• KIEAE Journal
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• 제13권5호
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• pp.89-96
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• 2013

Green roofs can reduce surface water runoff, provide a habitat for wildlife moderate the urban heat island effect, improve building insulation and energy efficiency, improve the air quality, create aesthetic and amenity value, and preserve the roof's waterproofing. Green roofs are mainly divided into three types : intensive, simple-intensive, and extensive. Especially, extensive roof environment is a harsh one for plant growth; limited water availability, wide temperature fluctuations, high exposure to wind and solar radiation create highly stressed environment. This study, aimed at extensive green roof, was carried out on the rooftop of the library at Seoul Women's Univ. from October to November, 2012 and from March to August, 2013. To suggest the most effective vegetation model for biodiversity and heat island mitigation, surface temperatures were monitored by each vegetation model. We found that herbaceous plants of Aster sphathulifolius, Aceriphyllum rossii and Belamcanda chinensis, shrub of Syringa patula 'Miss Kim', Thymus quinquecostatus var. japonica, Sedum species can mixing each other. Among them, the vegetation models including Sedum takesimense, Aster sphathulifolius, Thymus quinquecostatus var. japonica was more effective on the surface temperature mitigation, because the species have the tolerance and high ratio of covering, and also in water. Especially, in the treatment of bark mulching, they helped to increase the temperature of vegetation models. In the case of summer, temperature mitigation of vegetation models were no significant difference among vegetation types. Compared to surface temperature of June, July and August were apparent impact of temperature mitigation, it shows that temperature mitigation are strongly influenced by substrate water content.

• Earthquakes and Structures
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• 제11권2호
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• pp.265-280
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• 2016

Environmental and operational benefits of green roofs are manifolds; however, their main disadvantages are cost and weight. New technology enabled the use of plastics to reduce the weight of green roof systems to promote their installation. To maximize their potential benefits, green roofs can be installed on existing structures. This study evaluates the influence of green roofs on the seismic response of 3, 6, and 8 storey reinforced concrete ductile moment resisting frames, which were designed according to current seismic standards, however, not designed for green roofs. For each frame, three different types of roofs are considered: gravel flat roof, extensive green roof, and intensive green roof. Nonlinear dynamic time history analysis using an ensemble of twenty real earthquake records was performed to determine the inter-storey drift demand and roof drift demand for each frame. Eigenvalue analysis was also performed to determine the impact of green roofs weight on the elastic and cracked periods of the structure. Results from the analysis demonstrated that intensive and extensive green roofs do not affect the seismic performance of reinforced concrete frame structures.

• KIEAE Journal
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• 제13권3호
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• pp.105-110
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• 2013

Green roof system is classified as intensive greening, extensive greening or mix of intensive-extensive greening. Recently, light-weigh green roof has been performed actively, because buildings have been considered loads, design and maintenance. This study was conducted to design soil depth for light-vegetation block with using bottom-ash. As a result, it was found that growth of plant had no direct effect on soil depth even it was less than 10cm. Soil depth having under 5cm could be integration of plant roots and vegetation blocks. It was also possible to grow organic vegetables through the experiment of planting. According to this experiment, as light-vegetation block with bottom-ash was used for planting, it makes design shallow soil depth. The results will help install green roof system conveniently not only new buildings but also used buildings.

• 토지주택연구
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• 제7권4호
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• pp.299-305
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• 2016

본 연구는 기후변화 대응을 위한 계획적 수단으로서 옥상녹화에 따른 건축물 에너지 저감효과를 분석하여 옥상녹화 적용확대를 위한 기초자료를 제시하는데 목적이 있다. 대상지는 최근 준공된 공동주택 중 옥상녹화가 적용된 주동과 부대복리시설을 선정하였다. 건축 유형에 따라 경량형(토심 20cm) 및 혼합형(토심 40cm) 옥상녹화를 적용하고, 디자인 빌더(Design Builder)를 활용하여 옥상녹화 적용에 따른 에너지 저감량을 비교 분석하였다. 분석결과, 모든 대상 건축물에서 옥상녹화 적용시 에너지 저감효과가 있으며, 혼합형 옥상녹화가 경량형 옥상녹화에 비해 냉 난방 에너지 저감효과가 더 큰 것으로 나타났다.

• KIEAE Journal
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• 제11권1호
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• pp.21-28
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• 2011

The objective of this study is to analysis the properties for reclassifying green roofs into three types by cluster analysis after investigating the present condition in thirty green roofs which were created from 2002 to 2004 by Seoul Metropolitan Government. The previous classification was resulted in structure safety diagnosis in the type of green roofs and visible judgment by experts in sites. However, it should have been corrected. Therefore, it needed a reestablished concept and a reclassification in green roofs. The results of this study are as follows : the concept of a rooftop garden and a green roof is different from previous studies. The rooftop gardens named by intensive green roofs are closed to integrated management, whereas the green roofs are closed to low management. The reclassification of green type was also conducted to use the statistic analysis of categorical regression by previous studies, and the factors extracted by the categorical regression were influenced by greening type. The figure of R-square representing explanation in regression analysis is 95.2%. As this result was analyzed, it was proved into rooftop gardens demanded for high activity by people.

• 한국환경복원기술학회지
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• 제11권6호
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• pp.143-152
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• 2008

A comparative analysis of rooftop greening in Korea and Japan was carried out to understand current status of rooftop greening creation and technology and to give directions to frame a policy or plan on rooftop greening in Korea. Besides literature studies, questionnaire survey to Korean and Japanese experts on rooftop greening were done. As results, the annual creation areas, the types and the scales of rooftop greening in Seoul and Tokyo until 2007 were analysed and the satisfaction on the creation areas and technologies, the preference types, the present levels of and the most important parts among policies (support systems), technologies (creation methods), materials, maintenances and user programs for the development or expansion of rooftop greening in Korea and Japan were compared. The creation areas of rooftop greening in Seoul until 2007 was around 15% in Tokyo but the increasing rate of those in Seoul was faster than in Tokyo. Korean needs for the improvement on the rooftop greening systems and technologies were higher than Japanese, but both desired the expansion of rooftop greening areas in both countries. Korean preferred semi-intensive rooftop greening system but Japanese preferred intensive system. Korean and Japanese rooftop greening experts preferred policies (support systems) and technologies (creation methods) for the most important part for the development or expansion of rooftop greening in both countries.