正向載重下針軋不織布的開孔徑分佈

Opening Size Distribution of Needle-Punched Nonwoven Geotextiles under Normal Loads

賴建斌(Jian-Bin Lai)

指導教授 ： 吳朝賢

淡江大學/工學院/土木工程學系碩士班/碩士(2015年)

https://doi.org/10.6846/TKU.2015.01024

摘要

本研究在五種不同的針軋不織布上下游處放置鋼珠，模擬在過濾系統中織布上游之土壤顆粒及下游之排水層，並在上方施加正向應力，探討正向應力與鋼珠粒徑對織布開孔徑之影響，後續再根據Giroud(1996)開孔徑經驗式與實驗結果做比較。
　　開孔徑量測結果顯示，針軋不織布在上下游鋼珠尺寸不變，僅改變正向力時，織布開孔徑會隨著正向力的增加，而變小。當下游鋼珠尺寸相同，施加的正向力也相同的情況下，織布開孔徑隨著上游鋼珠粒徑變小而變小。在上游鋼珠尺寸及施加之正向力不變的情況下，五種織布的開孔徑隨下游鋼珠尺寸的改變不明顯。
　　Giroud(1996)所提出預測開孔徑之經驗式與本研究試驗結果相互比較結果顯示出，當上游鋼珠尺寸越小時，試驗結果會越接近經驗式；上游鋼珠尺寸越大時，試驗結果會越遠離經驗式。

關鍵字

針軋不織布 ； 開孔徑 ； 正向應力 ； 鋼珠尺寸

並列摘要

The object of this study is to investigate the influence of field condition on pore size distribution of needle-punched nonwoven geotextiles. Experimental apparatus was designed and built to carry out a series of laboratory tests under pseudo-in-situ conditions. Steel beads with various sizes were placed upstream and downstream of a geotextile specimen to simulate soil particles and drainage layer in the field. The filtration system was subjected to normal pressure when the water flows through the system. Finally, test results were compared with those obtained from equations proposed by Giroud (1996).
　　Five types of needle-punched nonwoven geotextiles having different mass per area were employed to conduct the study. The test results indicate that (1) increase in normal pressure reduces pore size of all the tested geotextiles, (2) smaller diameter steel beads upstream the filtration system produces smaller pore size of a geotextile, (3) diameter of downstream steel beads has insignificant effect on the pore size of a geotextile, and (4) pore size of a geotextile obtained using smaller diameter steel beads upstream the filtration system is closer to the value obtained from equation proposed by Giroud (1996).

並列關鍵字

Needle-punched nonwoven geotextiles ； Pore size ； Normal pressure ； Steel bead ； Laboratory test

參考文獻

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