山坡地基地開挖擋土分析

Abstract

山坡地基地開挖擋土分析，本研究之重點為針對影響深開挖基礎穩定及變形的三個因素，擋土壁體側向變形、地表最大沉陷量δh,max 及支撐荷重，再配合工地現場監測資料與RIDO程式進行回饋分析。同時透過平地深開挖基礎之案例進行分析，比較其異同。期能找出山坡地基地開挖擋土分析時之土壤參數；或其他因子之修正方式。 本研究所得結果，就壁體變形型態而言；坡地開挖變形曲線趨向懸臂型。依RIDO程式回饋分析結果，影響程式計算之三項重要設計參數：擋土壁體勁度EI折減宜介於0.6~0.7、土壤與壁體間之摩擦角δ/φ介於1/3~1/2及地盤反力係數Kh介於100~175 N之間，反算結果與監測值較為接近。 關鍵字：深開挖、壁體變形、地表沉陷、支撐荷重、RIDO程式

For analysis of braced cuts on sloping ground, this research focus on three factors of stability and variable of deep excavation such as lateral retaining wall deformation, the maximum amount of ground settlement (δh,max ), and the strut load. To combine the monitoring data and RIDO formula produce the back analysis. Simultaneously, the differences between two factors derive from the analysis of the deep ground excavation. It looks forward to find out the soil parameter of braced cuts on sloping ground or other revisional methods. According to wall deformation from the result of this research, the deformation curve of braced cuts on sloping ground tends to cantilever style. Under the result from the back analysis of RIDO formula, three significant parameters are able to influence the result of formula calculation. They are the stiffness of retaining wall (EI:0.6~0.7); the angle of friction between soil and retaining wall (δ/φ:1/3~1/2); the coefficient of sub-grade reaction (Kh:100~175 N). The result of back analysis is closer to the value of monitoring. KEY WORDS：deep excavation, retaining wall deformation, ground settlement, strut load, RIDO program.