• 제목/요약/키워드: Soil problems

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지반-구조물의 상호작용 해석을 위한 무한요소 (Infinite Elements for Soil-Structure Interaction Anaysis)

  • 양신추;윤정방
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1989년도 봄 학술발표회 논문집
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    • pp.22-27
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    • 1989
  • This paper presents a study of soil-structure interaction problems using infinite elements. The infinite elements are formulated for homogeneous and layered soil media, based on approximate expressions for three components of propagating waves, namely Rayleigh, compressive and shear waves. The integration scheme which was proposed for problems with single wave component by Zienkiewicz is expanded to the multi-wave problem. Verifications are carried out on rigid circular footings which are placed on and embedded in elastic half space. Numerical analysis is performed for a containment structure of a nuclear power plant subjected seismic excitation.

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SIP공법 시공시 문제점 발생 요인 분석 및 대응 방안 (Analysis and Countermeasures for the Problem Arise of the Spot Installation Pile Using SIP)

  • 박종혁;박홍태;전용배
    • 한국산학기술학회논문지
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    • 제12권7호
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    • pp.3287-3295
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    • 2011
  • 현재 건설현장에서 매입말뚝공법인 SIP(Soil-cement Injected Precast pile)공법이 널리 활용되고 있다. 그러나 SIP공법 시공시 문제점 발생 요인들로 말뚝의 품질이 저하되거나 부실시공이 빈번히 발생하고 있다. 본 연구에서는 이 문제를 줄이는 방법으로 SIP공법을 중심으로 시공할 때 문제점 발생 요인 종류별로 현장 기술자들을 대상으로 설문조사를 수행하였다. 그리고 설문 분석 결과를 토대로 문제점 종류별로 자주 발생되는 문제점 요인을 분석함으로써 대응 방안을 제시하였다. 본 연구에서 제시한 문제점 요인별 대책은 향후 건설현장에서 SIP공법으로 시공할 때, 문제점을 최소화할 수 있는 효과적인 자료가 될 것으로 사료된다.

인삼 연작장해 연구에 대한 고찰 (Review of Studies on Ginseng Replanting Problems)

  • 이종철;김홍진;오승환
    • 한국작물학회지
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    • 제34권s02호
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    • pp.115-120
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    • 1989
  • 인삼의 연작장해의 증상, 원인 및 방제법에 대하여 고찰하였다. 1. 연작장해의 증상은 인삼의 생장억제 근부에 의한 근수량 저하였으며 품질에는 영향을 주지 않았다. 2. 연작장해는 토양병원미생물과 인삼유체 분해산물의 식물에 대한 직접적인 독작용, 그리고 이들 유체 및 그 분해산물에 희한 토양내 전속화합물의 용해 또는 결합에 따른 전속이온의 식물에 대한 독작용 등이 상호 복합적으로 나타난 것으로 보인다. 3. 토양은 근부유발형과 근부억제형 토양으로 구분되며, 토양이화학성이 연작장해를 조장시키지는 않았다. 4. 연작장해의 방제법은 살균제에 의한 효과는 기대하기 어렵고, 훈증제(싸이론, 크로로피크린)를 처리하여 연작할 경우 고년근에서 근부병 발생이 심하기 때문에 훈증제와 길항미생물의 혼합처리가 효과적이다. 또 답전윤환이 가능한 논에서 3∼4년간 벼를 재배한 후 인삼을 연작하는 방법이 실용화되고 있다.

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MTBE에 의한 지하수 오염

  • 조종수
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2001년도 추계학술발표회
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    • pp.9-12
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    • 2001
  • MTBE is a gasoline additive which is widely used in the world. Its use on the air pollution reduction has been proved very effective, but has generated serious problems of groundwater contamination. Its use will be banned gradually by US EPA and other states governments in US. In Korea, it has been used since 1987 and its consumption reaches about 700, 000 tons/year. Any problems related to the groundwater contamination has not been reported in Korea, yet due to the lack of investigation. In this presentation, I raise the MTBE problems with examples of MTBE contaminations in the US.

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Application of an Optimization Method to Groundwater Contamination Problems

  • Ko, Nak-Youl;Lee, Jin-Yong;Lee, Kang-Kun
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2002년도 추계학술발표회
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    • pp.24-27
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    • 2002
  • The optimal designs of groundwater problems of contaminant containment and cleanup using linear programming and genetic algorithm are provided. In the containment problem, genetic algorithm shows the superior feature to linear programming. In cleanup problem, genetic algorithm makes reasonable optimal design. Un this study, it is demonstrated through numerical experiments that genetic algorithm can be applied to remedial designs of groundwater problems.

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Abandoned Landfills in Indonesia and Their Problems

  • Ling, Marisa Mei;Park, Jun-Boum
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제14권4호
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    • pp.1-9
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    • 2009
  • This paper presents current condition of landfills in Indonesia and the problems exist. It also presents a review of study on abandoned landfill in Bandung, West Java where the actual problems can be seen and an insight to the solutions were developed.

화학사고시 토양오염 사전관리제도 도입을 위한 국내외 제도 분석 및 시사점 (A Study on the Introduction of Pre-management System to Prevent Soil Contamination by Chemical Accident)

  • 유근제;양지훈;황상일
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제21권4호
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    • pp.20-29
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    • 2016
  • Although a number of chemical accidents have been occurred in South Korea, the effective prevention act for soil contamination has not been established so far. To effectively protect soil contamination from chemical accidents, decision support laws and regulations are absolutely essential. Regarding this situation, this study was aimed at diagnosing problems in current chemical safety management and prevention and response system against chemical accidents through analyzing the domestic and foreign causes of chemical accidents and the accident response procedures and finally suggesting policy measures for solving those problems. In order to clarify management of soil contamination by chemical accident, this study suggests the establishment of chemical accident preparedness, response, and making of local chemical management law and policy. This law needs to be supported by a clear management framework to guide government officials and all other stakeholders in the management of soil contamination by chemical accident.

Probabilistic optimization of nailing system for soil walls in uncertain condition

  • Mitra Jafarbeglou;Farzin Kalantary
    • Geomechanics and Engineering
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    • 제34권6호
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    • pp.597-609
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    • 2023
  • One of the applicable methods for the stabilization of soil walls is the nailing system which consists of tensile struts. The stability and safety of soil nail wall systems are influenced by the geometrical parameters of the nailing system. Generally, the determination of nailing parameters in order to achieve optimal performance of the nailing system for the safety of soil walls is defined in the framework of optimization problems. Also, according to the various uncertainty in the mechanical parameters of soil structures, it is necessary to evaluate the reliability of the system as a probabilistic problem. In this paper, the optimal design of the nailing system is carried out in deterministic and probabilistic cases using meta-heuristic and reliability-based design optimization methods. The colliding body optimization algorithm and first-order reliability method are used for optimization and reliability analysis problems, respectively. The objective function is defined based on the total cost of nails and safety factors and reliability index are selected as constraints. The mechanical properties of the nailing system are selected as design variables and the mechanical properties of the soil are selected as random variables. The results show that the reliability of the optimally designed soil nail system is very sensitive to uncertainty in soil mechanical parameters. Also, the design results are affected by uncertainties in soil mechanical parameters due to the values of safety factors. Reliability-based design optimization results show that a nailing system can be designed for the expected level of reliability and failure probability.

한국 토착유기농업의 토양비옥도 증진책의 문제점과 대안 (Problems and Solutions of Soil Fertility Enhancement in Korean Organic Farming)

  • 손상목
    • 한국유기농업학회지
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    • 제8권2호
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    • pp.53-77
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    • 2000
  • This paper aims to point out the problems and solutions of soil fertility enhancement in Korean organic farming which does not harmonize with internationally recognized standard of organic agriculture such as Basic Standard of IFOAM, EU regulations, and guidelines of FAO/WHO codex alimentarius. The necessity of rotation, legume, green manure to enhance the soil fertility or organic farming system was discussed, and the reasons why salt accumulation including nitrate and phosphate in the rooted soil profiles was frequently occurred in Korean organic farmer's field also discussed. Soil testing for correct handling of organic fertilization was introduced to void the salt accumulation just applying the huge amount of organic fertilizer year to year to reach a maximum crop yield. In the conclusion it was suggested for Korean organic agriculture to make an effort to coincide it's regulation with internationally recognized standards for organic farming.

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