Résumé:
The main objective of this thesis is to investigate the impact of uncertainties on the bearing
capacity of shallow foundations under seismic loading by employing probabilistic approaches.
At the first stage, the Karhunen-Loève (KL) expansion method within the context of random
field theory was utilized to explore the influence of soil and earthquake parameter randomness
on the seismic bearing capacity. The seismic bearing capacity equations established by Conti
(2018) were applied in the analysis for two soil types supporting shallow strip footings: purely
cohesive soil and cohesive-frictional soil. The results indicated that, in the context of statistical
and probabilistic results, prioritizing the coefficient of variation is essential for accurately
capturing the variability and making reliable inferences. At the second stage, a formulation for
determining the seismic bearing capacity factor of a shallow strip footing influenced by
torsional surface wave propagation and resting on anisotropic non-homogeneous soil was
presented. The limit equilibrium method in conjunction with the pseudo-dynamic approach are
used. In addition to that, a reliability analysis based on Monte Carlo simulation was conducted
in order to incorporate the soil-earthquake uncertainties and investigating their effects. It was
found that the proposed seismic bearing capacity factor can be applicable in order to quantify
the torsional wave propagation, the anisotropy and the non-homogeneity of the soil properties.
