本研究採用長150 mm，直徑1.96 mm之鋼針模擬二向度 (Two-dimensional)均勻顆粒土壤，製作高500 mm之水平地盤與邊坡模型，探討水平地盤與邊坡之承載力，以兩種不同型式之基礎進行實驗，同時以5個自製雙向荷重計量測基礎下方正向力與剪力之分布，由偏心與傾斜載重情形，對承載力公式進行修正，並與各學者理論值比較。
本研究利用鋼針直剪試驗與鋼針模型承載力試驗，可知：
一、在鋼針雙曲線預測模型中，若代入鋼針直剪強度公式，並考慮摩擦角ϕ隨圍壓σn之增大而減小，其鋼針雙曲線預測模型可有較準確之結果。
二、基礎傾斜載重為承載力分析之重要因子，本研究發現不同坡度時的初始傾斜載重也有所不同，但不論在水平地盤還是邊坡，產生第一次尖峰強度時，傾斜載重角度皆落在正負1度間。
三、在探討邊坡承載力的偏心時，應考慮偏心的方向性，偏心靠近坡面時，承載力下降，偏心遠離坡面時，承載力上升，確認偏心方向性才能對基礎承載力做出正確的修正。
四、傳統承載力公式對於水平地盤的偏心修正是有效的，但不適用於邊坡的偏心修正，本研究提出一個解決上述問題的方法。

SUMMARY
In present study, bearing capacity of footings placed on level ground or slopes were investigated using reduce-scaled model tests. An idealized 2-D backfill consisting of uniform diameter steel rods was used as the test medium. The present study focuses on the effects of eccentricity and inclined load on the ultimate bearing capacity of footings. The following conclusions were obtained:

1.A hyperbolic model was established for simulating the nonlinear stress- displacement behavior of the steel rod backfill. The curved Mohr-Coulomb failure envelope was taken into account in the hyperbolic model.
2.The influence of load inclination on the ultimate bearing capacity is insignificant for the test conditions examined in the study because the load inclination angles observed at the peak footing load fell within ±1^°, regardless of the increase of the slope angles.
3.The load eccentricity on the footing had a dominant effect on the ultimate bearing capacity of footing, especially for the case of a footing situated on a slope.
4.Conventional bearing capacity equations for footings subjected to eccentric loads are applicable for the case of horizontal ground；they are not applicable for the case of slope. A new methodology alleviating the above-mentioned drawback is proposed.

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