1963年法國工程師Henri Vidal由觀察鳥類利用草和泥結巢的過程，啟發了加勁土壤的觀念，經過不斷的研究，提出鋼片結合混凝土面板，用以構築加勁擋土牆，從此，加勁土壤系統才逐漸受大地工程界重視。加勁土壤的主要觀念是在土壤中加入可提供束致力之加勁材料，藉土壤與加勁材之互制作用，將土壤所承受之應力傳遞至加勁材，以束制土體之變形，進而達到加勁及整體穩定效果。
台灣部分地區地質為含有高比例細粒料的軟弱土壤，加上台灣降雨豐沛，因此，在淺基礎結構物興建時必然會遭遇到，例如承載力不足或是沉陷量過大以及內部孔隙水壓影響等問題，所以有了運用加勁材料來解決承載力不足的想法，在選定所用的加勁材料後，如何埋設便成為了一項重要的課題，如何以最有效的方式鋪設加勁材，同時兼顧地盤之承載力，藉由不同的加勁材擺設，研究其對承載力之影響與貢獻。此為本研究欲探討的主題之一。
本研究以南投眉溪砂作為試驗土體，在不同的加勁條件下，來探討承載力之變化趨勢、孔隙水壓對承載力之影響以及加勁材的受力情況。試驗結果發現，加勁材的覆蓋率與埋置層數對承載力之影響較加勁材長度來的大，此外，這兩項因素也會影響到承載力之初期勁度，使得土壤在微小沉陷量時，承載力能夠獲得提升，這點於實務上是非常重要的，另外，加勁材在軟弱地盤中加勁效果會較堅硬地盤來得好，所以地工加勁材非常適合解決軟弱土壤承載力之問題，而研究中所埋設之地工不織布亦能有效的幫助超額孔隙水壓的消散，對於基礎穩定性有很大的幫助。

In 1960’s, French engineer Henri Vidal introduced the idea of reinforced earth. After decades of studies and implementation the concept of reinforced earth is now successfully applied in wide variety of soil structures, including foundations and soil retaining walls. The principle of reinforced earth is to introduce reinforcing material to provide additional constraining forces in soils. Using the interaction between soil and reinforced material, the stress bear by soil is transferred to the reinforcing material to prevent the soil body from deforming, thus increase the strength and ductility of the reinforced soil.
The test medium used in this study is a river sand from Mei-Shi Nantou. A dry density γd of 15kN/m3 was used for all test of grounds. De-aired water was supplied from the base of the sand box to saturate the horizontal test grounds. In addition to the footing loads and settlements, pore water pressure and strains of reinforcement were measured at a frequency of 2 Hz in the loading tests on reinforced and unreinforced horizontal sandy grounds using a 100 mm-wide rigid strip footing. A major finding from this study is the significant influence of ground saturation to the behavior of bearing capacity. In particular, the influence of excess pore water on the delayed mobilization of reinforcement forced and ultimate footing pressures. A generic model for describing the mobilization of excess pore water pressure in reinforced horizontal ground is necessary for an accurate prediction of ultimate bearing capacity of saturated reinforced grounds.

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