• Korean Journal of Environment and Ecology
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• v.22 no.3
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• pp.268-279
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• 2008

This study is aimed at typifying the crossing structure and inquiring into the characteristics of vegetation distribution by type targeting Dorimcheon(stream), Banghakcheon(stream), Seongnaecheon(stream) and some sections of Yangjaecheon(stream) in Seoul through the establishment of basic data for restoring vegetation in urban stream. This research classified the crossing structure into 56 slope types and 31 vertical types in combination with the three items, such as bank slope(vertical style, slope style) of bank, absence or presence of waterside, and revetment structure. This research derived nine slope types including SB1 (revetment of low water level-revetment with vegetation, and revetment of high water level-nature riverside) including SG5(revetment of low water-concrete, and revetment of high water level-riprap work), and three vertical types, such as VH4(bank revetment-wet masonry), and VH7(bank revetment - concrete )from the target survey areas. Among these, both revetment of low water level and high water level were found to be distributed on the longest section as the type of SG7 and VG7 structured in concrete. As a result of inquiry and analysis of micro topography structure and vegetation structure of eight major types, this research could find out the influence of crossing structure on plant vegetation according to the characteristic by typified item, but there appeared no distinct characteristic of vegetation distribution by crossing structure.

• Journal of the Korean Geotechnical Society
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• v.24 no.12
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• pp.65-73
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• 2008

In the current practice for slope stability problem in Japan, the shear strength, $\tau$, mobilized along the failure surface is usually estimated based on an empirical approximation in which the cohesion, c, is assumed to be equal to the soil thickness above the supposed slip surface, d(m). This approximation is advantageous in that the result of stability analysis is not influenced by the designers in charge. However, since the methodology has little theoretical background, the cohesion may often be grossly overestimated, and conversely the angle of shear resistance, $\phi$, is significantly underestimated, when the soil thickness above the supposed slip surface is quite large. In this paper, a case record of natural slope failure that took place in Hyogo Prefecture in 2007, is described in detail for the case in which the shear strength along the collapsed surface was carefully examined in a series of direct shear box (DSB) tests by considering the effects of in-situ shear stress along the slip surface. It is demonstrated that the factor of safety agrees with that of in-situ conditions when the shear strength from this kind of DSB test was employed for the back-analysis of the slope failure.

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.4
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• pp.274-281
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• 2005

The climate of the Uisong Area is wet in the heat of summer and cold and dry in winter, The climate is highly consistent. The typical forest soil of the Uisong Area has an acidity of pH 4.5-5.6. The thickness of soil A layers is thin to an average of 10-20 cm and is a typical brown forest soil type. The growth characteristic of this climate and soil environment is as follows. In the case of Larix leptolepis, it takes 5-9 years to reach 6 cm diameter, The annual growth rate falls off greatly at an age of 17-19 years. The change of annual rings is more apparent on the north slopes compared with the east and northeast slopes. Pinus rigida takes 7-9 years to reach a 6 cm diameter. Annual growth rates of Pinus rigida fall greatly when age reaches 19 years. The change of annual ring growth of Pinus rigida was most apparent in the west and northeast slopes compared with the south and east slopes. In the case of Pinus koraiensis, the change of the annual ring width according to the characteristics of the slope is not important. Pinus koraiensis takes 6 yearsto reach the 6cm diameter, and annual growth rate fell off at age 19 years. In the case of Quercus acutissima, the growth of the valley trees is more stable than for trees grown at the mountain base. Annual growth rate of Quercus autissima fell off 19 years after planting. Ring growth of Robinia pseudo-acasia on northeast slopes appears much like that on northwest slopes. In conclusion, the main silviculture species reaches a 6 cm diameter in 5-9 years of growth, and the annual growth rate begins to fall between years 13 and 19 in the Uisong Area.

• The Journal of Engineering Geology
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• v.7 no.1
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• pp.53-62
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• 1997

Fracture mechanics properties of rock materials can he applied to predict the distribution of natural fractures in rock masses, and also to assess the safety of rock slopes and underground structures. In this study, rock fracture toughness and other fracture rrechanics properties of sorne lithologies showing apparently rock-property-controlled distribution of natural fractures were measured. Propagation behaviors of natural and experirnental fractures were also characterized both qualitatively and quantitatively, in terns of the propagation types and sorne statistical parameters. It was concluded that the application of fracture mechanics theories to the ge6logic materials should be based on the geological background and evidences.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.172-176
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• 2011

최근 들어 생활수준의 향상과 친수 환경에 대한 인식이 높아지면서 하천환경의 보전과 개선에 대한 필요성이 증대되고 과거 이수 또는 치수 목저으로 정비되었던 하천을 자연형 하천으로 탈바꿈 시키려는 움직임이 많이 일어 나고 있다. 자연형 하천 공법의 연구는 1990년대부터 점차 이루어 지고 있으나, 호안의 식생 공법 연구 및 수리 실험을 이루어 지지 않는 실정이다. 이제 본 연구에서는 자연형 하천 정비의 대표적인 방법인 호안 사면 처리 공법 중 지오셀 식생 매트에 대한 수리모형 실험을 실시하였다. 고정상 실험을 통하여 활착된 지오셀 식생 매트가 허용할 수 있는 유속과 수위를 정하는데 목적을 두었고, 상사법칙 이론을 도입하여 수행된 실험결과를 정리 분석하였다. 분석된 실험치를 왜곡모형에 적용하여 실제 규모로 환산한 결과 현재 설계시 허용되는 유속에도 지오셀 식생 매트의 안정성이 확보되는 것을 확인할 수 있었다. 따라서 호안의 지오셀 식생매트의 적용이 가능 할 것으로 보이나, 제한적인 실험결과에 의해 왜곡모형을 이용하여 현장조건을 추정한 것이므로 적용 및 해석에 있어서는 실제 설치되는 하천의 복잡한 수리 수문학적인 변수가 충분히 고려되어야 할 것이다.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1038-1049
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• 2008

The purpose of this case study is corrosive fall in Upper-Slope. Upper-slope of this slope affect in fall of the cut-slope because of wide valley. Deposit which is piled up naturally is the sinkage occurs gradually in upper-slope.

• 열린충남
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• s.67
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• pp.82-89
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• 2014

충남 계룡시 엄사면 광석리에는 '계룡 쌈채피망청정마을'이 자리잡고 있다. 일명 '광석마을'이라고도 불리는데, 마을 이름이 뭔가 호기심도 불러일으키면서 색다른 느낌이 들었다. 알고 보니 계룡시에서 하나밖에 없는 정보화마을 이라고 한다. 이번 여름호에서는 지난 5월말에 이 정보화마을을 운영하고 있는 문향심 팀장을 직접 찾아가 나눈 인터뷰 내용을 싣고자 한다. 정보화마을을 현주소와 방향, 그리고 마을의 가치를 조금이나마 되새겨 볼 수 있는 자리였다. 그런데 왜 위원장이 아니고 팀장이냐구요? 그것이 글을 끝까지 읽게되면 자연스럽게 알게 될 것이다.

• Journal of the Speleological Society of Korea
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• v.34 no.35
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• pp.67-77
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• 1993

제주도는 한반도의 남서 해안에 따로 떨어겨 있는 화산섬으로 동경 126$^{\circ}$09'44"~120$^{\circ}$57'00", 북위 33$^{\circ}$11'28"~33$^{\circ}$33'45"에 위치하며 N70E 장축을 가지는 동서 약 73km, 남북 약 32km의 타원형을 이루며 중앙에 한라산 1,950m를 중심으로 단추형의 화산섬을 이룬다. 장축인 동서방향은 매우 완만한 사면 3~5$^{\circ}$를 이루고 단축인 남북방향은 약간 급한 경사 5~7$^{\circ}$를 갖는 Aspite형 화산이다. 이것은 화산 분출이 전반기에는 강력한 분출이었으나 추기에 백록담을 화구로 한 중심 분출에 기인된 것이다.(중략)

• The Journal of Engineering Geology
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• v.17 no.3
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• pp.359-365
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• 2007

Freezing and thawing cycle is one of the major weathering-induced factors in the mechanical weathering of the rock mass. This natural process accelerates rock weathering process by breaking down the parent rock materials and makes soil or weathered rock formation in a rock slope surface zone. It can also cause reduction of the shear strength in slopes. It is important to calculate the deterioration depth caused by freezing-thawing for a slope stability analysis. In this study, deterioration depths of rock slope due to freezing-thawing were calculated using the 1-D heat conductivity equation. The temperature distribution analysis was also carried out using collected temperature distribution data for last five years of several major cities in Korea. The analysis was performed based on the distributed rock types in study areas. Thermal conductivities, specific heats and densities of the calculation rocks are tested in the laboratory. They are thermal properties of rocks as input parameters for calculating deterioration depths. Finally, the paper is showing the calculated deterioration depths of each rock type slopes in several major cities of Korea.

• Journal of Conservation Science
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• v.37 no.5
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• pp.505-515
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• 2021

In this study, we evaluated the slope stability of the Pohang Daljeon-ri columnar joint (Natural Monuments # 415) and calculated the maximum energy, jumping height and moving distance of rockfalls using a simulation. Based on the results, we established the range of rockfall risk. The slopes of the Pohang Daljeon-ri columnar joint have dip directions of 93.79°, 131.99°, 165.54° and 259.84° from left (SW) to right (NE). Furthermore, they have a fan-like shape. The Pohang Daljeon-ri columnar joints are divided into four sections depending on the dip direction. The measurement results of the discontinuous face show that zone 1 is 125, zone 2 is 261, zone 3 is 262, zone 4 is 43. The results of slope stability analyses for each section using a stereographic projection method correspond to the range of planar and toppling failure. Although it is difficult to diagnose the type of failure, risk evaluation of currently falling rocks requires further focus. The maximum movement distance of a rockfall in the simulation was approximately 66 m and the rockfall risk range was the entire area under slope. In addition, it is difficult to forecast where a rock will fall as it rolls in various directions due to topographic factors. Thus, the installation of measures to prevent falling is suggested to secure the stability based on the results of the rockfall simulations and its probabilistic analysis.