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Title: On Validation of a Two-Surface Plasticity Model for Soil Liquefaction Analysis
Constitutive modeling of granular materials such as sands, non-plastic silts, and gravels has been significantly advanced in the past three decades. Several new constitutive models have been proposed and calibrated to simulate the results of various laboratory element tests. Due to this progress and owing to the surge of interest in geotechnical engineering community to use well-documented constitutive models in major geotechnical projects, a more thorough evaluation of these models is necessary. Performance of the current models should be particularly evaluated in the simulation of boundary value problems where stress/strain paths are much more complex than the element tests performed in laboratory. Such validation efforts will be an important step towards the use of these models in practice. This paper presents the results of an extensive validation study aimed at assessing the capabilities and limitations of a two-surface plasticity model for sands in two selected boundary value problems, i.e. lateral spreading of mildly sloping liquefiable grounds. The results of a large number of centrifuge tests conducted during the course of four consecutive international projects known as Liquefaction Experiments and Analysis Project (LEAP) are used in this validation study. The capabilities and limitations of the two-surface plasticity model, initially calibrated against element tests, will be carefully assessed by comparing the numerical simulations with the results of the centrifuge tests from recent LEAP projects.  more » « less
Award ID(s):
1635524
PAR ID:
10282208
Author(s) / Creator(s):
;
Date Published:
Journal Name:
International Conference of the International Association for Computer Methods and Advances in Geomechanics IACMAG 2021: Challenges and Innovations in Geomechanics
Volume:
1
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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