|Abstract: ||摘要:由於都市化現象造成人口快速密集成長，因不透水面積密度增加，使得洪澇問題隨之上升，透過適當的管理進行雨洪消減及增強環境綠化則為當前之要務。礙於都市地價昂貴，難以興建大型綠地，因此屋頂綠化成為解決都市化問題的替代方案之一。屋頂綠化具有的效益包括增加保水性、降低雨洪發生之可能性、減少都市熱島效應及綠美化都市。近年來歐美國家大力推動此綠化方法，台灣目前集度缺乏屋頂綠化本土相關之研究，因此如何將屋頂綠化之效益本土化及量化，並結合屋頂雨水貯集再利用，以解決屋頂綠化所需水源的問題，成為本研究之重點目標。 本研究擬彙整分析國內外有關屋頂綠化水文水理之研究，並建立屋頂綠化相關試驗，探討各項水文機制，進而建構「屋頂綠化通用降雨逕流模式」。研究不同試驗配置之屋頂綠化逕流量、蒸發散量及CN值等影響，並評估其對都市雨洪消減效益，最後結合雨水貯集再利用系統容量設計模型，並評估其成效。 計畫擬以二年度來進行，第一年（99.08-100.07）為彙整相關國內外屋頂綠化相關工程水文水理文獻，建構屋頂綠化降雨逕流試驗系統及屋頂綠化蒸發散試驗系統，進行試驗及成果分析，初步建構屋頂綠化通用降雨逕流模式；第二年（100.08-101.07）為考慮不同配置(介質種類、介質厚度、植栽種類及傾斜角度等)之降雨逕流及蒸發散試驗並進行試驗成果分析，修正通用降雨逕流模式、建構電腦操作介面，並建構單一建築物屋頂綠化CN值變化圖，進而評估區域尺度屋頂綠化對都市雨洪消減效益，並建立屋頂綠化與雨水貯集再利用系統容量設計模型。|
abstract:Due to urban development, population increase and enlargement of imperious areas, urban flood and drought occurs increasingly. Therefore, with proper management and enlargement the area of green land to mitigate urban flood will be treated as the first priority task. Setting up the large green land area is difficult due to high land cost in urban areas. Hence, greenroof becomes an alternative for increasing the green land. Greenroof has the benefits of reducing urban flood and heat island effects, increasing water retention capacity, increasing urban beauty, etc. Therefore, greenroof is becoming more common in many parts of Europe and North American countries because of the high land cost and density of population in urban areas. There is limited research report in domestic relative to greenroof in reducing urban flood. The main purpose of this research is to develop the technologies to quantify the benefits of greenroof in urban flood mitigation, etc. and a mathematical model which combines the greenroof and rainwater harvest system to reduce water supply from city water. This project will collect and analysis the research results related to hydrology and hydraulic performance of greenroof from domestic and foreign countries. In the research, a physical model for greenroof will be build to experimental study the hydrological behavior of greenroof which includes runoff, evaporation, CN value, etc. Based the experimental results and hydrologic theory, a general model of rainfall-runoff for greenroof will be developed. This model will further be used to evaluate the effectiveness of urban flood mitigation for different space scale installing greenroof. Also, in the study, a mathematical model for estimating the storage volume requirement for rooftop rainwater harvest system combine with greenroof will be developed. It takes two years to complete. In the first year (99.08-100.07), literature review is required focusing in the area of hydrology and hydraulic behavior of greenroof. Two physical models for rainfall-runoff and evaporation will be set up. Indoor and outdoor experiment will be carried out. With the experimental results and developed theory, a general model of rainfall-runoff for greenroof will be developed. In the second year (100.08-101.07), rainfall-runoff and evaporation experiments will be continued but with different growing medium, thickness of growing medium, plants used, slope, etc. These results will be used to modify the general model of rainfall-runoff for greenroof obtained in the first year. Furthermore, a user friendly computer model will be developed. Also, a CN value chart will be obtained for a single building with greenroof. The rainfall-runoff model and CN value will be used effectively and quantitatively to assess the effectiveness of urban flood mitigation due to establishment of greenroof for different space scale (etc. community, school, urban area). Finally, a mathematical model for estimating the storage volume requirement for rooftop rainwater harvesting system combine with greenroof will be developed.