• 한국지하수토양환경학회지:지하수토양환경
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• 제22권6호
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• pp.85-93
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• 2017

In this study, the concepts of soil degradation, soil pollution and soil damage are defined, and the domestic and foreign administrative systems related to soil pollution and soil damage management are analyzed. In case of foreign countries, laws and regulations on the soil conservation and soil damage management were analyzed. In case of Korea, the present state of the legal system governing soil pollution and damage management was analyzed in each aspect. Through this study, suggestions for amendments of relevant laws were proposed by establishing policy direction for integrated management of soil pollution and soil damage. The results of this study will provide a basis for integrated management of soil pollution and damage, and it can be utilized in establishing integrated management strategy of long term soil conservation and sustaninable soil development at national level.

• Earthquakes and Structures
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• 제7권3호
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• pp.349-365
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• 2014

The dynamic response of structures under extremely short duration dynamic loads is of great concern nowadays. This paper investigates structures' response as well as the associated structural damage to explosive loads considering and ignoring the supporting soil flexibility effect. In the analysis, buildings are modeled by two alternate approaches namely, (1) building with fixed supports, (2) building with supports accounting for soil-flexibility. A lumped parameter model with spring-dashpot elements is incorporated at the base of the building model to simulate the horizontal and rotational movements of supporting soil. The soil flexibility for various shear wave velocities has been considered in the investigation. In addition, the influence of variation of lateral natural periods of building models on the obtained response and peak response time-histories besides damage indices has also been investigated under blast loads with different peak over static pressures. The Dynamic response is obtained by solving the governing equations of motion of the considered building model using a developed Matlab code based on the finite element toolbox CALFEM. The predicted results expressed in time-domain by the building model incorporating SSI effect are compared with the corresponding model results ignoring soil flexibility effect. The results show that the effect of surrounding soil medium leads to significant changes in the obtained dynamic response of the considered systems and hence cannot be simply ignored in damage assessment and response time-histories of structures where it increases response and amplifies damage of structures subjected to blast loads. Moreover, the numerical results provide an understanding of level of damage of structure through the computed damage indices.

• 한국환경복원기술학회지
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• 제18권6호
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• pp.97-110
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• 2015

This study aimed to classify damaged lands, to find what are the damage factors affecting the studied area, and to present a prescription in order to provide some benefit for the restoration of Regional Ecological Network at Chungnam province. Finally we classified damaged lands from 1st to 4th damaged lands according to relative intensity of damage. The main damage factors for the First Damage Lands were humus horizon, soil hardness and plant species richness. In the Second Damage Lands, those were soil hardness, plant species richness, number of plants and dominant plant species. In the Third Damage Lands, those were humus horizon, soil hardness, plant species richness, number of plants and dominant plant species. In the Fourth Damage Lands, those were humus horizon, organic matter, soil hardness, EC, T-N content, plant species richness, number of plants and dominant plant species. In every cases, the damage of soil and vegetation was originated due to development carried out by human being. The changes in soil condition were not big enough for it to affect plant growth, however, degradation of vegetation was still severe.

• 한국지하수토양환경학회지:지하수토양환경
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• 제28권5호
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• pp.68-77
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• 2023

The effect of soil damage on the physicochemical characteristics and activity of the soil microbial community is not well known. This study investigates this relationship by analyzing 11 soil samples collected from various points of soil damage across Gyeonggi-do. Soil damage resulted from forest fires, landslides, and development areas, with their impacts most severe on the topsoil layer (0-30 cm). Dehydrogenase and β-glucosidase activities were notably higher at locations damaged by forest fires compared to other sites. While enzyme activities in soils influenced by landslides and development areas were relatively low, sites with a pollution history exhibited elevated dehydrogenase activity, likely due to past microbial response to the pollution. Additionally, an assessment of carbon substrate usability by soil microorganisms indicated higher substrate availability in areas impacted by forest fires, contrasting with lower availability in landslide and development sites. Statistical analysis revealed a positive correlation between organic content of sand and clay and microbial activity. These findings provide valuable insights into soil damage and associated restoration research, as well as management strategies.

• Geomechanics and Engineering
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• 제11권3호
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• pp.421-438
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• 2016

Explosions inside transportation tunnels might result in failure of tunnel structures. This study investigated the failure mechanisms of circular cast-iron tunnels in saturated soil subjected to medium internal blast loading. This issue is crucial to tunnel safety as many transportation tunnels run through saturated soils. At the same time blast loading on saturated soils may induce residual excess pore pressure, which may result in soil liquefaction. A series of numerical simulations were carried out using Finite Element program LS-DYNA. The effect of soil liquefaction was simulated by the Federal Highway soil model. It was found that the failure modes of tunnel lining were differed with different levels of blast loading. The damage and failure of the tunnel lining was progressive in nature and they occurred mainly during lining vibration when the main event of blast loading was over. Soil liquefaction may lead to more severe failure of tunnel lining. Soil deformation and soil liquefaction were determined by the coupling effects of lining damage, lining vibration, and blast loading. The damage of tunnel lining was a result of internal blast loading as well as dynamic interaction between tunnel lining and saturated soil, and stress concentration induced by a ventilation shaft connected to the tunnel might result in more severe lining damage.

• 건축역사연구
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• 제22권6호
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• pp.47-58
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• 2013

The purpose of this study is to analyze the cause of damage to the three storied stone pagoda of Bulguksa temple in GyeongJu. This report is attempted to making reinforcement and conservation plan through investigating and analyzing the cause of damage to that. The damage is caused by occurring of stress, degrading of stone strength, changing of underground soil structure, natural disasters and so on. Compressive stress, shear stress, bending stress and lateral pressure affected to the pagoda since built up. Ultrasonic examination data tells the strength of the stone. According to this result, strength of the stereobate stone materials is enough to support the weight of the upper ones. But we could found many other factors of the damage could consider, for example the problems occurred on building the pagoda construction and the weakness of the stone material(soft rock). And many environmental factors being changed in soil structure(subsidence of soil and degradation of bearing power of soil and freezing and melting of soil) can be seen as the cause of the damage. Natural disasters like earthquake, lightning and heavy rain were also thought to give direct impact to the damage. At last Concentration of compressive stress caused the crack and exfoliation on the stone materials and shear stress, bending stress and lateral pressure were main causes of the stereobate stone materials shearing.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회 3차
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• pp.86-95
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• 2010

Ground movements during tunnelling have the potential for major impact on nearby buildings, utilities and streets. The impacts on buildings are assessed by linking the magnitude of ground loss at the source of ground loss around tunnel to the lateral and vertical displacements on the ground surface, and then to the lateral strain and angular distortion, and resulting damage in the building. To prevent or mitigate the impacts on nearby buildings, it is important to understand the whole mechanism from tunnelling to building damage. This paper discusses tunneling-induced ground movements and their impacts on nearby buildings, including the importance of the soil-structure interactions. In addition, a building damage criterion, which is based on the state of strain, is presented and discussed in detail and the overall damage assessment procedure is provided for the estimation of tunnelling-induced building damage considering the effect of soil-structure interaction.

• 한국자원식물학회지
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• 제23권2호
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• pp.172-178
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• 2010

천연집단에 서식하는 개비자나무 개체들을 이용해 무생물 및 생물적 환경인자가homoharringtonine(HHT) 함량에 미치는 영향을 조사하여 향후 항암제 가능성이 있는 HHT의 고부가가치 산업적인 생산이 기대되는 연구에 기초자료를 제공하고자 본 연구를 수행하였다. 무생물적 환경인자(토양습도, 토양pH, 서식밀도, 기온)와 HHT 함량과의 상관관계에 있어 HHT 는 토양습도(0.77)와 토양pH(-0.68)에서 높은 상관을 보였다. 고도에 따른 무생물적 환경인자 (토양습도, 토양pH)와 HHT 의 함량 관계에 관해 다중회귀 분석을 실시한 결과, 토양 습도의 회귀계수($26.48^{***}$) 만 유의하여 토양 습도가 상대적으로 HHT 함량에 높은 영향을 미치는 것으로 나타났다. 생물적 환경인자(damage index)에 따른 HHT 함량에 미치는 영향을 살펴 본 결과, HHT는 2차곡선회귀적으로 증가하다 감소하는($H=278.23+1242D-398.87D^2$) 경향을 보였고 damage index는 HHT 함량에 높은 영향을 미치는 것으로 분석되었다. 마지막으로 HHT 의 함량에 영향을 미치는 최적환경인자를 분석한 결과, damage index와 토양 습도 모두가 2차다항회귀식으로 가장 적합하였고 결정계수는 각각 0.73와 0.67로 damage index가 상대적으로 HHT 함량에 높은 영향을 미치는 것으로 나타났다. 이는 섭식자 또는 균류와 같은 스트레스로 인한 방어기작이 HHT 의 생성에 높은 영향을 미치는 것으로 판단된다.

• Earthquakes and Structures
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• 제15권3호
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• pp.307-317
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• 2018

The current study explores the soil-structure interaction (SSI) effect on the potential seismic damage of mid-rise non-seismically designed reinforced concrete frames retrofitted by Fibre Reinforced Polymer (FRP). An 8-storey reinforced concrete frame poorly-confined due to transverse reinforcement deficiency is selected and then retrofitted by FRP wraps to provide external confinement. The poorly-confined and FRP retrofitted frames with/without SSI are modelled using hysteretic nonlinear elements. Inelastic time history and damage analyses are performed for these frames subjected to different seismic intensities. The results show that the FRP confinement significantly reduces one or two damage levels for the poorly-confined frame. More importantly, the SSI effect is found to increase the potential seismic damage of the retrofitted frame, reducing the effectiveness of FRP retrofitting. This finding, which is contrary to the conventionally beneficial concept of SSI governing for decades in structural and earthquake engineering, is worth taking into account in designing and evaluating retrofitted structures.

• 한국작물학회지
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• 제14권
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• pp.147-157
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• 1973

I. 보리 발아시 과습조건이 될 때 그 발아에 미치는 영향을 알고져 건토(LiC) 100g당 30cc, 40cc, 50cc, 60cc의 비율로 물을 가하여 수분함량을 각각 다르게 한 조건을 만들어 Check에 대비하여 Machete(Butachlor), TOK(Nitrofen)을 각각 150g, ai/10a 비율로 처리하였던바 그 결과를 요약하면 다음과 같다. 1. 보리 발아시 수분함량이 포장용수량 이상의 과습이 유지될 때는 무처리구에 있어서도 발아율이 급감하거나 발아되지 아니하며 일단 발아된 후에도 근신장 및 생육이 제대로 되지 못하였다. 2. Machete, TOK 등 약제처리구에 있어서도 1)과 경향은 같으나 무처리구 보다는 그 해가 더욱 증대되였다. II. 토성이 다른 4종류의 토양을 대상으로 하여 Machete (제형별 180 g ai/10a), TOK (약량별 150g, 200g ia/10a), saturn(150g ai/10a), HE314, (250g ai/10a)의 4약제를 사용하여 1cm 복토심하에서 완주 봄보리에 대한 약해차이실험을 실시하였든바 그 결과를 요약하면 다음과 같다. 1. Machete 제형별(180g ai/10a 수준) 약해는 토양의 종류에 따라 심한 차이가 있었으며 식양토에서는 제형에 관계없이 거의 안전하나 사질 식양토<화산회양토<사양토 순위로 약해가 증대되었다. 유제의 약해의 입제의 약해보다 더욱 심하였다. 2. TOK 수화제 150g-200g ai/10a Machete와 거의 동일의 경향이며 약량이 높을 때 약해는 더욱 심하였다. 3. Saturn 150g ai/10a 토성에 따른 약해차이가 있기는 하나 그 차가 심하지는 아니하였다. 4. HE314. 250g ai/10a 250g 시용수준에서는 토성에 따른 약해차가 거의 없었다. III. 2종류의 토양을 대상으로 9개약제(TOK. MO. HE314, Machete, Saturn, Simetryne, Simazine, Gesaran Lorox)을 사용하여 복토심별(4단계)로 약해발생차이를 구명하였던바 그 결과를 요약하면 다음과 같다. 1. 경식ㅌ조건 : 1) Check에 있어서 복토심별 생육상황은 1cm>1.5cm>0.5cm>0cm의 순위였으며 0-0.5cm 복토구에 있어서는 보리 생육이 매우 불량하였다. 2) 약제처리구에 있어서도 0-0.5cm구에 있어서는 심한 해를 나타내고 있으며 1cm 이상의 복토가 유지될 때 보리에 비교적 안전한 약제는 Saturn, Machete, MO, TOK의 100-150g ai/10a, HE314 375-205g ai/10a구 등이었다. 3) 1.5 cm 복토에 있어서도 징해를 나타낸 약제는 Simazine, Lorox, Simetryne 등이었다. 2. 사질토조건 : 1) Cheick에 있어서 생육상황은 1.5cm>0.5cm>0.5cm>3cm>5cm의 순위이었다. 2) 약제처리구에 있어 MO는 1.5 cm 구에서 안전하였고 TOK의 약해는 1.5cm인때 가장 가벼운 편이다. 3) 3cm이상 복토가 될 때 비교적 안전한 약제는 Machete, Saturn 100g ai/10a, HE314 250g ai/10a 이었다. 4) 복토심에 구애없이 불안전한 약제는 Simazine, Lorox, Simetryne Gesaran 등이었다.