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Title: Probabilistic Calibration and Prediction of Seismic Soil Liquefaction Using quoFEM
Liquefaction under cyclic loads can be predicted through advanced (liquefaction-capable) material constitutive models. However, such constitutive models have several input parameters whose values are often unknown or imprecisely known, requiring calibration via lab/in-situ test data. This study proposes a Bayesian updating framework that integrates probabilistic calibration of the soil model and probabilistic prediction of lateral spreading due to seismic liquefaction. In particular, the framework consists of three main parts: (1) Parametric study based on global sensitivity analysis, (2) Bayesian calibration of the primary input parameters of the constitutive model, and (3) Forward uncertainty propagation through a computational model simulating the response of a soil column under earthquake loading. For demonstration, the PM4Sand model is adopted, and cyclic strength data of Ottawa F-65 sand from cyclic direct simple shear tests are utilized to calibrate the model. The three main uncertainty analyses are performed using quoFEM, a SimCenter open-source software application for uncertainty quantification and optimization in the field of natural hazard engineering. The results demonstrate the potential of the framework linked with quoFEM to perform calibration and uncertainty propagation using sophisticated simulation models that can be part of a performance-based design workflow.  more » « less
Award ID(s):
2131111
PAR ID:
10501933
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Springer, Cham
Date Published:
Journal Name:
Proceedings of the 4th International Conference on Performance Based Design in Earthquake Geotechnical Engineering (Beijing 2022)
ISSN:
978-3-031-11898-2
ISBN:
978-3-031-11898-2
Format(s):
Medium: X
Location:
https://doi.org/10.1007/978-3-031-11898-2_152
Sponsoring Org:
National Science Foundation
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