Kriging-Based Reliability Analysis of Strip Footings Resting on Spatially Varying Soils: Fid-Bau Portal

Kriging-Based Reliability Analysis of Strip Footings Resting on Spatially Varying Soils

Al-Bittar, Tamara / Soubra, Abdul-Hamid / Thajeel, Jawad

The probabilistic analysis of geotechnical structures presenting spatial variability in the soil properties is generally performed using Monte Carlo simulation (MCS) methodology. Despite being robust and accurate, MCS has low efficiency when considering the small failure probabilities encountered in practice. This is because it is very time-expensive in such cases due to the large number of simulations required to calculate a small failure probability with a small value of the coefficient of variation of this failure probability. In order to reduce the number of calls of the mechanical model when performing a probabilistic analysis, this paper uses the active learning reliability method combining kriging and Monte Carlo simulation (AK-MCS). This method is shown to be very efficient because the obtained probability of failure is very accurate, needing only a small number of calls to the computationally expensive mechanical model compared with MCS methodology. This study involves a probabilistic analysis at the ultimate limit state of a strip footing resting on a spatially varying soil using the AK-MCS approach. The soil cohesion and angle of internal friction are considered as random fields. The mechanical model is based on numerical simulations using the finite-difference code ${FLAC}^{3 D}$ . The obtained probabilistic numerical results are presented and discussed.