Dr. Stewart Silling
Computational Multiscale Department
Sandia National Laboratories

Origins and Uses of Nonlocality in Continuum Mechanics

ABSTRACT: Nonlocal modeling has gained increased interest within the mechanics community in recent years. Advances in computer power have enabled the routine use of nonlocal modeling in applications. This talk will cover some of the motivations and useful features of nonlocality in mechanics. Among these is the regularization of singularities such as fracture and phase boundaries. In some cases, a nonlocal formulation with a suitable material model can reproduce phenomena, like self-induced curvature in a fiber, that would require an extensive modification of local theories. It will be demonstrated that nonlocality in a continuum description emerges from the coarse-graining of a smaller-scale system. Examples will be drawn from the mechanics of graphene sheets, microstructure evolution, and wave propagation. Some of the challenges and techniques in nonlocal computations will be discussed.

BIOGRAPHY: Stewart Silling received a Ph.D. in Applied Mechanics from the California Institute of Technology in 1986. He is currently a Distinguished Member of the Technical Staff at Sandia National Laboratories in Albuquerque, New Mexico, USA. He was an Assistant Professor of Engineering at Brown University prior to moving to Sandia. He has been a visiting faculty member at the California Institute of Technology and a Visiting Scholar at The Boeing Company. His research interests are mainly in theoretical and computational mechanics. He is known mainly as an originator of the peridynamic theory of mechanics. He received the Ted Belytschko Medal awarded by the U.S. Association for Computational Mechanics in 2015 in recognition of his contributions to the peridynamic method.