地工合成材應用於提升淺基礎承載力之初步研究

Preliminary Study of Enhancing the Bearing Capacity of Shallow Foundation by Geotextile

鍾劭一(Shao Yi)

指導教授 ： 賴俊仁

朝陽科技大學/理工學院/營建工程系/碩士(2011年)

摘要

針對承載力較低之軟弱土層，工程上常於土壤中置入加勁材料組成一整體性複合材料，利用土壤與加勁材間的交互作用力，以提供抗張性進而改善工程品質。加勁土壤由於具有用地省、施工簡便等優點，已廣泛應用於大地工程中，目前國內有關加勁土壤的研究多著重於擋土結構或加勁邊坡，而關於加勁淺基礎方面之研究並不多見。
本研究利用二維有限差分軟體FLAC2D進行數值模擬與設計參數影響探討，先進行未埋入加勁材料之條形基礎承載力數值模擬，與傳統理論解比較以瞭解數值模擬之精準度；設計參數影響探討則是參照前人研究所使用之加勁材料性質，探討加勁條形基礎在不同加勁條件下，對其承載能力之影響；探討因素包括不同的埋置深度、延伸長度、埋置層數及層間距離等。
本研究得知於淺基礎下方置入加勁材，可使淺基礎承載力有明顯之提升；加勁於低強度之土壤時，所得到之加勁效益更加明顯，所以地工合成材料非常適合解決淺基礎於軟弱土壤承載力不足之問題。

關鍵字

有限差分法 ； 淺基礎 ； 加勁土壤 ； 地工合成材

並列摘要

For weak soils, geotextiles are often used to composed a compound material to improve the engineering properties of soils. The geotextiles provide tensile resistance by interaction with soils thus improve their engineering properties. The geotextiles have long been used in earth retaining structures, but relatively little study have been performed on their use in reinforced shallow foundation.
In this study we simulated the reinforced shallow foundation and study the effects of different parameters on its bearing capacity by FLAC2D Finite Difference program. First, the bearing capacity of a unreinforced strip foundation was simulated and compared with the theoretical solution to verify the numerical model. The effects of different parameters, such as the depth of the reinforcement, the length of the geotextile, the number of layers and the distance between layers were also studied.
This research verifies that the reinforced shallow foundation can provide higher bearing capacity, especially for weak soils. Thus, should be a good alternative for ground improvement.

並列關鍵字

Finite Difference Method ； Shallow foundation ； Reinforced soil ； Geotextiles

參考文獻

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