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In the current paper, the consolidation settlement of a strip footing over a finite layer of saturated soil has been studied using the finite element method. In Biot’s coupled consolidation equations, the soil deformation and excess pore pressure are determined simultaneously in every time step which refers to the hydro-mechanical coupling. By considering a constant total stress throughout the time and by assuming that volume strain is a function of isotropic effective stress, uncoupled consolidation equations can be obtained using coupled consolidation equations. In these uncoupled equations, excess pore pressure and deformation are determined separately. In this approach, the excess pore pressure can be identified in the first stage. Using the calculated excess pore pressure, the soil deformation is determined through effective stress-strain analyses. A computer code was developed based on coupled and uncoupled equations that are capable of performing consolidation analyses. To verify the accuracy of these analyses, the obtained results have been compared with the precise solution of Terzaghi’s one-dimensional consolidation theory. The capability of these two approaches in estimation of pore water pressure and settlement and to show Mandel-Crayer’s effect in soil consolidation is discussed. Then, the necessity of utilizing coupled analyses for evaluating soil consolidation analysis was investigated by comparing the coupled and uncoupled analyses results.

One of the common features used for improving the bearing capacity of footings adjacent to a soil slope is reinforcement by geosynthetics. These elements may somehow isolate the soil inside of the geosynthetic and eliminate shear-stress mobilization. In this study, a new kind of three-dimensional geosynthetics called expandable braided sleeve (braid) and geogrid have used a laboratory modeling approach to investigate the effects of different variables on the bearing capacity of footings on soil slopes. Some parameters, including relative density and soil compaction, were assumed constant in all tests. In contrast, other variable parameters, including the vertical distance between the surface and the first layer of geosynthetics, the distance of a footing from the slope edge, and planar and tabular shapes of braid and geogrid were investigated. Results demonstrated that for the same conditions of some parameters, cylindrical reinforcement has a more significant effect than the planar form of the reinforcement concerning enhancing bearing capacity and settlement reduction. Inclusion of geosynthetic reinforcement can also reduce stress concentration and distribute the applied load, resulting in settlement reduction. Moreover, braid material was found to result in somehow better performance than geogrids in reducing settlement.

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