Safety Assessment of Pile-Founded T-Walls in the Face of Flooding Hazards: Fid-Bau Portal

Safety Assessment of Pile-Founded T-Walls in the Face of Flooding Hazards

Zhang, Liang / Wang, Lei / Turcios-Lovato, Kevin

Pile-founded T-walls are widely used for levees in New Orleans and other regions of the United States as a key infrastructure for flooding protection. Traditionally, the safety evaluation of pile-founded T-walls follows a simplified deterministic procedure. It is critical to evaluate the performance of the pile-founded T-wall in a probabilistic manner under the potential flooding hazards. This paper presents a study for the safety assessment of the pile-founded T-wall system in the face of flooding hazards using both deterministic and probabilistic procedures. First, the deterministic analysis for the performance assessment is performed using the three-dimensional finite-difference modeling. Then, uncertainties in geotechnical strength parameters are considered using Monte Carlo simulations and finite-difference modeling to evaluate the variability of the performance of the pile-founded T-wall under different flooding hazard levels in a probabilistic manner. The resulting factor of safety curves of pile-founded T-walls in both deterministic and probabilistic manners under various flooding hazard levels are analyzed. It is observed that the mean factors of safety obtained using Monte Carlo simulations are very consistent with the results from deterministic analyses. However, with the probabilistic analyses, the variability of the factor of safety due to input geotechnical uncertainties can be explicitly evaluated. The safety assessment framework is demonstrated through a case study of the pile-founded T-wall design.