Department of Mechanical Engineering, University of Alberta, Edmonton, Canada

Dr. Ru is currently a Professor in Department of Mechanical Engineering, University of Alberta, Canada. Dr. Ru received his doctorate in solid mechanics at Peking University, China, and then worked in the Institute of Mechanics, Chinese Academy of Science and held a number of visitor/research positions in several universities in Italy, USA and Canada. He joined the University of Alberta as a faculty member in 1997. Dr. Ru’s past research areas include plastic buckling of structures, mechanics of elastic inclusions, electroelastic mechanics, and some applied mathematics problems related to solid mechanics. His recent research interest focuses on solid mechanics at micro/nano scale, mechanics of carbon nanotubes, and cell biomechanics.

Speech Title: Some remarks on the Gurtin-Murdoch model of surface elasticity
Abstract: The (linearized) Gurtin-Murdoch model of surface elasticity has been widely used by numerous researchers and also caused some misinterpretation/confusion in the literature. The present work shows that the GM model can be derived, in a straightforward way, from a simple 2nd-order expression for the ratio of deformed surface area to initial surface area. This elementary derivation helps understand the essence of the GM model as compared to other existing surface elasticity models. It is also showed that the original GM model can lead to incorrect results when it is applied to thin-walled beams/plates. A modified GM model is requested to explain size-effects of micro/nano elastic beams/plates with different boundary conditions reported in the literature.