• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.1695-1704
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• 2008

The problems associated with constructing high-speed concrete track embankments over soft compressible soil has lead to the development and/or extensive use of many of the ground improvement techniques used today. Drains, surcharge loading, and geosynthetic reinforcement, have all been used to solve the settlement and embankment stability issues associated with construction on soft soils. However, when time constraints are critical to the success of the project, owners have resorted to another innovative approach. Especially, the design criteria of residual settlement is limited as 30mm for concrete track embankment, it is very difficult to satisfy this standard using the former construction method. Pile net method consist of vertical columns that are designed to transfer the load of the embankment through the soft compressible soil layer to a firm foundation and one or more layers of geosynthetic reinforcement placed between the top of the columns and the bottom of the embankment. This paper will present the guidelines for the design of pile net method to supported embankments. These guidelines were developed based on a review of current design methodologies and a parametric study of design variables using numerical modeling.

• 대한조선학회논문집
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• 제46권3호
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• pp.325-334
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• 2009

Generally, functional design of FPSO has been done by the engineering firm designated by ship owner. Main equipment such as topside facility is imported from abroad. But sometimes, OFE (Owner Furnished Equipment) does not satisfy the PND (Product Need Date) of each production stage because the delivery date of OFE is not scheduled to satisfy the PND. And sometimes many loose items and equipment are complex from engineering which does not consider pre-outfitting. Main objective of this study is process improvements by maximizing pre-outfitting rate in the stage of equipping STP (Submerged Turret Production), one of main equipment on FPSO. In this study, we analyzed the factors which obstructed pre-equipping STP using the past records of FPSO projects.

• 대한산업공학회지
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• 제42권4호
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• pp.270-279
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• 2016

A glass product manufacturing company transports a large number of flat glass products from a manufacturing firm to a building construction site. The products are transported using specially designed racks, which assure fewer glass breakages during the deliveries. This study determines the sizes of the racks which minimize the total logistics cost including costs for rack purchasing, handling, transportation, and inventory costs. The determination of the rack size should consider tradeoff relationships between the amount of glasses piled in a rack and the number of racks loaded on a truck, and affects the required number of racks and the truck operational cost. A truck loading algorithm is proposed to maximize a high truck utilization, and an enumeration method is proposed to determine the optimal combination of rack sizes considering the total logistics cost. The numerical example is solved by using a real data.

• Steel and Composite Structures
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• 제50권4호
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• pp.419-428
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• 2024

Prefabricated partially-encased composite (PEC) structural component is widely used in construction industry due to its superior structural performance and easy assembly characteristic. However, the solid web in traditional PEC components tends to split concrete into two halves, thus potentially reduces structural integrity and requires double concrete pouring. To overcome the above disadvantages, a new PEC beam with open-web π-shaped steel is proposed in this paper. Four open-web PEC beams with varying sectional height, flange thickness and web void rate were constructed and tested under flexural loads. During experimental tests, all beams exhibited typical flexural failure modes with strong moment capacities and excellent ductility. Owing to the unique construction form of web opening, steel-concrete bonding properties were enhanced and very small relative steel-concrete slips were observed. Experimental results also showed that the flexural capacity of such PEC beams increased with the increase of the sectional height and flange thickness, while was not affected by the web void rate. At last, a flexural capacity formula of the open-web PEC beam was proposed based on the whole section plastic rule. The formula results agreed well with experimental results.

• 한국건설관리학회논문집
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• 제14권5호
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• pp.122-130
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• 2013

CM시장에서의 경쟁이 심화되고 있는 상황에서 CM기업이 경쟁우위를 점하는 것은 매우 중요한 기업 현안이다. 이를 위해서는 적합한 경쟁전략을 갖추어야 하고 이를 통해 지속적으로 경쟁우위를 확보할 필요가 있다. 본 연구의 목적은 CM시장에서 경쟁우위를 점하기 위해 CM기업들이 중요하게 여기는 경쟁전략요소를 분석하고 이들 경쟁전략요소에서 나타나는 주요 특징과 시사점을 도출하는데 있으며 마이클 포터(Michael Porter)의 경쟁전략모델을 분석방법론으로 활용하였다. 연구 결과, 상위그룹에서는 차별화전략을 중요시 여기는 반면, 하위그룹에서는 집중화전략을 중요시 여기는 것으로 나타났다. 그러나 원가우위전략은 상하위 그룹에서 동일하게 상대적으로 중요도가 낮은 경쟁전략으로 인식되고 있는 것으로 나타났다. 비록 상하위 그룹에 따라 각 경쟁전략요소의 세부적인 순위에는 차이가 있었지만 종합적으로 보면 특화된 CM서비스 제공이 중요한 경쟁전략요소로 인식되고 있었다. CM기업의 경쟁전략요소에 대한 이해는 현재 CM기업들이 중요하게 생각하는 경쟁전략의 방향성과 내용을 파악할 수 있게 하며 향후 자사(自社)의 경쟁전략 수립을 위해 유용하게 활용될 수 있다.

• 한국건설관리학회논문집
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• 제19권1호
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• pp.74-79
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• 2018

적정한 낙찰률을 유도하는 제도의 수립은 시설물의 품질보장과 기업의 합리적인 이윤추구를 위해 매우 중요하다. 하지만 과거 낙찰제도의 변화와 최근 사례를 통해 덤핑이나 고가낙찰 등이 남아있어 부실공사, 기업의 적자 또는 세금낭비 등을 유발하고 있는 것을 볼 수 있다. 본 연구는 낙찰률 형성의 배경을 파악하고 기업의 입찰행태에 대한 이해를 증진하기 위해 실제 입찰시장의 데이터를 분석하였다. 투찰률에 각 변수가 주는 영향을 파악하기 위하여 다중회귀분석을 실시하였다. 특히 기업규모를 세분화하여 분석함으로써 기업규모별 상이한 투찰행태를 함께 확인하고자 하였다. 그 결과 사업규모의 경우 모든 기업규모에서 투찰률과 양의 상관관계를 보였으나 연간발주규모, 시공능력평가액의 경우 중소기업과 대기업이 투찰률에 대하여 서로 상반되는 상관관계를 보였다. 본 연구의 결과를 통해 제시된 여러 변수들이 기업이 입찰행위를 함에 있어서 실질적으로 영향을 미치고 있다는 것과 같은 변수라도 기업규모에 따라 투찰률에 영향을 주지않거나 각기 다른 상관관계를 보임을 알 수 있었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2009년도 춘계 학술논문 발표대회 학계
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• pp.247-252
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• 2009

The LMC method of construction which have application to the road bridge is being considered the least relative importance about the watertight performance, because it focused on the durability of concrete. However, The LMC which is being expanded scope of application to the method of construction has grown importance about the watertight performance on the usability and maintenance side as well as durability. In this study, The latex concrete of two types which are different from mingled-ratio of the latex made a comparison to the compressive strength, watertight performance, dynamic wheel load resistance performance and confirmed what it has resistibility about chemical action through the chemical resistance test. The initial strength and watertight performance showed that were tendency the downward at 14 days. However, The long-term strength after 28 days showed that it has firm performance. In consequence, The initial curing of latex concrete is required to scrupulous care and attention at the site application. As a chemical resistance test result, The specimen that is steeped in sulphuric acid solution of 2% discovered the delamination phenomenon. However, it was confirmed that delamination phenomenon don't have an effect on the compressive strength. Moreover, As a dynamic wheel load resistance test result, The latex concrete was concluded to confirming the durability and running stability, because it had hardly any thickness reduction of latex concrete surface about dynamic wheel load and rarely found crack and delamination.

• 한국안전학회지
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• 제20권3호
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• pp.120-125
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• 2005

Formwork is a temporary structure that supports its weight and that of freshly placed concrete as well as construction live loads. Among the accidents and failures that occur during concrete construction, many are formwork failures which usually happen at the time concrete is being placed. In constructions site, pipe supports are usually used as shores which are consisted of the slab formwork. The strength of a pipe support is decreasing as it is frequently being used at the construction site. The objective of this study is to find out the strength change of used pipe support and unused pipe supports according to aging. In this study, 2857 pipe supports were prepared. Among these pipe supports, 2337 pipe supports were lent to the construction companies fire of charge. 520 pipe supports were kept on the outside. Compressive strength was measured by knife edge test and plate test at each 3 month. Test results show that the strength of unused pipe supports as well as used pipe supports was decreasing according to age, use frequency and load carrier, and the strength of used pipe supports was lower than the strength of unused pipe supports at the same age. So, the strength of used pipe supports from 191 days to present day was not satisfied the specification of KS F 8001. According to these results, it shows that attention has to be paid to formwork design using used pipe supports. Therefore, the present study results will be able to provide a firm base to prevent formwork collapses.

• 기술경영경제학회:학술대회논문집
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• 기술경영경제학회 1996년도 제10회 동계학술발표회 논문집
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• pp.99-117
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• 1996

본 논문은 기업내의 수직적 기술이전 문제를 다룬 사례연구로서 한 건설업체의 연구소에서 이루어진 기술개발 결과가 사업부문의 현장에 이전 활용되는 과정에서 기술이전 정도가 어떤 요인에 의해 영향을 받는지 분석하였다. 사례분석 결과 D건설의 경우 기술이전팀 및 프로젝트 추진자(Project Champion)의 존재여부가 기술이전의 성패에 가장 큰 영향을 미치는 것으로 나타났으며 최고경영자의 적극적인 지원도 성공적인 기술이전에 강한 긍정적인 요인이 되는 것으로 분석되었다. 또한 당초 사례분석의 틀에서 고려하지 않았던 기술인지도나 기술수용자의 시장평가가 기술수용 노력에 영향을 미치는 것으로 분석되었다. 사내기술이전시 이러한 요인들을 고려한다면 보다 효과적인 기술이전이 될 것으로 기대된다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(II)
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• pp.277-284
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• 2003

To meet demand for large-scale new personnel caused by active railway investment projects such as high-speed line construction, electrification and double-tracking of the existing lines, we KNR need to establish a subsidiary firm for each field instead of personnel augmentation. The establishment of subsidiaries is expected to solve the problem of the current outsourcing services, reduce costs and in the long term, improve the efficiency of railway business. In addition, we also suggest, as a pilot project, setting up Korean Freight Inspection Company in charge of conducting light and heavy maintenance for freight cars.