Probabilistic analysis of bearing capacity for sand overlying spatially random clay

The spatial variability of marine soils has received increasing attention from geotechnical engineers, particularly for quantifying the “probability” of specific performance outcomes. However, the bearing capacity of a typical marine stratum comprising a sand layer overlying spatially random clay remains underexplored in current literature. To address this gap, the present study employs Monte Carlo simulations (MCSs) in conjunction with advanced computational techniques to evaluate the bearing capacity of such layered soils. Utilizing upper-bound limit analysis and a range of practical statistical parameters, the study presents numerical results in the form of probabilistic design charts. These charts provide valuable tools for estimating the probability of failure ( PF ) associated with different safety factors. By enhancing the understanding of geotechnical reliability and safety, the proposed charts support more informed and rational design decisions. This approach not only bridges the gap between traditional deterministic methods and modern probabilistic assessments but also more accurately reflects actual marine soil conditions. • Investigated the bearing capacity of strip footings on sand underlain by spatially variable clay deposits. • Employed a probabilistic framework by using Monte Carlo simulations with Random Adaptive Finite Element Limit Analysis. • Developed probability-based design charts for designing sand-over-clay bearing capacity problems under spatial variability.