• Structural Engineering and Mechanics
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• v.84 no.5
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• pp.591-604
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• 2022

A gravity wall combined with an anchoring lattice frame (a combined retaining structure) is adopted at a typical engineering site at Dali-Ruili Railway Line China. Where, the combined retaining structure supports a soil deposit covering on different inclined rock slopes. With an aim to investigate and compare the effects of inclined rock slopes on the response of combined retaining structure under seismic excitation, three groups of shaking table tests are conducted. The rock slopes are shaped as planar surfaces inclined at angles of 20°, 30°, and 40° with the horizontal, respectively. The shaking table tests are supplemented by dynamic numerical simulations. The results regarding the horizontal acceleration response, vertical acceleration response, permanent displacement mode, and axial anchor force are comparatively examined. The acceleration response is more susceptible to outer structural profile of combined retaining structure than to inclined angle of rock slope. The permanent displacement decreases when the inclined angle of the rock slope increases within a range of 20°-40°. A critical inclined angle of rock slope exists within a range of 20°-40°, and induces the largest axial anchor force in the combined retaining structure.

• Journal of the Korean earth science society
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• v.31 no.6
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• pp.555-562
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• 2010

Three-dimensional laser scanner was used to accurately measure any possible strain on a slope under pertaining stress with the time difference of 7 months. The laser scanner has the ability to measure the 3-D coordinate of a target point by calculating the travel time of laser beam between the laser device and the target point, and has been proved to be effective for analysis of the displacement of slopes or large construction. The scanning data measured with time difference were analyzed to find any strain by approaches of plane angle change, curvature variation, twist of frame, displacement of merging point, etc. From the analysis, some weak points showing heavily distorted shape were detected, which was used to design the reinforcement.

• Journal of the Korean Geosynthetics Society
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• v.16 no.3
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• pp.1-10
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• 2017

Recently, one of the natural disasters, landslide is causing huge damage to people and properties. In order to minimize the damage caused by continuous landslide, a scientific management system is needed for technologies related to measurement and monitoring system. This study aims to establish a management system for landslide damage by prediction of slope failure. Ground behavior was predicted by surface ground deformation in case of slope failure, and the change in ground displacement was observed as slope surface. As a result, during the slope failure, the ground deformation has the collapse section, the after collapse precursor section, the acceleration section and the burst acceleration section. In all cases, increase in displacement with time was observed as a slope failure, and it is very important event of measurement and maintenance of risky slope. In the future, it can be used as basic data of slope management standard through continuous research. And it can contribute to reduction of landslide damage and activation of measurement industry.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.651-658
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• 2004

In this study, we introduced the spiral pipe nailing system (refer as SPN system) with self drilling method, can apply to ground which is hard to keep shape of bore hole, and performed limit equilibrium analysis with simplilied trial wedge method while length ratio and bond ratio were altered to evaluate slope stability considered of tensile strength and bending stiffness. A newly soil nailing system named as the SPN system is respected to reduce displacement of nail and increase global slope stability. And effects of various factors related to the design of the SPN system, such as the type of drilling method and the bit, are examined throughout a series of the displacement-controlled field pull-out tests. 6 displacement-controlled field pull-out tests are performed in the present study and the volume of grouting arc also evaluated based on the measurements. In addition, short-term characteristics of pull-out deformations of the newly proposed SPN system are analyzed and compared with those of the general soil nailing system by carrying out the displacement-controlled field pull-out tests.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2007.04a
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• pp.409-412
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• 2007

To minimize damages caused by landslides due to severe rain falls and storms during the rainy season every year, it is necessary to carry out research to monitor the symptoms of landslide in advance and prevent them. If proper actions ate taken in advance by monitoring the symptoms of landslide, personal and property damages caused by landslides can be prevented or minimized. This study tries to measure the movement of model slopes after causing displacement to each model slope using no prism Total Station and examine the applicability of Total Station by displacement through the analysis of the data.

• Journal of the Korean Society of Safety
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• v.23 no.1
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• pp.28-34
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• 2008

The corrugated steel plate structures is applied to the construction of mountain tunnel portal part with shallow depth, the tunnel on the outskirts of urban areas and ecology move passage. In this study, A finite element method is used for research the behavior of corrugated steel plate structures due to construction position under declinating earth pressure and excavation depth. A finite element method were performed varying construction position(10, 15, 20 and 25m) from slope and excavation depth from surface. The hoop thrust and moment, displacement of corrugated steel plate subjected to construction position and excavation depth is determined from a finite element method. From results of finite element method, it was found that the increase of thrust and the decrease of displacement as the amount of distance increase from slope with construction position. But the thrust and moment, displacement has not different value with excavation depth.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.51-60
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• 2006

At new constructing national road, a cutting slope was surveyed and gotten face mapping for three months. The slope is composed of gray phyllite and coaly slate which is the Chang-ri Formation, Okcheon system. The slope angle is 40 degree and the direction is NNE. The attitude of schistosity is $260^{\circ}/45^{\circ}$. So the slope direction is nearly parallel to the schistosity. This is the reason that the slope is very unstable. On the other hand, the very unstable slope is caused by the direction of the schistosity and the slope. First month the coaly slate was slided through the schistosity plane about 10cm. However, three months late the displacement was 2m maximum.

• Journal of the Korean Geotechnical Society
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• v.39 no.7
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• pp.57-67
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• 2023

Slope failures during rainfall have been observed in mountainous areas of South Korea as a result of the presence of solar power facilities. The seepage behavior and pore pressure distribution differ from typical slopes due to the presence of impermeable solar panels, and the load imposed by the solar power structures also affects the slope behavior. This study aims to develop a method for evaluating the stability of slopes with solar power facilities and to analyze vulnerable points by considering the maximum slope displacement. To assess the slope stability and predict behavior while considering rainfall seepage, a combined seepage analysis and finite difference method numerical analysis were employed. For the selected site, various variables were assumed, including parameters related to the Soil Water Characteristic Curve, strength parameters that satisfy the Mohr-Coulomb failure criterion, soil properties, and topographic factors such as slope angle and bedrock depth. The factors with the most significant influence on the factor of safety (FOS) were identified. The presence of solar power facilities was found to affect the seepage distribution and FOS, resulting in a decreasing trend due to rainfall seepage. The maximum displacement points were concentrated near the upper (crest) and lower (toe) sections of the slope.

• Journal of the Korean Geotechnical Society
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• v.39 no.5
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• pp.27-40
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• 2023

A pile is a structural element that is used to transfer external loads from superstructures and has been widely utilized in construction fields all over the world. The method of installing a pile into the ground should be selected based on geotechnical conditions, location, site status, environmental factors, and construction costs, among others. It can be divided into two types: direct hammering and preboring. The direct hammering method installs a pile into the bearing layer, such as rock, using a few types of hammer, generating a considerable amount of pile driving-induced vibration. The vibration from pile driving influences adjacent structures and the ground; therefore, quantitatively investigating the effects of vibration is inevitably required. In this study, two-dimensional dynamic numerical modeling and analysis are performed using the finite difference method to investigate the influence on the adjacent slope, including temporary supporting system. Time-dependent loading induced by pile driving is estimated and used in the numerical analysis. Consequently, large surface displacement is estimated due to surface waves and less wave deflection, and refraction at the surface. The total displacement decreases with the increase of the distance from the source. However, lateral displacement at the top of the slope shows a larger value than vertical displacement, and the overall displacement tends to be concentrated near the face of the slope.

• Journal of the Korean Geotechnical Society
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• v.18 no.6
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• pp.5-16
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• 2002

A hydrogeomechanical numerical model is presented to evaluate rainfall impacts on groundwater flow in slopes and slope stability. This numerical model is developed based on the fully coupled poroelastic governing equations for groundwater flow in deforming variably saturated geologic media and the Galerkin finite element method. A series of numerical experiments using the model developed are then applied to an unsaturated slope under various rainfall rates. The numerical simulation results show that the overall hydromechanical slope stability deteriorates, and the potential failure nay initiate from the slope toe and propagate toward the slope crest as the rainfall rate increases. From the viewpoint of hydrogeology, the pressure head and hence the total hydraulic head increase as the rainfall rate increases. As a result, the groundwater table rises, the unsaturated zone reduces, the seepage face expands from the slope toe toward the slope crest, and the groundwater flow velocity increases along the seepage face. From the viewpoint of geomechanics, the horizontal displacement increases, and the vertical displacement decreases toward the slope toe as the rainfall rate increases. This may result from the buoyancy effect associated with the groundwater table rise as the rainfall rate increases. As a result, the overall deformation intensifies toward the slope toe, and the unstable zone, in which the factor of safety against shear failure is less than 1, becomes thicker near the slope toe and propagates from the slope toe toward the slope crest. The numerical simulation results also suggest that the potential tension failure is likely to occur within the slope between the potential shear failure surface and the ground surface.