- 學位論文
靜態荷重對土壤 靜態荷重對土壤 -地工合成材過濾行為的影響
The Influence of Normal Stress on Filtration Behavior of Soil-Geotextile Systems
摘要
本研究主要探討不同的正向荷重對土壤-地工織物系統過濾行為之影響；試驗採用三款不同厚度之針軋不織布及四款扁絲織布進行一系列的試驗。在特別設計的艙室內，地工織物置入於5 cm厚的土層與排水鋼珠之間。於固定載重作用後，在不同的水力坡降下水流穿過土壤-織物複合層再流經排水層；並以Darcy定律求取滲透係數以描述整體土壤-織物複合層的過濾特性。試驗結果顯示土壤孔隙比隨載重增加而減少，且土壤-織物複合層的滲透係數也隨載重增加而反向遞減。因此可知，土壤-織物過濾系統加載後，造成土壤壓縮，同時織物也產生壓縮，可能引起織物孔隙變小，因而降低整體滲透性。但隨著載重越大，織物對整個複合體的影響逐漸縮小，滲透行為也就越接近純土壤行為。
並列摘要
The various normal stress on the filtration behavior of soil-geotextile composites has been studied through a series of tests using an experimental apparatus designed specifically for the laboratory tests. In these tests, the soil-geotextile composite was formed by inserting a piece of nonwoven geotextile between a 5-cm thick soil and a layer of steel beads. Normal stress was applied to the composite prior to the filtration test. Water was allowed to flow through the composite from the soil into a drainage layer at various hydraulic gradients. The permeability value was extracted by using Darcy’s law to characterize the filtration performance of the entire soil-geotextile composite. The test results revealed that the void ratio decreased with the increase of normal stress. The composite exhibited a reverse relationship between the permeability and the normal load applied; the permeability decreased with an increase in the normal load.