本文之目的在於使用FLAC二維數值分析工具及用RIDO一維數值分析工 具,建立U型擋土牆模型,討論採用如何在RIDO中以彈簧模擬結構側牆效應 之行為,建立RIDO近似之分析模型,以提供初步設計之參考。如果在近似 分析中發現有縮減回撐之可能性,則在簡易小型的工程中,可以直接縮減 回撐,複雜的案例中輔以FLAC二維數值分析進行最後細部設計定案,以降 低施工成本。 研究結果顯示在(1) 永久側壁彎曲勁度遠大於臨時擋土壁勁度(2) 永 久結構底版未設置抗浮榫接剛棒,或抗浮榫設計不得提供水平連接之設計 (3) 永久側壁設置時,最多僅於1 層支撐未拆除之條件限制下,U 型擋土牆 結構之支撐拆除過程,RIDO 可以採用單一彈簧合理模擬永久側壁之貢獻及 拆撐行為。
In this research, a U-shape retaining wall model is constructed using both FLAC, a two dimensional numerical analysis software, and RIDO, a one dimensional numerical analysis software. In the first stage of analysis, RIDO model is used with a spring to simulate the behavior of a structural side wall. In simple and small projects, if reduction of backward bracing is found in the analysis, we can reduce the bracing as suggested by the analysis. In complicated projects, FLAC model is used for the final design in order to reduce the construction costs. It is found in this research that: (1) Stiffness of permanent side wall is always larger than that of temporally bracing.; (2) When the permanent structural base slab has no anti-floating steel key, or the anti-floating steel key is not allow to provide horizontal connection design; (3) With permanent side wall, and limited to only one layer of bracing, using a single spring to simulate the permanent side wall in RIDO analysis provided a reliable result.