校園雨水再利用貯量設計模式之研究 -以台北市國小為對象-

A Study on the Storage and Reuse of Rainwater: Taipei's Elementary Schools for Example

翁彩瓊(Tsai-Chung Wung)

指導教授 ： 黃世孟

國立臺灣大學/工學院/土木工程學研究所/博士(2006年)

https://doi.org/10.6342/NTU.2006.00421

摘要

目前綠建築標章中水資源之替代性已成為建築技術規則中重要的一環，利用雨水收集經過簡易過濾成為不與身體接觸之用水，是新建築採行最普遍之方式，然其現況卻呈現利用上極大差異性與不適性，現有基準所依據之分類向度過於簡化。因此，本研究以台北市國小為對象，探討專有建築類型設置雨水貯集沖廁利用之合理性與可行性，研究以既有校園為基礎，嘗試提出適用於國小校園之雨水沖廁貯留系統，以期規模之確立提供具有合理化之貯量標準。
本研究內容著重在實務應用上，以台北市降雨探討為起始，利用氣象局設置之十五處雨量站，探討台北市地形變化之降雨影響，依雨量分佈特性、季節變化、降雨機率等影響因素區分為四大區七小區，以校園距離對應測站關係修正地點降雨量，研究呈現台北市地形變化對降雨之影響性，確實不應以單一雨量站為降雨基礎作為貯量設計之利用。
經由實際調查校園可供集雨之類型與面積，確立校園集雨以屋頂為優先考量，次為操場硬質跑道，配合降雨制定校園集雨量，研究結果顯示校園屋頂集雨面積集中於20%左右，集雨量受降雨條件影響最高雨量集中於九月；單以屋頂面積探討氣象站校園均值比較發現，降雨極值差異近20倍，單一氣象站中極值差異最高近7倍，加上操場集雨後，氣象站平均值則有7倍差異；研究說明同分區測站之倍數差異影響因子除校園位置外，更受集雨面積影響，而單一測站之校園差異，則受月份降雨是否均度影響。經因子分析探討校園用水發現人口數影響最鉅，研究配合教育策略，制定人數之需雨補充量關係性。供需關係顯示增加操場集雨，可使全年12個月供需替代比均為100%之校園自3所增至8所。
研究以既有校園集群分化方式，依校園供需替代率制定時點利用特性，並以最低替代率月份提供新設校園之比對依據，結果顯示以屋頂集雨設計，集群控制最低點為石牌氣象站一月供需比之13%，而加入操場跑道集雨後，控制最低點為天母氣象站之25%，此二處均為低雨量之A-1區，數值顯示降雨量差異確實具有影響性。
研究貯量之設計以提供七個月實際利用為基礎，但針對替代率過低之校園提供六個月之比對機制，經研究證實許多校園以六個月或七個月滿足性利用率貯量差異性不大，但可因容量增加制定值(100M3)時，將可使初期費用減低而使回收期縮短，更使整體效能增加；研究說明合理性貯量設計，可比對實際並設計過程之需求差異予以更動，亦可依初期設備費用回收狀態評估；研究最終探討現況校園設置問題與設施建議，提供既有與新設校園無論整體建置或單一建設均適合利用之雨水貯留具體參酌體系。

關鍵字

國小校園 ； 替代率 ； 雨水貯留 ； 氣象站 ； 群集分析

並列摘要

Currently in green building labels, the replace ability of water resources has become an important link in building techniques and rules. Rainwater collected undergoing simple filtering to become water without coming in contact with the human body is the most common way adopted by new buildings. The status quo, however, presents a great discrepancy and is unsuitability inasmuch use is concerned, in that the taxonomy which the current criterion relies upon is too simplistic. For this reason, this study aims at Taipei's elementary schools by exploring the rationality and feasibility of the use of rainwater storage for flushing toilets in dedicated building types. Based upon existing campuses, the present work attempts to propose rainwater storage and flushing system suitable for elementary school.
This study lays emphasis on practical applications. Starting with Taipei's rainfall using 15 weather stations, it discusses the influence of variations in Taipei's topography on rainfall. By characteristics of rainfall distribution, seasonal change, probability of precipitation, Taipei is divided into four areas and seven sub-areas. Rainfall of locations is corrected based upon the distance between campus and measuring stations. The result shows that according to the influence of Taipei's topography on precipitation, it is indeed improper to base rainfall storage design on a single rainfall station alone.

After surveying types and areas available for collecting rainwater on the campuses, it is found that campuses collect rainwater by prioritizing roofs, followed by the hard tracks of playgrounds. In respect to rainwater collection, the result indicates that campus roof rainwater collection is concentrated in approximately 20% of the area, and that the highest collection is concentrated in September due to precipitation conditions. According to the campuses' means from weather stations in terms of roof areas alone, differences in extreme values of rainfall are close to 20 times. Extreme values at one single weather station are nearly 7 times at maximum. If collection of playgrounds is included, there is a difference of 7 times in weather stations' means. The result shows that factors that affect the difference of times at weather stations in the same areas include collection areas, in addition to the campus position. Differences between campuses at one single weather station are affected by the factor of whether monthly rainfall is even. According to an analysis on water use on campuses, the population is the factor that has the biggest influence. The study has formulated a relation between population and rainfall supply needed. The supply-demand relation indicates that by raising the collection of playgrounds, the number of campuses with a supply-demand replacement ratio at 100% all year round can increase from 3 to 8.
The study clustered the campuses, set up reference time-points against supply-demand replacement ratios, and compared with newly built campuses using the lowest replacement ratios. The result indicates that using roof rainfall collection design, the lowest point of clustering control is Shipai Weather Station's supply-demand ratio of 13% in January. If rainfall collection of playground tracks is included, the lowest point is Tianmu Weather Station at 25%. These two areas are in the low-rainfall A-1 area. Data that show differences in rainfall constitute an influence.
The study attempted a rational storage for seven months of actual use, but provided instead a 6-month comparison mechanism for campuses with an overly low replacement ratio. The result shows that for a number of campuses, there was little difference in storage use rates in six months or seven months. But when set values for capacity were increased (100 M3), the initial cost could be reduced to shorten the period of return on investment (ROI), and the overall efficiency could be enhanced.
Comparing the difference between actual conditions and design can change a rational storage design. Moreover, evaluation can be made according to the ROI of initial equipment costs. Finally, the study discusses the current establishment problems and makes suggestions on facilities in order to propose a rainwater storage system to serve as a reference for existing and new campuses in single construction or in overall establishment.

並列關鍵字

elementary schools ； replacement ratios ； rainwater storage ； weather stations ； cluster analyze

參考文獻

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