The NHERI SimCenter is a nine-year research project that aims to advance the simulation of natural hazard impact on the built environment and communities. The SimCenter is developing several open-source workflow applications and an underlying scientific application framework. All applications built on this framework provide an OpenSees interface that enables users to use their existing models in advanced simulation studies, such as local and regional performance assessment, and uncertainty quantification (UQ). SimCenter applications provide researchers an opportunity to explore different extensions of their models by lowering the interdisciplinary barrier and encouraging collaboration. Among the applications, quoFEM provides access to UQ analyses with an easy-to-use, standardized interface. This work demonstrates the research enabled by quoFEM through the example of model calibration using PM4Sand, a soil constitutive model available in OpenSees. After an initial sensitivity analysis, the model is calibrated using Bayesian inference based on observations of hysteretic soil response from cyclic direct simple shear tests. The uncertainty in the model parameters is used in forward propagation to explore plausible lateral spreading scenarios due to seismic liquefaction. The results demonstrate the utility of quoFEM to the OpenSees community as a UQ-enabling tool.
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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.
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- Award ID(s):
- 2131111
- PAR ID:
- 10501933
- 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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Accepted Manuscript1.0
- Conference Paper:
- The DOI is not currently available.
