and verified. The converted cut slope inventory data and field investigation data of 28,707 cut slopes were loaded on the navigation map. We consider that the Cut Slope Navigation Management System can be useful as in-situ system, which can be systematic and effective DB management and operation to prevent cut slope collapses and establish a remedial countermeasure as mitigation concerning disasters.

• Geomechanics and Engineering
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• v.23 no.1
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• pp.15-30
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• 2020

The probabilistic bearing capacity of a strip footing placed on the edge of a purely cohesive reinforced soil slope is computed by combining lower bound finite element limit analysis technique with random field method and Monte Carlo simulation technique. To simulate actual field condition, anisotropic random field model of undrained soil shear strength is generated by using the Cholesky-Decomposition method. With the inclusion of a single layer of reinforcement, dimensionless bearing capacity factor, N always increases in both deterministic and probabilistic analysis. As the coefficient of variation of the undrained soil shear strength increases, the mean N value in both unreinforced and reinforced slopes reduces for particular values of correlation length in horizontal and vertical directions. For smaller correlation lengths, the mean N value of unreinforced and reinforced slopes is always lower than the deterministic solutions. However, with the increment in the correlation lengths, this difference reduces and at a higher correlation length, both the deterministic and probabilistic mean values become almost equal. Providing reinforcement under footing subjected to eccentric load is found to be an efficient solution. However, both the deterministic and probabilistic bearing capacity for unreinforced and reinforced slopes reduces with the consideration of loading eccentricity.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.14 no.2
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• pp.128-135
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• 2002

An existing numerical model fo r determining the wave field and pore pressures inside rubble mound breakwater was reformulated here especially to enhance the predictability of interior pore pressures. The pore pressures strongly depend on the nonlinear wave field occurring along frontal slope which is very difficult to be numerically reproduced. In the present study, hence, the amplitude and phase informations of wave pressures along the frontal slope are obtained directly through a hydraulic model test and are incorporated into the numerical model. The interior wave field is analyzed by a boundary element method, and thereby the pore pressures are determined. It was found that the calculated pore pressures agreed quite well with experimental values.

• The Journal of Engineering Geology
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• v.19 no.2
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• pp.191-203
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• 2009

The effect of stabilizing piles on cut slopes is checked and the behavior of slope soil and piles are observed throughout the year by field measurements on the large-scale cut slopes. First of all, the behavior of the slope soil was measured by inclinometers during slope modification. Landslides occurred in this area due to the soil cutting for slope modification. The horizontal deformations of slope soil are gradually increased and rapidly decreased at depth of sliding surface. As the result of measuring deformation, the depth of sliding surface below the ground surface can be known. Based on the measuring the depth of the sliding surface, some earth retention system including stabilizing piles were designed and constructed in this slope. To check the stability of the reinforced slope using stabilizing piles, an instrumentation system was installed. As the result of instrumentation, the maximum deflection of piles is measured at the pile head. It is noted that the piles deform like deflection on a cantilever beam. The maximum bending stress of piles is measured at the soil layer. The pile above the soil layer is subjected to lateral earth pressure due to driving force of the slope, while pile below soil layer is subjected to subgrade reaction against pile deflection. The deflection of piles is increased during cutting slope in front of piles for the construction of soil nailing. As a result of research, the effect and applicability of stabilizing piles in large-scale cut slopes could be confirmed sufficiently.

• Journal of the Korean Geosynthetics Society
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• v.16 no.4
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• pp.139-149
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• 2017

The maintenance, repair, and reinforcement projects and structural stability assessments of Seokguram have primarily focused on examining the condition of stone members of Seokguram and the concrete dome structure for Seokguram. However, a 12 m-high rock slope located behind Seokguram raises a concern of slope failure and rockfall, which may reduce stability of Seokguram. It is also unclear whether the soil slopes and masonry wall at the side and the front of Seokguram have sufficient long-term stability against localized heavy rains and earthquakes, which have been frequent in recent years. The present study investigates the ground and the slopes around Seokguram using detailed field survey to identify geographical and geological risk factors, and assess structural stability of the exposed rock mass behind and the slope in front of Seokguram and the masonry wall using stability analysis.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.3
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• pp.91-100
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• 2010

In this paper a sensitivity analysis about effects of influencing factors on the stability of soil cut and embankment slopes in field was performed. Slope stability analysis of slopes in field was carried out with dry, rainy and seismic conditions. As results of analyzing the sensitivity of factors for the dry and rainy conditions, effect of cohesion, internal friction angle and unit weight of soil on the stability of cut slope is more critical in the dry condition than in the rainy condition. However, their effects on the stability of embankment slope for both conditions are similar to each other. The horizontal seismic coefficient does also affect the stability within the similar range of values irrespective of dry or rainy conditions. Cohesion and internal friction angle are more dominant factors influencing the slope stability irrespective of dry or rainy conditions than unit weight of soil and the horizontal seismic coefficient.

• Journal of Korean Society on Water Environment
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• v.25 no.3
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• pp.441-451
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• 2009

To evaluate the soil erosion best management practices, many computer models has been utilized over the years. Among those, the USLE and SWAT models have been widely used. These models estimate the soil erosion from the field using empirically-based USLE/MULSE in it. However, these models are not good enough to estimate soil erosion from highland agricultural watershed where severe storm events are causing soil erosion and muddy water issues at the receiving watersheds. Thus, physically-based WEPP watershed version was applied to a watershed, located at Jawoon-ri, Gangwon with very detailed rainfall data, rather than daily rainfall data. Then it was validated with measured sediment data collected at the sediment settling ponds and through overland flow. In this study, very detailed rainfall data, crop management data, soil data reflecting soil reconditioned for higher crop production were used in the WEPP runs. The $R^2$ and the EI for runoff comparisons were 0.88 and 0.91, respectively. For sediment comparisons, the $R^2$ and the EI values were 0.95 and 0.91. Since the WEPP provides higher accuracies in predicting runoff and sediment yield from the study watershed, various slope scenarios (2%, 3%, 5.5%, 8%, 10%, 13%, 15%, 18%, 20%, 23%, 25%, 28%, 30%) were made and simulated sediment yield values were analyzed to develop appropriate soil erosion management practices. It was found that soil erosion increase linearly with increase in slope of the field in the watershed. However, the soil erosion increases dramatically with the slope of 20% or greater. Therefore special care should be taken for the agricultural field with slope greater than 20%. As shown in this study, the WEPP watershed version is suitable model to predict soil erosion where torrential rainfall events are causing significant amount of soil loss from the field and it can also be used to develop site-specific best management practices.

• Journal of the Korean Geosynthetics Society
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• v.12 no.4
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• pp.35-44
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• 2013

This paper presents the slope wall technique using soil improvement material for reinforced soil slope through laboratory scale model tests, and verifies the experimental results comparing with numerical analysis. In additional, case study in field has performed to investigate the deformation of reinforced soil slope for 6 months. As a result of laboratory scale model test, numerical analysis, and case study, the reinforcement effect of the slope wall technique using soil improvement material is sufficient to be constructed as reinforced soil slope. The technique shows the stable ratio (0.4%) of horizontal to vertical deformation in the surface loading.