• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
• /
• pp.337-338
• /
• 2018

In recent years, residential apartment building parking lots are built in underground spaces, and with conjunction to improve the environment of the urban area, artificial greeen roof systems are installed on the upper slabs. However, early plant growth are resulting in root penetration into concrete cracks and in turn into the waterproofing membranes, leading to degradation and damaging of the waterproofing system and structural durability. This issue highlights a problem of conventional maintenance system of concrete structures, and proposals for amendments follow. In this study, a waterproofing and root barrier construction design for the upper slabs of residential building underground parking lots is proposed, and motioned to be added into future construction specifications.

• 환경생물
• /
• 제36권3호
• /
• pp.319-328
• /
• 2018

The morphology, anatomy and reproduction (tetra/bisporic and male) of Lithothamnion japonicum Foslie was studied, using holotype material and materials collected from Korea. Lithothamnion japonicum is characterized based on the presence of encrusting, warty to fruticose thallus, branched or unbranched short and cylindrical protuberances, conical shaped spermatangial conceptacles, branched (dendroid) spermatangial systems formed on floor, walls, and roof of conceptacle chamber, cylindrical shaped spermatangial conceptacle canal, 9-10 cell layered spermatangial conceptacle roof, raised tetra/bisporangial conceptacles without rims, flattened tetra/bisporangial conceptacle pore plate, 16-50 pores on each pore plate, 6-8 rosette cells surrounded by each pore, pore canal lining filaments composed of tetra/bisporangial conceptacle roof, and buried senescent tetra/bisporangial conceptacles completely infilled with relatively large and irregularly arranged calcified sterile cells. In this study, we report a new record of Lithothamnion japonicum from Korean coasts.

• 한국건축시공학회지
• /
• 제11권6호
• /
• pp.634-644
• /
• 2011

Recently, As a part of urban forestation, the introductions of green roofs into public projects has been actively driven. Supported by this policy, the sizes of domestic green roof related markets have been rapidly expanding and many types of root barrier materials developed in Korea or abroad are being commercially distributed. In this study, root barrier tests were conducted over two years with nine types of sheet type waterproof materials that are the most commonly used as root barrier layers in green roof systems. The test conditions prepared considered the climates, natural features and vegetation in Korea and the results and related root barrier performance were verified. From the results of this study, the necessity to improve the joint part of root barrier sheets and forming methods has been identified and a measure to improve domestic root barrier testing methods was proposed.

• Computers and Concrete
• /
• 제31권5호
• /
• pp.371-384
• /
• 2023

Precast roofing systems employing prestressed elements often serve as smart structural solutions for the construction of industrial buildings. The precast concrete elements usually employed are highly engineered, and often consist in thin-walled members, characterised by a complex behaviour in fire. The present study was carried out after a fire event damaged a precast industrial building made with prestressed beam and roof elements, and non-prestressed curved barrel vault elements interposed in between the spaced roof elements. As a consequence of the exposure to the fire, the main elements were found standing, although some locally damaged and distorted, and the local collapse of few curved barrel vault elements was observed in one edge row only. In order to understand and interpret the observed structural performance of the roof system under fire, a full fire safety engineering process was carried out according to the following steps: (a) realistic temperature-time curves acting on the structural elements were simulated through computational fluid dynamics, (b) temperature distribution within the concrete elements was obtained with non-linear thermal analysis in variable regime, (c) strength and deformation of the concrete elements were checked with non-linear thermal-mechanical analysis. The analysis of the results allowed to identify the causes of the local collapses occurred, attributable to the distortion caused by temperature to the elements causing loss of support in early fire stage rather than to the material strength reduction due to the progressive exposure of the elements to fire. Finally, practical hints are provided to avoid such a phenomenon to occur when designing similar structures.

• 한국환경복원기술학회지
• /
• 제15권2호
• /
• pp.137-147
• /
• 2012

GRS is an effective urban ecology restoration technique that can manage a variety of environmental functions such as ecological restoration, rainwater spill control and island heat effect from a low-impact development standpoint that can be utilized in new construction and retrofits. Recently, quantitative evaluation studies, both domestic and abroad, in the areas related to these functions, including near-earth surface climate phenomenon, heavy rainwater regulation, thermal environment of buildings, have been actively underway, and there is a trend to standardize in the form of technological standards. In particular, centered on the advanced European countries, studies of standardizing the specific insulation capability of buildings with green system that comprehensively includes the green roof, from the perspective of replacing the exterior materials of existing buildings, are in progress. The limitation of related studies in the difficulties associated with deriving results that reflect material characteristics of continuously evolving systems due in part to not having sufficiently considered the main components of green system, mechanisms of vegetation, soils. This study attempts to derive, through EnergyPlus, the effects that the vegetation-related indicators such as vegetation height, FCV, etc. have on building energy load, by interpreting vegetation and soil mechanisms through plant canopy model and using an ecological standard indicator LAI that represent the condition of plant growth. Through this, the interpretations that assume green roof system as simple heat insulation will be complemented and a more practical building energy performance evaluation method that reflects numerical methods for heat fluxes phenomena that occur between ecology restoration systems comprised of plants and soil and the ambient space.

• 한국조경학회지
• /
• 제41권5호
• /
• pp.1-8
• /
• 2013

이 연구는 2종의 저관리 경량형 옥상녹화시스템(세덤박스와 우수저장형 옥상녹화시스템)을 대상으로 옥상녹화 효과를 평가하기 위해 옥상의 건조한 조건에 잘 견딜 수 있는 내건성 식물 12종을 대상으로 실험을 실시하였다. 실험은 우수저장형 옥상녹화시스템의 기초 연구를 위해 식물의 내건성을 평가하였다. 식물의 내건성 평가를 위해 무관리 조건에서 12종 식물의 건조스트레스의 저항성을 평가하였다. 내건성 평가는 처리 시간에 따라 12종 식물의 상대수분함량의 변화, 전해질 용출 평가, 엽록소 함량의 변화, 토양수분과 건조 스트레스와의 관계를 연구하였다. 건조처리 시간이 길수록 식물들의 상대수분 함량과 엽록소 함량이 감소하면서, 전해질 용출이 증가하였다. 따라서 식물의 내건성 평가 결과, Pulsatilla koreana, Ainsliaea acerifolia를 제외한 10종이 내성이 강하여 옥상녹화에 적용 가능한 종으로 판단되며, 우수저장형 옥상녹화 시스템에서 식물들의 내건성은 식생박스의 식물들보다는 강한 것으로 나타났다. 따라서 우수저장형 옥상녹화 시스템이 식물의 생육과 건조조건에 대한 저항성 증진 효과가 있는 것이 증명되어 도시 옥상녹화에 이용할 수 있다.

• 생물환경조절학회지
• /
• 제25권4호
• /
• pp.334-342
• /
• 2016

지붕 환기장치 설치방법의 개선에 의한 작물 재배효과를 검증하고자 농가현장에서 개선 지붕 환기방식과 관행환기방식을 비교, 분석하였다. 개선 지붕 환기방식은 참외재배 단동 플라스틱 온실(폭 5.6m, 길이 108m, 측고 1.1m, 동고 2.2m)에 지붕 환기팬(용량 $38m^3/min$)과 환기통(지름 60cm)을 각각 15m와 6m 간격으로 설치하였고, 대조구로서 관행 지붕 환기방식은 각각 20m와 8m 간격으로 설치하였다. 관행 및 개선 지붕 환기 방식에 따른 생육을 조사한 결과, 관행 환기통과 환기팬 처리에 비해 개선 환기통과 개선 환기팬 처리에서 경경, 엽장, 엽병장, 및 엽폭의 값이 낮게 나타나는 경향을 보였다. 생육기 전반부에 관행 환기통 처리는 환기팬 처리에 비해 절간장이 다소 길게 발달하였는데 이는 착과수가 환기팬 처리에 비해 적었고, 착과수 감소로 인해 동화산물이 잎과 줄기의 신장부로 좀 더 이동된 영향으로 판단되었다. 참외재배 단동 비닐하우스에서 과실 수량을 조사한 결과, 개선 환기팬과 개선 환기통 처리는 관행처리에 비해 과중은 약간 작았지만, 착과수 증가로 인해 전체 수량은 높게 나타났다. 개선 환기팬과 개선 환기통 설치 하우스에서는 관행 지붕 환기 하우스에 비해 상품과율이 높았으며, 10a당 상품수량도 각각 8,391kg, 7,283kg 으로 나타나 관행 지붕 환기에 비해 개선 환기팬 처리는 661kg, 개선 환기통 처리는 487kg 더 증가하였다. 개선 환기팬 처리는 고온기에 암꽃수와 착과수가 가장 많았고, 낙과수는 가장 낮게 나타났으며, 관행의 환기통 처리에 비해 과실의 크기는 작았다. 시기별 환기방식에 따른 참외 과실의 품질을 조사한 결과, 관행 환기통 환기에서 과중, 과경, 과폭, 및 과육두께가 가장 높게 나타났으나, 과폭, 과육두께에 있어서 통계적인 유의차는 나타나지 않았다.

• 대한기계학회논문집A
• /
• 제38권10호
• /
• pp.1093-1100
• /
• 2014

본 논문의 목적은 알루미늄 압출재와 샌드위치 복합재를 사용한 초고속 자기부상 열차의 하이브리드 차체 경량화 설계를 제안하는 것이다. 샌드위치 복합재는 무게 감소를 위해 2차 부재인 루프에 적용되었다. 용접에 의한 샌드위치 복합재 루프와 알루미늄 압출재 사이드 프레임과 접합시키기 위해 샌드위치 복합재 네 옆면에 가이드 알루미늄 프레임을 갖도록 고안하였다. 가이드 알루미늄 프레임의 체결력은 3점 굽힘 시험을 통해 검증하였으며, 차체의 구조 안전성 및 충돌 안전도는 상용 유한요소해석프로그램을 이용하여 철도안전법에 따라 평가하고 검증하였다. 연구결과, 알루미늄 압출재와 샌드위치 복합재로 이루어진 하이브리드 차체는 알루미늄 압출재로만 이루어진 차체에 비해 무게 절감 효과와 향상된 구조 성능을 얻을 수 있다.

• 한국환경복원기술학회지
• /
• 제7권1호
• /
• pp.1-9
• /
• 2004

Caused on the excessive heat accumulation of concrete material, the indoor thermal environment of reinforced concrete building is so bad in Okinawa. As the interruption of solar radiation could be one of the methods to improve it, the purpose of this study is to find out the effect of adopting solar radiation interrupting materials -Solar insulating block, Grass, and both of them- for the improvement of thermal environment. As the result, it was found that grass on the solar insulating block which has an air layer obviously improved the indoor thermal environment of RC building which was applied to. And it was found that the systems have an effectuality on heat island phenomenon simultaneously. It could be proposed as a good system which improve the indoor thermal environment of the existent houses.

• 한국공간구조학회지
• /
• 제16권1호
• /
• pp.13-17
• /
• 2016