Bearing Capacity of Strip Footings in various Locations with Respect to Sloping Ground

مهندسی عمران فردوسی

Article 1, Volume 29, Issue 2, October 2017, Pages 1-12   

Document Type: پژوهشی

DOI: 10.22067/civil.v29i2.45069

Author

maryam haghbin^*

azad university of Islamshahr

Abstract

The purpose of footing design is transferring structure load to soil without causing shear failure and extra settlement in soil. Therefore, footing bearing capacity should be considered in various projects. In special case, footings are placed in various positions with respect to slope ground and position of ground slope affects footing bearing capacity. In fact, slope affects failure surface of soil beneath the foundation remarkably and therefore, footing location with respect to slope must be cared to determine exact footing bearing capacity. In present paper, analytical method is presented based on soil stability beneath the footing. Virtual retaining wall method is used in present study and by applying equilibrium between active and passive forces on virtual wall, footing bearing capacity on reinforced and unreinforced soils is determined in various positions with respect to slope ground. Also, varied parameters include soil resistance, footing spacing with respect to slope ground, width and depth of foundation and seismic coefficient. Results indicate, in various depths and widths of foundation, bearing capacity of footing on flat ground is more than top of slope and bearing capacity of footing top of slope is more than down of slope. Also, bearing capacity of footing on slope is minimum. Based on proposed method, footing location with respect to slope affects passive and active force on virtual retaining wall and footing bearing capacity remarkably. Also, the proposed method can determine effect of slope angle and reinforcement on footing bearing capacity. Presented method indicates effective distance from slope crest is almost 4.5B. Finally, the predicted results are compared with those reported from analytical and experimental methods performed by others, indicating an acceptable agreement.

Keywords

Footing Bearing Capacity; Slope Ground, Seismic Coefficient; Footing Spacing, Depth and Width of Footing

Supplementary Files

1Edit.haghbin-1.pdf

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