A 2D semi-analytical analysis of the time-dependent settlement of a shallow foundation placed near the soil slope

Document Type : Research Article

Authors

1 Department of Mining Engineering, Tehran University, Tehran, Iran

2 Rock Mechanics Specialist, Thurber Engineering Ltd., Vancouver, British Columbia, Canada

Abstract

To assess the safety of the foundation, the ultimate bearing capacity, as well as the settlement of the footing, should be studied. The bearing capacity of a footing built near the slope has been widely investigated. However, the published research work which focused on the settlement of the footing close to the slope is very limited. In many cases, the foundations should be built adjacent to a slope. Since geomaterial behavior is usually time-dependent, and due to the limited published research work on the time-dependent settlement of the foundation on a slope, in this study, a semi-analytical method has been used to obtain the elastic and viscoelastic settlement of a foundation rested on a slope. The proposed method has been developed based on the theory of elasticity by combining a transformed Airy stress function and finite difference method. To facilitate the use of the proposed solution, as well as investigating the effect of slope characteristics and footing geometry on the settlement, a set of elastic and time-dependent settlement charts have been proposed. The results indicate that the slope angle, the normalized footing distance from the crest, and the slope height play a prominent role in the settlement behavior of footing. By increasing the normalized footing distance or decreasing the slope angle, the settlement of the edges of the foundation tends to be equal and the behavior like a footing rested on a horizontal ground surface can be observed. Also, by decreasing the height of the slope, this behavior, i.e. behave like a footing on half-space, will happen in the smaller normalized footing distance.

Keywords


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