Virtual element method for the numerical simulation
of long-term dynamics of transitional environments
A. Mazzia, M. Ferronato, P. Teatini, C. Zoccarato
Dept. of Civil, Environmental and Architectural Engineering,
University of Padova, Padova, Italy
ABSTRACT
The prediction of long-term dynamics of transitional environments, e.g., lagoon evolution,
salt-marsh growth or river delta progradation, is an important issue to estimate the
potential impacts of different scenarios on such vulnerable intertidal morphologies. The
numerical simulation of the combined accretion and consolidation, i.e., the two main
processes driving the dynamics of these environments, however, suffers from a significant
geometric non-linearity, which may result in a pronounced grid distortion using standard
grid-based discretization methods. The present work describes a novel numerical approach,
based on the Virtual Element Method (VEM), for the long-term simulation of the vertical
dynamics of transitional landforms. The VEM is a grid-based variational technique for the
numerical discretization of Partial Differential Equations (PDEs) allowing for the use of very
irregular meshes consisting of a free combination of different polyhedral elements. The
model solves the groundwater flow equation, coupled to a geomechanical module based on
Terzaghi’s principle, in a large-deformation setting, taking into account both the geometric
and the material non-linearity. The use of the VEM allows for a great flexibility in the
element generation and management, avoiding the numerical issues connected with the
adoption of strongly distorted meshes. The numerical model is developed, implemented
and tested in real-world examples, showing an interesting potential for addressing complex
environmental situations.
