滲透排水管之入滲效益評估

The Evaluation on The Infiltration Efficiency of Infiltration Pipes

陳順傑(Shun-Chien chen)

指導教授 ： 鄭光炎

國立臺北科技大學/工程學院/土木與防災研究所/碩士(2006年)

摘要

世界各國近年來工商業發展迅速，由於高都市化所導致不透水表面積高增，降低地表之雨水入滲量；而一般都市排水系統其處理方式將雨水集中末端排放，使逕流迅速導入至鄰近河川，無形中增加下游之洪峰流量與逕流面積，每逢豪大雨都市洪氾頻傳。
有鑒於水患所造成生命財產之損失，國外藉由雨水貯集及入滲設施之分散配置來降低地表逕流與達到雨水再利用之功效，其中排水設計方面則採用減少通水量或蓄水能力，因而有貯留池、滲透管溝等之設置。然而我國對於貯留池與滲透側溝此兩項已有相關之研究分析，對於滲透排水管之技術尚屬於理論假設層次。緣此，本研究將探討滲透排水管於沈泥質砂土中之水分變化，與觀測其排水、入滲之情形，另外於上游供水處採取不同水位高度，以瞭解滲透排水管滿管狀態時，水位高差與入滲排放之關係。
研究成果顯示，滲透排水管持續供水狀態時，約可降低28%之上游入流量，且發現有深層滲漏之現象，每分鐘約有1.12%水分以提供地下水之補助量；.於滲透排水管內無水狀態時，土壤水分可保留約20個小時後方下降之情形。而水位高差方面，因水位愈高而導致土壤之入滲與達飽和時間也相對加快。

關鍵字

入滲設施 ； 滲透排水管 ； 地表逕流 ； 入滲

並列摘要

Rapid industrial developments across the world in recent years have resulted in an expanded urbanization. This has been creasing impermeable surface areas which reduce the amount of rain infiltrates into soil. The surface runoff is thus accumulated in the city and commonly drained into nearby rivers through the drainage systems; this is often the cause of high peak flow at downstream and large runoff areas. As a result of that, floods happen frequently after heavy rain falls.
To reduce the lost of life and properties caused by floods, various countries have employed rain detention and infiltration methods to diverse surface runoff and to re-use rain water. Among these methods, detention tanks and infiltration trenches are drainage facilities designed to decrease water flow or detention capacity. Relevant researches and analysis focused on the detention tanks and lateral infiltration pipe can be found in Taiwan; however, the applications of infiltration pipes are still in theories and assumptions. Therefore, this study investigated the water quantity changed in the infiltration pipes installed in silty sand as well as observed their capacities of draining and infiltrating. Furthermore, the elevation of water source located upstream was varied in order to investigate potential correlations between upstream water level and draining capacities when the pipes were full.
The results of this study obtained were: 1) a 28% reduce on upstream inflow when continuingly draining water through infiltration pipes; 2) approximately 1.12 % per minute of the water percolated into groundwater; 3) soil saturation was only reduced 20 hours after stopping providing water from upstream. Additionally, it was found that soil infiltration and saturation rates were increased with higher water level at upstream.

並列關鍵字

infiltration devices ； infiltration pipes ； surface runoff ； infiltration

參考文獻

[1] Harald Sommer(2005), Strategies and tools for a flexible urban stormwater management.

[2] Harald Sommer(2005), Stormwater water source control measures in urban drainage.

[8] T.-C. Jim Yeh(1992), A Numerical Model for Water Flow and Chemical Transport in Variably Saturated Porous Media.

[10] Warren Bell(1999), Storm Water Technology Fact Sheet Infiltration Trench, United States Environmental Protection Agency.

[21] 林憲德、李德河（1998），基地保水性能之研究，內政部建築研究所，台北。