• 지질공학
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• 제10권2호
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• pp.18-35
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• 2000

우리나라에서 가장 흔히 발생하는 산사태는 쇄설성유동(debris flow)이며 이는 집중호우 시기인 6월-8월 사이에 대부분 발생한다. 조사통계에 의하면 2일간의 강우량이 200mm 이상일 때 발생하기 시작한다. 이들은 산사면의 노두 발달이 양호한 지역에서는 발생하지 않으면 노두가 없는 지역에서만 발생한다. 초기에는 전이형슬라이드(translational slide)로 시작되며 파괴물질이 산사면의 계곡으로 유동되면서 쇄설성유동으로 전이된다. 쇄설성유동의 원인이 되고있는 전이형 슬라이드의 발생인자는 강우와 인위적 조건을 제외하면 암석의 종류, 지형고도, 사면경사, 입도분표, 투수계수, 건조밀도, 공극율 등이다. 이들 발생인자들의 통계처리, 특히 로지스틱 회귀분석에 의하여 인자들의 정량적 가중치를 구하여 산사태 발생 확률을 정량화 하였다. 암반포행(rock mass creep)은 대부분 경상계 퇴적암지역에서 발생되면 직접원인은 거의 사면 하단 부의 절토 때문이다. 전단전이는 적은 편으로 1m 내외이나 포행암반의 규모가 크기 때문에 매우 위험하다. 칠곡, 부산 황룡산 터널입구, 사천 산사태 등이 이 범주에 속한다. 포행의 원인이 되는 상부 전단대는 대부분 주변에 발달되어있는 단층이나 대규모 전달절리와 연과되어 있어 사면설계 조사시 지질구조에 주의를 요한다. 회전형 슬라이드(rotational slide)는 토양층이 두껍거나 기반암이 심히 풍화된 연약층에서 발생하여 이들도 흔히 사면 하단부의 절토와 연관되어있다. 이 산사태는 원호 또는 반원호형으？ 진행되는 특징이 있으며 우리나라에서는 제 3기 응회암 지역이 취약하다. 이는 화산재와 화산쇄설 물질이 흔재된 제3기 응회암의 절리가 매우 잘 발달되어있어 팽윤과 흡수율이 높고 이로 인하여 심부까지 풍화에 취약하기 때문으로 경주 산사태와 포함-구릉포간 국도면의 산사태가 이 종류의 산사태에 속한다.

• Journal of Ecology and Environment
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• 제30권4호
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• pp.293-305
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• 2007

This study examined the distribution, population and vegetation structure of Corylopsis coreana in South Korea. C. coreana is distributed around the Suncheon area, Jeollanam-do, on the southern part of the Korean Peninsula, but the species is also found in Pocheon and Gangneung, on the central and central east parts of the peninsula. This discontinuous pattern of distribution is coupled with the unusual feature of only growing on northern exposed slopes. The mean density of C. coreana populations is 35 individuals per 100 $m^2$, ranging up to a maximum of 92 individuals per 100 $m^2$. Cut specimens sprouted a maximum of 38 stems per plant. Based on DCA analysis, the species' habitats was divided into three types by species composition and stratification structure. These types include: habitats affected strongly by human activities, valley and mantle communities which are affected relatively little by human activities, and stable forests. Populations affected by artificial intervention have actually flourished, while some populations in the stable forest system have declined. We conclude that the species, now endangered, should be maintained by means of specific external interventions such as cutting or removal of the canopy. To this end, further ecological data should be collected through monitoring and research to identify appropriate interventions to support threatened C. coreana populations.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2003년도 봄 학술발표회 논문집
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• pp.529-536
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• 2003

In domestic case occurrence of cut slopes according to construction and expansion of road is necessary more than 70% of country has been consisted of mountain area. In the case of Kang-won Do, there are much mountains locals in road wiping away a disgrace and expanded and slant is connoting collapse danger of incision side by each kind calamity being urgent. When route alteration enforces disadvantageous road extension, stability examination and processing way about large slope happened are serious. During road extension work in the Kang-won DO secure stability for falling rock of road slope and failure that happen and established suitable reinforcement and countermeasure in reply in necessity. The Slope is divided rock slope and soil slope, and then in order to analysis soil slope apply LEM theory. And rock slope examined stability about stereographic projection and wedge failure. Is going to utilize in reinforcement and failure prevention if it is efficient cutting as reinterpreting stability and secure stability and wish to consider effective and robust processing plan of great principle earth and sand side, and present countermeasure inside with these data hereafter applying suitable reinforcement countermeasure about unstable section.

• 한국환경복원기술학회지
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• 제8권3호
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• pp.13-20
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• 2005

This study was conducted to suggest the ecological restoration methods of the decomposed granite cut-slope by organic soil amendment materials. Field test carried out for the cut-slope with organic soil amendment materials method and other three revegetation methods in Cheongwon. Test revegetation plants were Festuca arundinacea, Lolium perenne, Dactylis glomerata, Lespedeza cyrtobotrya, and Arundinella hirta. The result of this study can be summarized as follows; 1. The soil hardness, the soil acidity, and the soil humidity of organic soil amendment materials method were at a suitable value for plants growth. And it was better as compared with other three revegetation methods of cutting-rock slopes. 2. The result of toxic substance investigation, all items were at a suitable for standard law. 3. During one year after seeding, most plants germinated and especially Festuca arundinacea and Dactylis glomerata grows well. Seedling numbers were 336.7 per $m^2$(after 6 months), 183.3 per $m^2$(after 10 months), and 353.3 per $m^2$(after 6 months). Ten months later after seeding, plants showed 80% ground coverage. Visual rate, plant height, and growth rate were excellence, Also, high plant growth in spring better than autumn.

• 한국기계가공학회지
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• 제15권4호
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• pp.8-15
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• 2016

Most machines lose a lot of energy due to friction. Wear due to friction also reduces performance. Therefore, it is important to reduce friction on the surface to improve energy efficiency and decrease wear. Surface texturing refers to making patterns on the surface for reducing friction. There are many surface texturing methods, such as using lasers, abrasive jet machining, and so on. Recently, mechanical manufacturing methods, such as cutting and grinding, have been highlighted. Among them, the grinding method has the advantage of making patterns in large areas quickly. Therefore, it is appropriate for surface texturing on large machines. This paper is a study on the slope change of the surface texturing pattern using grinding. Therefore, we researched the slopes of the patterns corresponding to "spindle speed and feed rate" and "curvature of workpiece surface" using a mathematical model and experiment. As a result, we made a proper mathematical model concerning our research. Therefore, using the mathematical model in this paper, we could predict the slope change of the pattern according to grinding conditions.

• 한국농공학회지
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• 제23권1호
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• pp.86-102
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• 1981

The soil test data of 28 earth dams, scheduled to be constructed in Kore3, were selected for this study. The safety factors of their side slops were computed using Fellenius' "slice Method" by computer. The results summarized in this study are as follows; 1. Dam sections can be easily determined by fig.10 without a time consuming trial and error calculations of assumed sections. 2. For the economical design of earth dam sections, it was found that more cohesive soil was suitable for lower dams(dam height less than 25m) and soils with a higher friction angle was better for higher dams 3. In the case that used soil materials have the same Internal friction angle, side slope increase was almost same. 4. The relationship between side slope and friction angle was found as log.S=a tan ø+b (Fig. 7) 5. The relationship between side slope and cohesion (c) was also found as log. S=a c+b (Fig. 8) 6. The change of safety factors due to the change of central core materials was very little (Table-2) 7. The decrease of safety factors according to the unit weight increase of embankment materials was negligible. 8. In general the relationship between the wet unit weight and the saturated unit weight was r sat = (rt)$^2$+0. 140. This study will contribute to the determination of economic and safe planning and designing of earth dams, embankments and cutting side slopes.

• 한국조경학회지
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• 제20권3호
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• pp.33-43
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• 1992

The perceptual characteristic on the slope scenery around highway is very similar as the general perceptual characteristic in the landscape. This process determines by the relationship between the scenery observers and the characteristics of its place. It is very important to have a analysis on highway slope scenery in our particular culture in Korea since our country's highways are done by cutting mountains : therefore, we have a lot of slopes around highways. The physical characteristics on the highway scenery determines how we should build scenery around highway to a satisfactory level. The results drawn from this research work are as follow: 1) The satisfaction for slope scene had been affected by sex, native and experience of travel. I thought that the slope scene having peculiar form will offer the highest satisfaction. 2) Psychological factor, reflected satisfaction of slope scene, 몽 a grip of three factors as the factor of evaluation, texture, formation, and presumption formula is : Satisfaction=1.04(Evauluation factor)+0.83(Texture factor)+0.15(Formation factor)+4.28)R2=0.69). 3) Vine among the vegetation componeents of slope scene highly correlated with the evaluation factor and grass, shrub correlated with the texture factor. 4) Rock among the structual components of slope scene highly correlated with the formation factor, and stockade, lattice correlated with the evalution factor. 5) Gradient among the properties which determined slope form, highly correlated with the formation factor.

• 한국환경복원기술학회지
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• 제1권1호
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• pp.95-101
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• 1998

In order to seek a efficiency of site cooperation and slope stabilization in a rock sloping work, it would rather take into consideration, in its importance, a concurrent performance of civil works and landscaping works than give any part a special priority. It can enable us to achieve an expanded scope of landscaping works and improvement of slope scenery via this sort of cooperation. However, this can not be achieved without assurance on the slope stabilization and scenic view of the project owner, and further via this cooperation, environmentally familiar works can be performed, becoming natural environment and minimizing damages on surrounding scenery and environment. It is foreseeable that improvement of functions of civil equipment, introduction of technology and development of landscaping materials can facilitate an improvement in the betterment of slope scenery. Landscaping related parties need to enhance their understanding of rock sloping and scenic view based on knowledge on the fundermental understanding of slope stabilization and on the base rock characteristics.

• 지질공학
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• 제12권2호
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• pp.137-150
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• 2002

최근 경상분지 퇴적암 지대에서 절개사면 형성 시, 20$^{\circ}$ 저각 경사의 층리면을 따른 평면파괴 양상이 빈번하게 발생하고 있다. 부산시에서 1999년 발생한 황령산 산사태도 이 범부에 속한다. 현재 황령산사면은 사면구배가 1:2.0으로 재조정 되어 2000년도에 공사가 마무리되었다. 황령산 산사태의 사면파괴형태에 대한 분석을 하기위하여 현장 암반조사 및 시험, 시추, 실내 시험, 항공사진판독, X-선 회절분석, 평사투영법 및 한계평형법을 이용한 사면 안정성 분석등이 실시되었다. 그 결과, 산사태 발생 1년 전부터 인장균열들이 연장 발달하는 것이 확인 되었고, 인장균열은 여러방향의 절리들이 합쳐저 생성된 것으로 생각된다. 파괴암체도 각각 다른 층리면을 따라 붕괴된 것으로 분석되었다. 평사투영법 및 한계평형법을 이용한 안정성 검토결과 활동면으로 작용한 녹회색 응회질 셰일층이 풍화된 경우 평면파괴의 위험성이 있는 것이 확인되었다. 향후 이와 유사한 지역에서 절개사면 건설 시, 박층의 풍화에 약한 층에 대한 세밀한 조사가 필요하며 이에 대한 안정성 분석이 수행되어야 한다.

• 한국지반환경공학회 논문집
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• 제9권4호
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• pp.23-36
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• 2008

쏘일네일링 공법은 수동보강재를 이용하여 원지반의 전단강도를 증가시켜 지반을 보강하는 공법이다. 쏘일네일링 공법에서 전면벽체는 현장타설 콘크리트 격자블록과 현장타설 콘크리트 벽체의 2가지 형태가 있으며, 1:0.7 보다 완만한 사면일 경우에는 현장타설 콘크리트 격자블록이 사용되고 있다. 또한 1:0.5 보다 급한 사면인 경우에는 숏크리트에 두께 30cm 정도의 현장타설 콘크리트 벽체를 합벽으로 시공하는 형태의 전면벽체가 활용되고 있다. 이 연구는 새로운 쏘일네일링 공법으로 조립식 쏘일네일링 공법을 제안하였다. 조립식 쏘일네일링 공법은 두께 20cm의 공장 제작된 콘크리트 패널을 사용하여 조립식으로 시공하는 공법으로 기존의 쏘일네일링 공법에 비해 전면벽체의 품질과 시공성을 향상시킬 수 있으며, 사면 절취 후 바로 콘크리트 패널을 절취면에 부착하여 전체 사면의 안정성을 증대시키는 효과가 있다. 본 연구에서는 실물규모의 사면단면에 파괴재하시험을 실시하여 조립식 쏘일네일링 공법에서 사용하고 있는 콘크리트 패널에 의한 전면벽체의 강성에 의한 구속효과에 의한 영향을 규명하고자 하였다. 대형파괴재하시험결과 숏크리트 전면벽체로 시공된 일반 쏘일네일링 공법에 비해 콘크리트 패널의 강성 전면벽체를 사용한 조립식 쏘일네일링 공법의 경우 하중-침하 관계가 우수한 것으로 나타났다.