加勁材料之地工格網對土壤力學參數影響分析之研究

Effect of Reinforcing Materials on Mechanical Properties of Reinforced Earth

蕭哲翔(Jer-Shyang Shaw)

指導教授 ： 張子修

朝陽科技大學/理工學院/營建工程系/碩士(2009年)

摘要

本研究係由加勁地工材料對土壤力學行為之各項參數影響之研究，室內試驗時之材料參數為：(1)加勁材在不同土壤的含水量4%、7%和11%(平時、一般陣雨及暴雨)和瞬時降雨之抗阻能力(2)再舖設加勁地工格網之間距為15cm、其角度分別為30°、45°和60°。本研究並利用STABL邊坡穩定分析其安全係數，並比較有/無鋪設地工格網之安全係數增益比(%)。
分析結果發現長期降雨鋪設地工格網，對各種邊坡角度而言，鋪設地工格網較無鋪設地工格網之安全係數提高甚多。而在瞬時降雨之情形下，只有邊坡角度30°沒有明顯增加外，其他邊坡角度也同樣有明顯增加之趨勢。在有地表加速之情形下，鋪設地工格網較無加速度之情況，其安全係數增益效果較佳。研究數據顯示，在沒有地表加速度情況下，鋪設地工格網安全係數增加效益約14~73.7%，而有地表加速度其安全係數增加效益約21~115%。在長期降雨情形下，各邊坡角度有鋪設地工格網其安全係數增益比增加均安全係數較瞬時降雨狀況明顯。

關鍵字

加勁土壤 ； 邊坡穩定 ； 大型直接剪力試驗 ； 地工格網

並列摘要

The purpose of the proposed research is to investigate the influence of reinforcing materials on the mechanical properties of reinforced earth. The main parameters in this study include: (1)water content of the soils to be reinforced (4%, 7%, 11%) representing various in-situ conditions as normal, ordinary rain and storm condition respectively. (2)Spacing(15cm), angles between the fabric and slop(30%, 45%, 60%). The research decides on the percent of FS according to the FS obtained from Slope Stabilization Analysis.
The results of the study are as follows. In terms of angles, the use of reinforcing materials shows greater effect in Factor of Safety(FS) than the absence of reinforcing materials. In terms of ordinary rain, angles of 45% and 60% show the same effect except the angle of 30%. In terms of ground acceleration, when there is no ground acceleration, the FS presents loss improvement than that with ground accelerate. According to the results of analysis, when there is no ground acceleration, the FS rises with ratio to 14~73.7%; when there is intensity of ground acceleration, the FS rises up with a ratio of 21~115%. In terms of continuous rain, when there is reinforcing materials, with geogrid introduces more significant increase of FS than in storm conditions.

並列關鍵字

reinforced earth ； Slope Stabilization ； large scale direct shear test ； geotextile

參考文獻

中華地工材料協會，「地工合成材料加勁擋土結構設計與施工手冊」，台北，2001。

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