• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.14 no.3
• /
• pp.583-594
• /
• 1994

One of the major elements of a natural landslide is the increase of the pore water pressure in a weakened layer. Therefore, the measurement of the pore water pressure in the layer is important. This work is a laboratory model study of the measurement of the pore water pressure with regard to the confined groundwater level, the permeability of the crack zone and the weathering degree of the weakened layer. By the model of the Tertiary period failure type and the Colluvium failure type, the reactions of the pore air pressure and the pore water pressure were measured in the weakened layer according to the permeability of the filter on the condition of the confined groundwater states. On the reaction phase of the pore pressure according to the during time, the Tertiary period failure type proved to be a step type and the Colluvium failure type turned out to be a wave type. The reaction ratios of the pore water pressure in the Tertiary period failure type are higher than the Colluvium failure type, decrease according to increasing of the weathering degree of the weakened layer.

• The Journal of Engineering Geology
• /
• v.20 no.4
• /
• pp.437-447
• /
• 2010

A probabilistic analysis of slope stability is an appropriate solution in dealing with uncertainty in problems related to engineering geology. In this study, a Monte Carlo simulation was performed to evaluate the performance function that is Barton's equation. A large number of randomly generated values were obtained for random variables, and the performance function was calculated repeatedly using randomly generated values. A previous study provided information of slope geometry and the random characteristics of random variables such as JRC and JCS. The present approach was adopted to analyze two failed slopes. The probabilities of failure were evaluated for each slope, and sensitivity analysis was performed to assess the influence of each random variable on the probability of failure. The analysis results were then compared with the results of a deterministic analysis, indicating that the probabilistic analysis yielded reliable results.

• Proceedings of the KGS Conference
• /
• 2004.05a
• /
• pp.43-43
• /
• 2004

본 연구지역은 강원도 강릉시 사천면 노동리에 위치해 있다. 이 지역에서는 2000년 4월에 산불이 발생한 지역으로 사면에 목본이 거의 없고 초본이나 조립사업에 의해 작은 나무들이 식재 되어 있다. 연구지역 일대의 지질은 쥬라기 대보 화강암인 흑운모화강암으로 이루어져있다. 화강암으로 이루어진 본 연구지역에서는 토어(tor), 핵석(core stone) 등을 일부 확인할 수 있으며 유수의 침식을 많이 받은 능선이나 계곡을 따라 기반암이 노출되어 있다. (중략)

• The Journal of Engineering Geology
• /
• v.17 no.4
• /
• pp.545-554
• /
• 2007

Landslides is mainly induced by a heavy rainfall, earthquake ground motion, and some other factors like soil mechanics, morphological-geological factors etc. Since the starting point of the failure seemed to be originated at a construction site in the study, it is meaningful to find out the relationship between the landslide and the construction. For this study, the slope failure factor was examined carefully to see that the original natural slope had vulnerability and that the complex ground had unstability changed by construction. A field survey was conducted on the original ground surface and filled-up ground. A laboratory test was also conducted to determine the geomechanical properties of soil samples. 2D and 3D limit equilibrium analysis with changing groundwater level were conducted at the failure depth using a seismic refraction survey. The result shows that the factor of safety is similar stability under all condition, but unstable under saturated condition.

• Ecology and Resilient Infrastructure
• /
• v.6 no.4
• /
• pp.258-266
• /
• 2019

This study was conducted to apply natural river technologies to levees and examine the results. The new eco-friendly bio-polymer was applied, a combination of eco-friendly biopolymers and soil, to levee slope to enhance durability and eco-friendliness and to establish reinforcement measures against unstable levees due to overtopping. A semi-prototype levee of 1 m in height, 3 m in width, with a 1:2 slope and 5 m length, was constructed at the Andong River Experiment Center. The bio-soil mixed with the biopolymer and the soil at an appropriate ratio was treated with a 5 cm thickness on the surface of levee to perform the stability evaluation according to overtopping. Using the pixel-based analysis technique using the image analysis program, the breached area of levee slope was calculated over time. As a result, the time for complete decay occurs more than 12 times than that of ordinary soil levee. Therefore, when the new substance is applied to the surface of levee, the decay delay effect appears to be high.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.33 no.4
• /
• pp.1377-1387
• /
• 2013

Most embankment of the reservoirs (99.1 %) have been constructed in the earth filled type in Korea because the construction of this type is less expensive and simpler than others such as concrete one. However, it has to be reinforced the slope to prevent the breach due to overtopping or piping under unexpected flood conditions. This study has been analyzed the retardation effect using three types (L, T, $L^*$ shape) of stiffener in order to reinforce embankment when they are collapsed by overtopping flow. Experimental results showed that L-type stiffener is the most effective in delaying the breaching of embankment and reducing the soil erosion when compared with others. The reinforced embankment breaching showed that time delay was occurred about 1.73 to 2.29 times and the peak flowrate was reduced compared to non-stiffener embankments due to energy dissipation by collision and less soil erosion. The embankment breaching mostly leads to major damages because of the lack of repair time. Thus, since these stiffeners can resist the rapid breach, it would be possible to earn the time to emergency repair and lifesaving, as well as reduction of damages of embankment in downward region with decreasing peak flowrate. Results from this study would be used for the basis when establishing the emergency action plan for the reservoirs on the verge of hazard.

• Proceedings of the Korean Geotechical Society Conference
• /
• 1995.06a
• /
• pp.157-175
• /
• 1995

• 지반과기술
• /
• v.3 no.2
• /
• pp.44-53
• /
• 2006

• Disaster Prevention Review
• /
• v.14 no.3
• /
• pp.110-111
• /
• 2012

• Geotechnical Engineering
• /
• v.29 no.1
• /
• pp.19-23
• /
• 2013