• Korean Journal of Construction Engineering and Management
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• v.10 no.5
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• pp.104-112
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• 2009

After the middle of 90's, the eco rivers maintenance enterprise was propelled about city rivers. The environmental function is more emphasized because of revising the rivers law enforced at 2008.4. Also, the field of application is being magnified. It is difficult to apply that the conceptual public work expense estimating model of the rivers which adjusts a focus at open channel rivers excepts the small-scale rivers maintenance public work. The research presents a eco rivers public work conceptual public work expense estimating model frame work. It suits the change of the rivers environmental renewal construction paradigm. It develops the conceptual public work expense estimating plan of the rivers at the planning phase using the collection and analysis of the data. As a result, riffle, spur dyke, stepping stones, fish way and etc are added. Consequently, it brings the hydrophilic function is considered seriously conceptual public work expense estimating model of the eco rivers.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.1
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• pp.183-194
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• 2019

In recent years, the risk of external flooding of major national facilities has increased significantly since 2000 due to the increase in local heavy rainfall events. For important domestic national facilities, it is necessary to analyze the risk of external flooding as flooding in major sites due to heavy rain can cause functional paralysis in major facilities and ultimately lead to massive trouble events. In order to manage the safety of main facilities and its related facilities at a high level, it is necessary to analyze the degree of disaster such as flood depth, flood flow rate, flood time and flood intensity when extreme floods (LIP) are introduced. In addition, the degree of vulnerability of these related facilities should be assessed and risk assessments should be reassessed through linkage analysis that combines the degree of disaster and vulnerability. By calculating a new flood hazard curve for the flood depth and flood intensity in major national facilities under the heavy rainfall conditions through this study, it is expected to be a basis for the waterproof design of important SOC facilities, flood prevention function design, advancement of flood prevention measures and procedures and evaluation of flood mitigation functions.

• Journal of the Korean GEO-environmental Society
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• v.10 no.3
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• pp.53-62
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• 2009

This study was conducted to investigate characteristics of the non-point source pollution under construction and evaluate available pollution control methods. Suspended solid loading is high when soil disturbs by rainfall and this phenomenon is much more severe at the initial stage of construction than at the final one. There are three methods available for erosion and sediment control, which are check dam, silt fence, and geotextile. Check dam and silt fence are for control of suspense solids and geotextile is for preventing soil erosion during rainfall. They can be installed as temporary control facilities at construction sites. From the comparison of those methods, it was found that geotextile method was the most efficient for the runoff control of non-point source pollution. Check dam and silt fence can remove suspense solids by pore spaces to some degree, but the removal of pollutants mainly occurs through sedimentation. Because the temporary control facilities have limited removal efficiency of pollutant, they often cause civil claims and contamination of water environment. Hence, using a pressurized filtration system along with temporary control facilities, highly enhanced treatment efficiency was anticipated. In addition, the loading capacity of these techniques depends on filtration velocity and input loading. And their pre-treatments are necessary for efficient operation.

• Korean Journal of Construction Engineering and Management
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• v.5 no.6 s.22
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• pp.203-211
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• 2004

This study is the results to survey on the problems and improvable Policies for current escalation system in construction contracts, through a Delphi survey to experts. From the survey results, it is desirable to decide the fluctuation rate of construction cost, which is the requirement of escalation clause, on the basis of inflation rate or construction cost index. The desirable price fluctuation rate is proposed as a $3\%$ level. However, it is difficult for construction companies to cope with the sudden increase of material price in advance, arising from short-term shock factors such as exchange rate and international raw material's price. Accordingly escalation system for specified materials, as an exceptional mode, should be introduced. As a method to calculate the fluctuation rate, ARCA(adjustment rate for the categories of articles) is more desirable than ARI(adjustment rate for an index), because the ARCA can be more reflected the characteristics of each construction work.To rationalize the ARI method, it is needed to announce the wage index, material index and machinery expense index via detailed classification by construction types. Also, it is desirable to prescribe the bidding date as a starting date of the price change, rather than contact signing date. considering the price change can happen since the biddiilg stage.

• Journal of the Korea Institute of Building Construction
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• v.11 no.2
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• pp.145-153
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• 2011

Since the early 1990s, Korean construction companies have strived to evolve into global Engineering Construction (EC) companies. However, such efforts have been unsuccessful, partly due to a lack of clear objectives and a misunderstanding of the direction that needed to be taken for such a change. A better understanding is required with respect to the need to transform into an EC company in the context of the rapidly changing global construction environment. This research investigates major EC companies from around the world, and assesses the status of domestic companies' efforts for EC transition. The results of these investigations revealed that domestic firms need to better prioritize their strengths for different markets, i.e., decide whether to implement directly, outsource or limit to process management. In addition, the investigations showed that the global market is shifting from monolithic projects to more complex projects. Such projects require firms with the ability to develop and implement high front-end investment strategies, planning capabilities, and pre-design management skills. Accordingly, we recommend that firms differentiate themselves by developing such a skill set required for specific products.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.8
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• pp.611-618
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• 2009

Road construction has been worked on by focusing on cost effectiveness such as the reduction of construction costs without understanding the natural environment and ecosystems. In addition, since ecosystems have been destroyed and the habitats of animals and plants have been isolated, wild animals have sought other habitats or have moved into isolated habitats. Thus, issues such as roadkills or the extermination of species are increasingly occurring. Based on this background, the development and application of a general assessment method need to be researched in order to verify whether or not spaces or habitats where animals can be inhabited and their species can be maintained exist. The purpose of this study is to develop an ecosystem map where a conservation value evaluation method considering the functions of an ecosystem where animals live as well as the naturalness of ecosystems is used and can be made into a drawing. The items applied to evaluate the habitat conservation values were naturalness, rarity, and functionality, and sub-items for evaluation were created. GIS as well as the evaluation items were used to create a digital map about the level of importance based on the evaluation criteria. The created digital map showed that it was not limited to the adjustment or distribution of the fauna and flora but was applicable for a general ecosystem evaluation method for the conservation of habitats. It is expected that the isolation of habitats would be able to be minimized if the digital map is used for road construction projects. The digital map is deemed to be able to be used for the construction of environmentally friendly roads, which will minimize the destruction of ecosystems and the isolation of habitats for creatures.

• Journal of the Korean Geotechnical Society
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• v.37 no.12
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• pp.7-23
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• 2021

Underground utility tunnels, which contribute to supply of electricity, communication, water and heat, are critical lifelines of an urban area. In case service is discontinued or functional disruption happens, there will be a huge socio-economic impact. For the improved seismic design and evaluation of underground structures, this study proposes a ground displacement measure when the site is subjected to a scenario earthquake based on hazard-consistent source spectra and site amplification/attenuation. This measure provides a rational estimation of ground displacement and can be an alternative to existing response displacement methods.

• Journal of the Korean Society for Precision Engineering
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• v.4 no.1
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• pp.9-20
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• 1987

지난해 우리나라는 주요 10대업종중 <조선>과 <건설>을 제외하고 대부분의 업종이 3저의 영향으로 생산, 내수, 수출등 제분야에서 고루 균형을 가진 호황의 한 해였다. 우리나라는 본원적으로 부존자원이 없는데다가 외채자본에 의존한 결과, 경제적 자립성을 유지하기 위해서는 부득이 해외시장에 의존하지 않을 수 없다. 그러기 때문에 정부는 지 금까지 수출주도형 고도성장정책을 견지해 왔으며 이 결과 국제수지의 적자와 물가상승등 부작용이 뒤따른것도 사실이다. 아뭏든 지난해의 우리나라 경제를 요약하면 경제성장- 물가안정-국제수지흑자로 이어졌는데 결국 세마리의 토끼를 한꺼번에 잡은 행운의 한 해 였음이 분명하다. 특히 값진 보람이라고 한다면 지금까지의 만성적인 국제수지적자가 추 방되고 사상초유의 흑자원년을 기록했다는 사실이다. 이렇게 볼 때, 우리기업인들은 행운이였다고 하기 이전에 주어진 기회를 재빠르게 포착하여 이용했다는 사실에서 그 저력을 과시하는 표현이 더욱 적절할 것 같다. 금년에도 또 몇마리의 토끼를 잡기 위해서는 고속성장보다는 안정된 기조하에서 수출주도형의 경제정책이 계속 밀고나가야할 것으로 생각 된다. 3저현상은 무한히 지속하는 것이 아니며 언제 무산될지 모르는 미래에 대비하여 사전 에 그 대응책이 마련되어야 하며 이 처방은 경쟁 우위력에서 구해내야할 것이다. 따라서 우리 는 축적된 경험과 <노우하우>를 바탕으로 품질의 고급화, 생산성향상, 부가가치의 증진등으로 선진국 대열에 진입할 수 있는 힘을 키워야 하며 이것은 오직 노사협조라는 평범한 진리에서 얻을 수 있다. 금년도 년초에 대통령의 국정연설에서 <올해는 우수한 기술. 기능인이 대폭 육성되고 이들이 산업현장에서 자기의 꿈을 키울 수 있도록 더욱 효과있는 지원제도를 발전해 나갈 것이다...>라고 하였고 또 <이같은 과학기술의 진흥과 산업현장의 기술. 기능인력을 양 성하는 데 역점을 둔다...>는 최고지도자의 구상은 바로 우리가 기대했던 공감대를 형성하였 다고 본다.

• Magazine of the Korea Institute for Structural Maintenance and Inspection
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• v.16 no.2
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• pp.74-86
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• 2012

이태리를 비롯한 대부분의 유럽 국가들에 건설된 많은 기존 도로 및 철도 교량들 중에는 현재의 구조설계기준이나 교통시스템, 유지관리비용 절감 등을 고려한 요구조건과 비교했을 때 구조적 안전성과 기능성을 만족시키지 못하는 경우가 종종 있다. 따라서 어떤 형식의 교량이든 특정 취약성을 평가할 수 있는 신속하고 신뢰성 있는 방법론이 필요하다. 이 논문의 앞부분은 이태리 내 도로 및 철도 구조물에 대해 그런 형태의 방법론의 적용에 대해 기술하였으며, 그 결과를 보면, 한 예로 조적조 아치 교량이 일반적으로 상당히 건전한 구조 시스템으로 나타났으며 RC 교량은 일반적으로 내구성 문제를 드러내며 지진하중에 대해서도 취약한 것으로 나타났다. 강교량은 내구성 문제 외에 피로에 특히 취약한 것으로 나타났다. 그리고 이 논문에서 고려한 전형적인 보강기법들에 대해 간략히 소개하였다. 뒷부분에서는 네 개의 기존 RC교량을 중심으로 주요 교량보강 사례연구들에 대해 좀 더 자세히 기술하였다. 이 교량들은 2차 세계대전 이후에 가장 일반적으로 채택되던 형식들 중의 한 예로 보강기법의 일반적 성질을 고찰하는데 있어 적합하다. 교량의 성능개선에 대해서는 방법론적 접근에 대해 개략적으로 나타내었으며, 여기에는 구조물의 유형적 특성, 유지관리 현황, 기능적 요구조건 및 보수 보강 시스템과 연계된 환경적인 면을 고려하고 있다.

• The Journal of Engineering Geology
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• v.5 no.3
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• pp.289-300
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• 1995

At the initial stage of the underground reservoir design one should thoroughly consider surface and subsurface hydrology, hydrogeologic characteristics of aquifer system, and the function of cut - off wall because it is linked to the effective management. In this study, three dimensional finite difference model was applied to analyse the function of Ian underground reservoir at Kyungbuk Province. The steady and unsteady state conditions after construction of the underground dam were simulated through the model, and from these results the groundwater budget and the safe yield were determined. The model simulation indicates the infiltration of irrigation water to be one of the major factors of seasonal fluctuation of groundwater level. The recharge rates of irrigation water were estimated as 4.3mm/d during May and June, and 1.7mm/d during July and Agust. Groundwater recharge from the watershed area estimated to about $0.04m^3/s$, almost consistent through the year. In 1984, groundwater discharge through the transverse section of the dam was $0.002m^3/s$ and the optimum yield for two momths(July and Aguest)was $254000m^3$, however, the discharge became $0.013m^3/s$ in1993, implying the failure of cut -off function. without appropaiate of the cut - off wall, optiumum yield during the irrigaton period would be $93, 000m^3$.