Journal of Structural and Construction Engineering

Journal of Structural and Construction Engineering

Estimation of the undrained bearing capacity of strip foundations on two-layer clay soils adjacent to the geogrid-stabilized slope under the effect of combined loading

Document Type : Original Article

Author
Ph.D Graduated, Department of Civil and Environmental Engineering, Shiraz University of technology, Shiraz, Iran
Abstract
The present paper aimed to determine the bearing capacity of strip footings on two-layered of clayey soil in the vicinity of geogrid-stabilized slope under the effect of combined loading by applying horizontal (H), vertical (V) and bending anchor (M) loads. To this aim, by modeling the finite elements of a strip foundation in ABAQUS software and analyzing the probe method based on the load-displacement controlled approach, the failure envelopes and the ultimate vertical (Vult/BCu1) and bending (Mult/B2Cu1) bearing capacities of strip footings under combined loadings in V-H and V-M spaces have been determined. The results obtained in two slope conditions, unreinforced and reinforced with geogrids, have been evaluated by performing parametric studies regarding the effect of changes in the distance of the footing from the edge of the slope, the number of geogrids, and the placement or angle of rotation of geogrids relative to the horizon (θ/β) on the bearing capacity of footings. The results showed that in both loading conditions, the reinforcement of the slope has a great effect on vertical (Vult/BCu1)- and bending (Mult/B2Cu1) bearing capacities. The optimal number of geogrids to achieve the maximum Vult/BCu1 and Mult/B2Cu1 were obtained as 3 and 4 geogrids, respectively. The optimal distance of the footing position relative to the crest of the slope to achieve the Vult/BCu1 and Mult/B2Cu1 were determined to be equal to 4 and 3 times the width of the footing, respectively. By increasing θ/β under both V-H and V-M modes, the failure envelopes and the changes in Vult/BCu1 and Mult/B2Cu1 decrease. The results of the present paper provide a clear understanding of the behavior mechanism of strip footings under the effect of a wide range of parametric changes for the development of new experimental equations and executive works.
Keywords

Subjects


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  • Receive Date 19 June 2023
  • Revise Date 29 August 2023
  • Accept Date 03 October 2023