本研究運用元素釋放法（Element Free Method, EFM）來處理單向度壓密的問題，結合元素釋放法及有限差分法的使用，探求土層在一廣大平面的加載下，受壓土層之水壓消散情形。 有限元素法處理壓密的沉陷問題，需重組元素與節點的資料，才能繼續求解。而元素釋放法是以「移動式最小平方法」（moving least-square, MLS）近似內插的觀念，以建立形狀函數，而後組構勁度矩陣，處理定義域內節點之資料，為無網格法的一種，只需考慮各離散節點的資料，積分網格無須重新組立。引用高斯積分權值調整法，各積分點依權值大小，對應劃分各自的分配區域；當定義域穿越某個高斯點所分配的區域時，在定義域內的分配區域，則為剩餘的權值大小。 本文是以德在基的單向度壓密理論為發展，數值驗證與德在基理論解相當接近。而德在基對於定義域的假設，並沒有隨著時間而改變。本文加入積分權值調整法後，土層厚度隨著時間增加，可看出壓縮趨勢，較符合真實現象的發生；由於排水路徑的壓縮變短，壓密速率比德在基理論來得快一些。 In this paper, Terzaghi’s one-dimensional consolidation equation is solved numerically by using the Element Free Method in which the moving-least-square method is employed along with a modified Gauss integration scheme operating on a group of fixed integration cells. A backward finite difference method is used for analyzing the time domain. Examples of various initial and boundary conditions as well as loading conditions are analyzed to show the capabilities of the EFM. Results from the EFM simulation have been shown a complete success when they are compared with analytical solutions whenever available. It is worth to note that the consolidation settlement calculated in each numerical time steps can easily be taken into consideration for the calculation of a next time step without changing the integration cells when the modified Gauss integration scheme is used.
