• Journal of the Korean Geosynthetics Society
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• v.17 no.4
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• pp.225-238
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• 2018

In this paper, to investigate the influence of installation damage, a variety of full-scale field installation tests with 15 geosynthetics reinforcements and fill materials of various grain size distribution have been performed. The full-scale field installation test was conducted with reference to the FHWA (2009) guidelines. The tensile strength tests were performed by sampling up to 20 specimens randomly from the excavated geosynthetics reinforcements after compaction of fill material, and the degree of decrease in tensile strength of reinforcements due to compaction was analyzed based on the experiment results. It was found that the degree of tensile strength reduction of geosynthetics reinforcements due to the compaction of fill material is greatly influenced by the type of reinforcement and the maximum diameter of fill material. In addition, it was found that the strength reduction ratio of PET geogrid (PVC coating) with relatively small stiffness was greatest, and that the larger the maximum grain size of the fill material, the greater the strength reduction ratio. And also, a more reasonable evaluation method for the installation damage reduction factor of geosynthetics reinforcements is proposed based on the results of full-scale field installation tests in present study and the existing test results.

• Korean Journal of Construction Engineering and Management
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• v.23 no.2
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• pp.95-101
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• 2022

This study attempts to identify the ways of reducing the floor impact sound, by applying six different types of the reinforced bar girders and stirrup arrangements to the Structure: (1) the longer-direction girder arrangements (2) the shorter-direction girder arrangements (3) the diagonal-direction arrangements (4) the longer-direction girder arrangements with stirrups (5) the shorter-direction girder arrangements with stirrups (6) the diagonal-direction arrangements with stirrups. In order to identify the most effective structural changes, each slab was tested with bang machines, measuring the level of the sound impact. The results showed that the longer-direction girder arrangements with stirrups were the most effective one. In addition, the effectiveness of slab was found to be remarkable, showing the level of minimum 1dB to maximum 5dB, where the slab was compared with the control models without girders and stirrups. In conclusion, it is suggested that the longer-direction girder arrangements with stirrups could possibly be applied to the Wall Structures to minimize the floor impact sound.

• Plant Journal
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• v.11 no.3
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• pp.32-45
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• 2015

중동지역을 필두로 하여, 국내건설사들은 시공분야에서의 높은 경쟁력을 바탕으로 매년 놀라운 속도로 해외 플랜트 EPC 건설시장에서의 점유율을 높여 나가고 있다. 2012년에는 전 세계 건설시장의 8.1%를 점유하며, 이탈리아를 제치고 역대 최고인 세계 6위의 건설 강국으로서의 면모를 과시하기도 하였다. 그럼에도 불구하고, 그간 수주 자체를 목적으로 한 저가입찰 등과 같이 리스크를 간과한 무리한 수주는 폭탄의 뇌관을 건드리는 격이 되었고, 결국 2013년 일부 대형 건설업체들은 해외 사업장에서 대규모 손실을 경험하였다. 이와 더불어, 해외 대규모 EPC 플랜트 사업의 수주금액이 급증하여 한 개의 사업에서 발생되는 손실이 기업의 총체적 경영에도 큰 영향을 미칠 수 있게 됨에 따라, EPC 플랜트 건설사업의 잠재 손실의 원인을 최소화하고 건설사들의 지속적인 성장을 가능하게하기 위해서 리스크를 효율적으로 관리해야 하는 필요성은 더욱 증가하였다. 따라서, 본 연구에서는 해외건설시장 중, 중동지역에서 EPC 형태로 발주되는 발전플랜트 건설사업의 리스크 요인들을 발굴하고, AHP (Analytic Hierarchy Process) 기법을 사용하여 리스크 요인들 간의 우선순위를 정량적으로 도출하여, 국내건설사들이 중동지역의 EPC 사업수행 현장에서 효율적으로 리스크를 관리할 수 있도록 도움을 주고자 하였다.

• Tunnel and Underground Space
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• v.9 no.2
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• pp.114-130
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• 1999

It is very important to study on the structural behaviors of structurally damaged tunnel linings. A series of centrifuge model tests were performed in order to investigate different behaviors of tunnel linings. A 1/100-scaled aluminum horseshoe tunnel linings with a radius 5 cm, height 8 cm were buried in a depth with dry Joomunjin standard sand, the relative density of which was 86%. Such sectional forces as bending moments and thrusts along the tunnel circumference were measured by twelve strain gages. Earth pressures in soil mass and on the outside of lining model were estimated by pressure transducers, ground surface settlements at a center and edges by using LVDTs.

• Journal of the Korea Institute of Building Construction
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• v.12 no.3
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• pp.257-265
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• 2012

Many construction companies are simultaneously carrying out numerous projects in the housing construction industry. It is essential to accurately forecast the cash flow of a project through optimal process management and resource input in order to manage funds rationally and enhance the competitiveness of a company. Current cash flow forecasting methods offer lower accuracy due to a large gap between the revenue and expenditure element. Expenditure elements depends on the real-time changing actual cost for work performed. This research survey was conducted on the actual state of construction management of K company to investigate the problems of cash flow forecasting. To achieve this, the work process and construction management system were integrated to improve the cost management system of K company. To accurately forecast the cash flow of a project, revenue and expenditure elements were displayed in the total cash flow forecast window. This research is expected to assist in the implementation of a system of cash flow forecasting on housing construction by excluding negative elements of revenue and expenditure.

• Journal of the Korea Institute of Building Construction
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• v.11 no.2
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• pp.154-161
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• 2011

In increasingly competitive market conditions, domestic construction companies are struggling to secure a competitive edge by increasing consumer satisfaction. In these circumstances, a greater emphasis needs to be put on providing an upgraded level of quality in the area of addressing defects to the satisfaction of customers, which is considered to have a great impact on customer satisfaction. This empirical study of the relationships among service quality, customer satisfaction, and repurchase intention aims to provide basis data for increasing service quality, particularly in dealing with the defect issues facing construction companies. To this end, a literature review was carried out on the concept of service quality along with defect issues, and customer satisfaction and influential factors were identified. Building on these foundations and findings, a survey was administered to residents in housing dwellings such as apartments. The results of this study are expected to heighten awareness of the need for increased service quality, which may have a critical influence on customer satisfaction and repurchase intention, and will thereby contribute to enhancing competitiveness and other aspects of the current construction industry.

• Journal of Cadastre & Land InformatiX
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• v.44 no.2
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• pp.231-242
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• 2014

On the Pre-Housing-Sale Systems there are many risks that developers might not fulfill the pre-sale obligations. In korea, in order to protect the people who bought houses from these risk, the Housing Sold Guarantee System was introduced and has been operated. Even though this system if there is accident in the pre-sale warranty business, several problems, such as damages caused to the people who bought the houses, occurs. Therefore, research is needed to Housing Sold Guarantee accident factor. But there are few study about it. This study attempted to analyze influencers on the possibility of the accident. We employ 3,026 data which Korea Housing Guarantee Co., Ltd manages and analyze them empirically, using business characteristics, housing market characteristics, and regional characteristics. Especially this study used to the binary logistic regression model. The results of analysis showed that the accident rate of Housing Sold Guarantee had been effected on the business type, house type, project financing guarantee, operator credit rating, housing market, and regional characteristics.

• Plant Journal
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• v.11 no.1
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• pp.30-38
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• 2015

This study is about whether the new Project Finance scheme called "Asset Backed Short Term Bond(ABSTB)" with Project Finance Guarantee Cover provided by Korean Exim Bank(KEXIM) is an appropriate and valid financing structure, through close examinations on domestic and overseas IPP case studies. This study clearly indicates that (i) the interest rate of ABSTB with KEXIM's Project Finance Guarantee is relatively more competitive than the interest rate of other ABSTB guaranteed by EPC Companies (ii) the lower credit rated EPC companies make higher ROE(Return on Equity) through this financing structure. Lastly, Korean EPC Companies can secure profitability through this innovative financing scheme which will also lead to winning more power plant Contracts and become globally competitive.

• Korean Journal of Construction Engineering and Management
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• v.14 no.2
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• pp.150-159
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• 2013

The government has focused on activation of overseas construction projects and strengthening competitiveness in the long term. In recent years Public construction contract as well as design, engineering, construction management(CM) are gradually expanding into other countries, but risk analysis cases in the field are slight. In this study, We utilized PI scale and drew a conclusion about the importance of overseas risk by participants. We compared its features from the risk factor based on Risk Matrix. As a result of this study total of 6 section 31 Country Risk factors for the importance of overseas risk by participants were drawn, and the key risk factors (17 constructor, 14 designers, 17 CMr) based on Risk Matrix were derived. By utilizing the result of this study will be used as the basic data for establishing risk management strategy to meet each business and planning evaluation model.

• Korean Journal of Construction Engineering and Management
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• v.18 no.3
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• pp.22-32
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• 2017

Judging from the past cases, the contractor has frequently suffered losses caused by disapproved requests or reduced payments since it has not known the conditions of the contract or it has filed a claim to the owner without any proper claim system. Therefore, the existing claim process needs to be reformed. In order to reform the claim process, the contractor should consolidate the organizational structure, grant accurate duty assignments to the claims manager, implement regular staff training on how to deal with claims. In addition to this reformation, the contractor needs to improve the management of construction period and process control, and manage related documents thoroughly. Regular meetings are also necessary in claims. This study attempts to prove the effectiveness of the reformed process applied to Project "A", where the owner was responsible for the delayed supply of materials, inaccurate oral instructions, insufficient information on the work, and frequent changes of design. The project was completed in 96 months, which was extended by 34 months from the initial construction period of 62 months. The reformed claim process is expected to be of great help not only to largescale construction works but also to smallscale ones.