• Wind and Structures
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• 제8권3호
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• pp.213-233
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• 2005

Wind uplift rating of roofing systems is based on standardized test methods. Roof specimens are placed in an apparatus with a specified table size (length and width) then subjected to the required wind load cycle. Currently, there is no consensus on the table size to be used by these testing protocols in spite of the fact that the table size plays a significant role in wind uplift performance. Part I of this paper presented a study with the objective to investigate the impact of table size on the performance of roofing systems. To achieve this purpose, extensive numerical experiments using the finite element method have been conducted and benchmarked with results obtained from the experimental work. The present contribution is a continuation of the previous research and can be divided into two parts: (1) Undertake additional numerical simulations for wider membranes that were not addressed in the previous works. Due to the advancement in membrane technology, wider membranes are now available in the market and are used in commercial roofing practice as it reduces installation cost and (2) Formulate a logical step to combine and generalize over 400 numerical tests and experiments on various roofing configurations and develop correction factors such that it can be of practical use to determine the wind uplift resistance of roofs.

• Wind and Structures
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• 제4권3호
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• pp.213-226
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• 2001

Wind uplift rating of roofing systems is based on standardised test methods. Roof specimens are placed in an apparatus with specified table size (length and width) then subjected to the required wind load cycle. Currently, there is no consensus on the table size to be used by these testing protocols in spite of the fact that a table size plays a significant role in evaluating the performance. This paper presents a study with the objective to investigate the impact of table size on the performance of roofing systems. To achieve this purpose, extensive numerical experiments using the finite element method have been conducted to investigate the performance of roofing systems subjected to wind uplift pressures. Numerical results were compared with results obtained from experimental work to benchmark the numerical modeling. Required table size and curves for the determinations of appropriate correction factors are suggested. This has been completed for various test configurations with thermoplastic waterproofing membranes. Development of correction factors for assemblies with thermoset and modified bituminous membranes are in progress. Generalization of the correction factors and its usage for wind uplift rating of roofs will be the focus of a future paper.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.247-248
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• 2016

Globally the interest of large-scale structure has been increasing for the use in various social and cultural events. However various problems for building large-scale structure in South Korea are expected in terms of construction method and site management due to the lack of experience. Construction method and planning significantly affects on making decisions. There are only theoretical approach for constructing large-scale building in domestic with the limited experience of constructing constrained size structure. Through Analytic Hierarchy Process with experts, derived decision factors mostly used construction method in construction of large-scale structure. Derived factors from this study will support making decisions for field management in constructing large-scale structure.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.197-198
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• 2017

Large spatial construction needs to consider various construction management factors through the construction guide, including high-tech roofing works for creating large space without columns and erecting large spatial structure. However, the domestic large spatial construction relies on overseas construction technologies due to the lack of construction guide of large spatial construction and experience in similar type of project. To improve the problem, we deduced principal items of construction management considering characteristics of large spatial construction as a preliminary study for developing a construction guide.

• 한국수산과학회지
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• 제20권6호
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• pp.561-567
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• 1987

순환 여과식 양식에 있어서 사육수에 축적되는 암모니아를 여과 재료별로 그 제거 능력을 알아보고, 실제 산업에의 적용에 관한 문제를 검토하였다.. 여과 재료는 첨모직(pile cloth), 스카이 라이트 골판(corrugated skylight roofing plate), 요철 플라스틱판(embossed plastic plate), 및 자갈의 4종류를 사용, $90cm\times60cm\times60cm$(깊이)의 수조에 각각 2개씩 같은 재료를 넣어서 모두 8개를 설치하였다. 주입수는 부산수산대학 순환여과식 양식 시설의 어류사육 탱크에서 나오는 물을 사용하여 그 속에 함유된 암모니아 제거능력을 측정하였다. 정상적 기능을 발휘하는 두 기간의 여과 재료별 1일 $1m^3$의 여과제 설치 용적당 평균 암모니아 제거 능력은 다음과 같았다. 1) 첨모직 8.381g 2) 2) 스카이 라이트 골판 7.834g 3) 요철 플라스틱판 7.797g 4) 자갈 7.051 g 이와 같이 주기능 발휘 기간동안에는 재료별 차이가 별로 없었지만 그 기간의 길이 차이, 청소의 난이도, 설치 비용 등을 고려해야 한다. 특히 대형 여과조의 경우, 자갈 여과조를 청소하는 일은 대단히 어렵고, 첨모직 여과조는 그 설치 작업이 까다롭고, 배수시 그 구조를 유지하는 데 어려운 문제가 따른다. 이러한 관점에서 볼 때 스카이 라이트 곡판과 요철 플라스틱판이 가장 적당하다고 생각된다. 그러나, 실제 설치시는 재료의 입수 가능성, 가격은 물론, 사용중 또는 계획중의 여과 탱크에의 적합 여부도 고려되어야 한다.

• 한국산업보건학회지
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• 제21권4호
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• pp.201-208
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• 2011

Objectives: According to the compliance of the asbestos-related regulation, every building has to be inspected for asbestos presence before its abatement work. This study was performed for identifying the types and contents of asbestos in building bulk samples. Materials and Methods: Bulk samples were collected during the asbestos inspection in 2010. We grouped the bulk samples into the regulated asbestos containing materials(RACM), presumed asbestos containing materials(PACM), and construction products. Additionally, the types of asbestos in all bulk samples were identified by polarization microscopy(PLM). Results: The RACMs were from building, house, pipe and facility. The RACMs were found mainly building (72.1%) and house (93.7%). The contents of chrysotile in building, house and facility were 66.9% (1-90%), 89.7% (2-90%) and 11.0% (2-90%), respectively. PACMs were surfacing material, thermal system insulation (TSI), and miscellaneous material. The miscellaneous materials that showed a high detection rate (79.2%) were ceiling, roofing and wall materials. Among them, the roofing materials had high chrysotile content(9.7%, 2-21%), followed by wall (8.7%, 2-21%) and ceiling (3.4%, 1-17%). In the construction products, asbestos was found mainly in slate (92.6%, 2-21%), including chrysotile. The slate had high asbestos content (9.7%, 2-21%), followed by cement flat board (8.7%, 2-19%) and textile (3.4%, 1-17%) Conclusions: Utilizing these results, it would be contributed to construct a useful ACM database and prevent from asbestos exposure to workers in the asbestos abatement and maintenance works.

• Structural Engineering and Mechanics
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• 제61권2호
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• pp.255-266
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• 2017

In this study, self-supporting roofing elements especially convenient for large-span structures such as stadium, airport terminal, mall, coliseum, etc. were examined with respect to critical buckling load. These elements were assumed as laminated composite plates and, variation of free-edge forms, cutout types and lamination configurations were used as design parameters. Based on the architectural feature and structural requirements, the effects of curvilinear free-edge form on critical buckling load were focused on in this research. Within this scope, 14 types of lamination configuration were specified according to various orientation angle, number and thickness of plies with a constant value of total plate thickness. Besides that, 6 different types of cutout and 3 different free-edge forms were determined. By combining all these parameters 294 different critical buckling load analyses were performed by using ANSYS Mechanical software based on finite element method. Effects of those parameters on critical buckling load were evaluated referring to the obtained results. According to the results presented here, it may be concluded that lamination conditions have more significant influence on the critical buckling load values than the other parameters. On the other hand, it is perceived that curvilinear free-edge forms explicitly undergo changings depending on lamination conditions. For future work, existence of delamination might be considered and progression of the defect could be investigated by using non-linear analysis.

• 한국염색가공학회지
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• 제26권2호
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• pp.106-113
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• 2014

Work-related falls are a major problem in the construction and roofing industries. To avoid serious injury to the worker caused by high decelerations or forces, different systems to absorb the energy of a fall are implemented in personal protective equipment. In this study, shock energy absorber lanyard protection tube was prepared using high tenacity PET fiber, P-aramid fiber, and UHMWPE fiber, respectively. Dynamic load test and static load test, bursting strength test based on the Korea fall protection equipment standard(Korea Occupational Safety & Health Agency standard 2013-13) or conformity European safety test(CE : EN355) were conducted. Especially maximum arrest force by dynamic load test of energy absorber showed below 6,000N.

• 한국주거학회논문집
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• 제12권3호
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• pp.41-49
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• 2001

This study attempts to present a new interpretation of the Jeju province Waga, authorized as Jeju province Folklore, in the context of lifestyles of residents distinctive in the Jungji, Chatbang, and Gopang system. Study results uncovered that (1) only one Jungji, a traditional house kitchen, exists in one house boundary, in the form of detached building in the 4 units of Gaok (K-2 Gaok, K-3 Gaok, C-1 Gaok, and C-2 Gaok) (2) Chatbang had multifaced-functions; as a place for diet for mistress and children, a place for preparing meals for a mister who diet in the room, and as an auxiliary meal-preparation facility in time of domestic celebration day. (3) Gopang was mostly a place for grain storage, and K-3 Gaok has one unit, K-1 Gaok, C-1 Gaok, and C-2 Gaok had 2 units, and K-2 Gaok and H Gaok had 3 untis of Gopang. (4) Jungji and Chatbang were correlated for meal preparation and diet while activity-line of flow was divided each other. (5) Jungji and Gopang were located at the opposite edges of of each house, revealing no consideration of indoor activities. (6) The ratios of space of Jungji, Chatbang and Gopang out of the whole house space were, average 23% in the case of Jungji located in the inner house, and average 37% in the case of Jingji located in the detached building, average 14% larger in the case of detached Jungji system.

• 한국실내디자인학회논문집
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• 제16권6호
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• pp.36-46
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• 2007

Regeneration of old buildings is one of the most imperative responses to the 21th century issue of sustainable urban architectural environment. In particular, creative circulation of generation which conversion means highlights the conversion as a new design method. In this study, by examining buildings built over the last decade, the mutual relationship between old elements of existing buildings and new elements of newly required functions was analyzed and types of relationships such as 'alien insertion', 'mediate intervention', 'endogenous expansional enveloping', 'contrastive confliction' and 'over-layering' were defined. In addition, design strategies including the paradoxical curio, fore-grounding and unification were derived from each relationship. Finally, according to the relation type and design strategy, this study suggests several features of conversion design; (1) maximization of symbolism using unfamiliarities - emphasizing futuristic or contextual symbol with intentional contrasts by preserving the work or using contemporary addition; (2) time confusion using neutral space - meeting the need by harmonizing and cooperating existing elements and new elements; (3) mutual emphasizing by individualization - revealing differences between old and new for an aesthetical tension; (4) synchronism by constructional combination - making the one unity of different layers; (5) expansion by enveloping - experience of visual reverse and creation of extra space by roofing above building groups. The reconversion should be continuously researched in the future since conversion is a sustainable design method for the future of architecture.