• Journal of Welding and Joining
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• v.16 no.1
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• pp.25-37
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• 1998

본 해설에서는 Inconel계와 Hastelloy계로 구분되는 9%Ni강용 피복아크용접봉을 중심으로 LNG저장탱크 용접시공시 발생 가능한 문제점들을 검토하고, Ni합금 피복봉의 심선과 피복제와 관련한 일반적인 제조특성을 살펴보았다. 또한 현재 국내 현장에서 용접시공에 사용되는 용접재료의 화학적, 기계적 특성과 함께 용접작업성을 평가한 결과 이들 피복아크용접봉들은 규격이 정한 요구조건들을 만족하면서 비교적 양호한 용접작업성을 확보하고 있는 것으롤 판단되었다. 이상의 검토결과는 향후 9%Ni강용 Ni합금 피복아크용접봉의 국산화 개발에 기초자료로 활용될 것으로 기대된다.

• Journal of the Korea Institute of Building Construction
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• v.16 no.3
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• pp.211-217
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• 2016

In this research, the performance of surface covering technique using a white-colored bubble sheet on reducing the cracking due to the plastic, and drying shrinkages for high rise building construction were evaluated by comparing the exposed surface without any surface treatment. From the results of the experiment conducted during fall season, desired results of decreased numbers, length, maximum width, and area of cracking were obtained without a significant difference on heat of hydration and cumulative temperature. Therefore, it is considered that the surface covering technique using bubble sheet is an appropriate method for preventing plastic and drying shrinkage cracking at fall season concrete construction.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.3
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• pp.190-198
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• 2018

The Epoxy-coated Reinforcing bars have been proved to be able to extend a durability life because of its excellent corrosion resistance in bridges and structures under marine and severe environments. The usage of epoxy-coated reinforcement is continuously increasing in developed countries such as the US and Japan. However, domestic use is extremely limited due to lack of research and development, poor production facilities, low quality, increase of initial costs, and difficulty of field management. This study suggests the improvement of construction quality management such as manufacturing, transportation and construction for the field application through the test construction of the proven product in the related test results of the epoxy coated steel bars produced in the recently improved manufacturing facility.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2000.09a
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• pp.171-175
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• 2000

국내 시공사례가 가장 많은 사석식 경사제는 피복층(cover layer), 중간피복층(underlayer), 그리고 내부사석(core and bedding layer)으로 이루어져 있다. 이 중 중간피복층의 재료는, 피복재의 중량(W)에 대한 중량비 W/10에서 W/15의 자연석을 이용하여 시공하는 것이 보통이다. 그러나, 항만의 대형화에 따른 설계파의 증가로 이형블록과 같은 피복재의 소요 중량이 증가하는 추세이며 이에 따른 중간피복재의 소요중량도 크게 되어 그에 만즌 자연석을 구하기 어려운 실정이다. (중략)

• Proceedings of the KIEE Conference
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• 2008.04b
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• pp.197-199
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• 2008

전연전선을 핀애자에 고정하기 위해 피복바인드선을 사용하고 있는데, 오손지역에서 전선피복과 바인드 사이에서 트래킹으로 인하여 단선고장이 간혹 발생하고 있다. 과거 간접 활선시 사용하던 핫스틱(Hot-stick) 공법에 필요한 바인드 고리의 불필요성이 검토되었고 이러한 고리가 바인드선 내 순환전류를 제공하여 주울열에 의해 전선의 피복에 손상이 발생한다는 의견이 제기되었다. 본 논문에서는 절연전선의 바인드 끝단 형태를 변경하여 전선피복에 대한 침식 영향을 평가하였다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.169-170
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• 2012

It is analyzed that constructability of post-tensioning system applying HDPE greased strand that is greased and coated by high density polyethylene on a bare strand in reactor containment building. The improvement of corrosion resistance by greasing and HDPE coating on a strand makes transportation, handling and installation of tendon to be easier. Therefore, serial and repetitive process of post-tensioning composed of construction preparation, tendon installation, stressing and anchoring, grease injection could be improved parallel and lumping process of installation and grouting, stressing and anchoring.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.185-191
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• 2009

The construction of experimental greenhouses, operating test, and analysis on variation of different environment factors were conducted to provide fundamental data for design of Korean style air-inflated double-layer plastic greenhouse. The development of technology of attaching plastic to the structure and fasteners to be able to keep airtight was required in order to maintain proper static pressure in air space of double layer coverings. The insulation effect of air inflated greenhouse was better than conventional type. The temperature of arch type roof was greater about $2^{\circ}C$ than peach type roof in air inflated greenhouse. It was recommended that the plastic should be attached at the edges without clearance length in order to ease installation and raise airtightness of double layer coverings. The transmittance of arch type roof was greater than peach type in air inflated one span greenhouse. The transmittance of air inflated greenhouse was greater than conventional type due to frame ratio and distance between double layers in three span greenhouse. The condensation occurred on conventional type greenhouse was more than air inflated type. It was required to examine for a long time in order to analyze it quantitatively.

• Journal of Korean Society of Steel Construction
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• v.27 no.1
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• pp.43-52
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• 2015

Constructions of buildings downtown are increasing as much as ever with a strong demand. Top-Down Method is suitable for its advantage in minimizing its disturbance to the neighborhood. Pre-founded when applied to CFT Column on-site welded is required for splicing. To complement the welded built-up square composite Column was developed. Top-down process will be pouring concrete in accordance with a step-by-step process. Thus, Pre-founded Column and cover concrete to determine the stress condition. Therefore, Concrete filled steel square tubular columns encased with precast concrete were studied. Five Centrally loaded Columns were tested to investigate the axial load carrying capacity. we analyzed the strength and behavior of CET Column by Loading conditions and concrete strength, thickness of cover concrete through structure experiments.

• Journal of Korean Society of Forest Science
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• v.104 no.2
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• pp.206-212
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• 2015

This study was carried out to assess the characteristics of gabion on road cut-slopes, and analyze the scenic view preference for the gabion in Korea. 97 gabion sites from road cut-slopes were selected and were classified into 10 application types of gabion. The classification types of gabion were mostly related to the erosion and collapse prevention across road cut-slope. Gabion work sites in this study were classified into 30 sites (31%) for below 10% gradient, followed by 31 sites (32%) for 11~30% gradient, 20 sites (21%) for 31~50% gradient, and 16 sites (16%) for 51~80% gradient. Gabion works were constructed mostly in low gradient than in high gradient. 34 gabion sites (35%) among 97 sites were not covered by vegetation and 52 gabion sites (54%) showed vegetation cover rates of 1~30%. On the scenic preference analysis, public groups understood that the scenic view of gabion in cutting slope can be improved by vegetation cover, whereas expert groups prefer to scenic view of gabion only. However, expert groups encouraged subsequently vegetation covering to improve scenic view during gabion works in cutting slope.

• Journal of Navigation and Port Research
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• v.41 no.4
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• pp.195-206
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• 2017

In situ capping technology for marine sediment pollution control has never been applied in South Korea. In this study a pilot project for the capping was carried out in Busan N Harbor. Pipeline and clamshell capping technologies were implemented for the pollution control. Changes of capping shapes, sediment contamination, and the time and costs required for the two constructions were compared. Both the pipeline and clamshell technologies were found to satisfy the target thickness of 50 cm on average. However, the pipeline method did not operate sensitively in terms of change of the sea floor topography, resulting in an uneven shape and a thickness. Organic carbon and ignition loss quite decreased after the pipeline or the clamshell capping while pH showed no significant change. Organic and residual fraction of Cd, Ni, and Zn in the sediments appeared to decrease after all cappings. The pipeline method took a construction time four times as much as the clamshell method. The clamshell method was demonstrated to reduce the construction cost by about 40% compared with the pipeline method. However, a monitoring for all the parameters needs to be conducted at least two years in order to better evaluate an efficiency of the pollution control by these capping constructions.