Unretained excavations in clayey soils. Consolidation and overall stability by finite element method
DOI:
https://doi.org/10.14195/2184-8394_102_3Abstract
The behaviour of an unretained sloped excavation in an overconsolidated clay is analysed by a numerical model based on the finite element method. The model incorporates the Biot's consolidation theory (coupled formulation of the flow and equilibrium equations) and constitutive relations simulated by the p-q-θ critical state model. Special emphasis is given to the analysis in time, during and after the construction period, of the excess pore pressures, effective stresses, displacements and stress levels. On the other hand, taking into account the consolidation influence on the shear strength of soil, the variation in time of the safety is assessed using a computer program of overall stability analysis. The program, based on limit equilibrium formulations, uses the numerical results obtained from the finite element applications. Finally, comparisons of results are analysed by changing some parameters, namely the problem geometry and the over-consolidation ratio of soil.
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References
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