Slopes are generally created because of the activities of nature and human. The movement of the surface of the earth and several human activities create uneven elevation of the earth and thus creating slope geometry. In reality, there are a lot of evidences of unsupported-stable slope, however in some other places, especially in the place with high rainfall intensity, slope failure is a common disaster. Hence it is necessary to establish a competent method for slope stabilization.
By looking at past studies conducted by Liang (2010) and Tsai (2011) as reference, using three-dimensional software FLAC 3D, this study intends to analyze the influence of drilled shafts, in terms of load transfer characteristic, in a slope stabilized using one-row drilled shafts. Comparisons are made between some analytical results obtained in this study and results reported by Liang (2010). Although there are some differences found, however, both studies show similar trend.
“Simplified 3D” study is also conducted to investigate the influence the effect of a simple three-dimensional modeling by applying offset distance to the one-row drilled shafts formation, making them into zig-zag drilled shafts formation. Some scenarios, in terms of various offset distances, are investigated to see their influence on the safety of the slope. Based on the conducted analysis, it is found that FS will be the highest when the offset distance is applied into one time the diameter of the drilled shafts.

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