Traction Boundary Conditions for Molecular Static Simulations

Xiantao Li; Jianfeng Lu

doi:10.1016/j.cma.2016.05.002

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arXiv · 1503.03555

Traction Boundary Conditions for Molecular Static Simulations

Xiantao Li·Jianfeng Lu

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Abstract

This paper presents a consistent approach to prescribe traction boundary conditions in atomistic models. Due to the typical multiple-neighbor interactions, finding an appropriate boundary condition that models a desired traction is a non-trivial task. We first present a one-dimensional example, which demonstrates how such boundary conditions can be formulated. We further analyze the stability, and derive its continuum limit. We also show how the boundary conditions can be extended to higher dimensions with an application to a dislocation dipole problem under shear stress.

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Xiantao Li, Jianfeng Lu. 2015-03-12. Traction Boundary Conditions for Molecular Static Simulations. https://doi.org/10.1016/j.cma.2016.05.002

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