土工膨潤土布阻水特性之研究

The Study of the Hydraulic Barrier Property in Geosynthetic Clay Liners

林謙吉(Chien-Chi Lin)

指導教授 ： 張達德

中原大學/工學院/土木工程研究所/碩士(2002年)

https://doi.org/10.6840/cycu200200426

摘要

土工膨潤土布（Geosynthetic Clay Liner,GCL），又稱皂土布，為近年來新發展出之地工合成材，一般工程界常利用其特殊性質來減少液體滲流通過，以達到防滲阻水（Hydraulic Barrier）的目的。膨潤土布目前在歐美地區漸漸被推廣並使用於各種工程，如渠道、池塘、蓄水池、垃圾掩埋場等，而其中以垃圾及廢棄物掩埋場之應用，最為重要。為了阻隔因垃圾及廢棄物堆積所產生之有毒污染廢液，使其無法滲入天然土層，污染環境，廢棄物掩埋場皆設有阻水層於襯墊系統內，而膨潤土布則是眾多阻水層材料中的效果最為優越的一種。
本研究為了解膨潤土布應用在現地阻水層時防滲阻水之功效，故針對組成膨潤土布的三大構件：地工織物（Geotextile）、膨潤土（Bentonite）、膨潤土布（GCL）本身，以及使用三種不同地區之膨潤土礦所製成的膨潤土布來進行多項定性測試與特性試驗；再者，為了解現地乾濕循環現象（Wet-Dry Cycling）對膨潤土布整體阻水特性之影響，規劃加入此環境條件於相關試驗中來進行模擬。
根據研究結果歸納得知，膨潤土布會因乾濕循環之作用而使其整體之阻水效能降低。由於乾濕循環作用伴隨著水流的衝擊，使得膨潤土布內的膨潤土流失、損耗，甚至產生裂縫，進而使膨潤土布喪失其防滲阻水之功能。
在膨潤土布的乾濕循環滲透過程中，膨潤土布的滲透性大小與穩定性之相關性不大；防滲阻水性質較良好的膨潤土並不一定會有穩定的工程性與耐久性；反之，阻水性不佳之膨潤土布可能因地工織物與製造方法互相之配合性，而有較穩定之耐久性。至於在現地工程中選材的取捨，藉由工廠製造膨潤土布的產品品質控制與管制以及針對工程設置的整體規劃與評估，才能達到膨潤土布產品的真正適用性。

關鍵字

膨潤土 ； 地工織物 ； 廢棄物掩埋場 ； 防滲阻水 ； 土工膨潤土布 ； 乾濕循環

並列摘要

Geosynthetic Clay liner (GCL) is the geosythetic developed in resent years. It is commonly used as the Hydraulic Barrier to decrease the liquid permeation. GCL is now broadly used in Europe and the US. It is applied to all kinds of constructions, such as water channel, pound, reservoir, and it is especially important in Landfill. The polluted and poisonous liquid due to the wastes would permeate the soil layer, and subsequently pollute the environment. In order to prevent the pollution, all Landfills have the Hydraulic Barrier. GCL has great performance as a material of liner.
To understand the effect of GCL applied as Hydraulic Barrier, many qualitative and property tests were done in this study. These tests were focused on Geotextile, Bentonite, and GCL itself, and three different types of betonites from various regions have been used. Moreover, the environment condition was added to simulation, so as to learn how the wet-dry cycling affect the Hydraulic Barrier property of GCL.
The testing result indicates that the Hydraulic Barrier effect of GCL decreased with wet-dry cycling. Due to the wet-dry cycling, the bentonite in GCL would be washed away by water flow, and furthermore formed cracks. Subsequently GCL would lose its Hydraulic Barrier efficiency.
During the wet-dry cycling of GCL, it’s found that the relativity between the permeation and stability of GCL is not obvious. GCL with great Hydraulic Barrier dose not necessarily has stable durability and engineering applicability. On the other hand, GCL with lower Hydraulic Barrier property might have more stable durability, when geotextile and manufacturing combined well. Hence, the GCL used in situ should be chosen according to the quality control of GCL manufacturing, the estimation and design of the whole construction. Thus the GCL product would fully reach its practicability.

並列關鍵字

Landfill ； Hydraulic Barrier ； Geosynthetic Clay liner ； Geotextile ； Bentonite ； Wet-dry cycling

參考文獻

【2】 王國海，「反向水流對地工織物抗阻塞潛能影響之研究」，私立中原大學土木工程學系碩士論文，民國九十年六月。

【3】 林上源，「應變率對地工加勁材基本性質影響之探討」，私立中原大學土木工程學系碩士論文，民國九十年六月。

【14】 謝啟萬，「地工合成材料常用檢測方法簡介」，地工技術雜誌第七十一期，pp. 13-28 (1999)。

【17】 Anthony W.Eith & John Boschuk & Robert M. Koerner.”Prefabricated Bentonite Clay Liners.”,Geotextile and Geomembranes 10,1991.pp.193~217.

【19】 ASTM D5993-99 ,”Standard Test Method for Measuring Mass Per Unit of Geosynthetic Clay Liners”, American Society for Testing and Materials, West Conshocken, Pennsylvania, USA.