In this lecture, recent works of the author in non-local continuum models that account for material and/or structural length scales are discussed. In the context of certain observed phenomena that cannot be explained by classical continuum mechanics models, new continuum models are being postulated. An overview of two such non-local theories/models, in particular, Mindlin’s strain gradient or couple stress theories [1-4] and micropolar theories are presented in the context of reformulating the governing equations of beam and plate structures. The strain gradient (or modified couple stress) and micropolar theories will be discussed in the context of solving certain structural problems. Numerical examples involving the modified couple stress model for the bending of circular plates and a 2-D micropolar first-order shear deformation plate model for 3-D web-core sandwich panels are presented.
- A.R. Srinivasa and J.N. Reddy, J. Mech. Phys. Solids, 61(3), p. 873, 2013.
- Jani Romanoff and J.N. Reddy, Composite Structures, 111, 130-137, May 2014.
- Anssi Karttunen, J.N. Reddy, and J. Romanoff, Composite Structures, 185, 656-664, 2018.
- Praneeth Nampally, Anssi Karttunen, and J.N. Reddy, European Journal of Mechanics, A/Solids, 74, 431-439, 2019.
- Anssi T. Karttunen, J.N. Reddy, and Jani Romanoff, Int. J. Solids Struct., 170, 82-94, 2019.
Dr. Reddy is a Distinguished Professor, Regents’ Professor, and inaugural holder of the Oscar S. Wyatt Endowed Chair in Mechanical Engineering at Texas A&M University, College Station, Texas. Dr. Reddy, an ISI highly-cited researcher, is known for his significant contributions to the field of applied mechanics through the authorship of a large number of journal papers and 21 textbooks. His pioneering works on the development of shear deformation theories (that bear his name in the literature as the Reddy third-order plate theory and the Reddy layerwise theory) have had a major impact and have led to new research developments and applications. In recent years, Reddy's research has focused on the development of locking-free shell finite elements and nonlocal and non-classical continuum mechanics problems, involving couple stresses and surface stress effects.
Dr. Reddy has received numerous honors and awards. Most recent ones include: 2019 Timoshenko Medal from the American Society of Mechanical Engineers, 2018 Theodore von Karman Medal from the Engineering Mechanics Institute of the American Society of Civil Engineers, the 2017 John von Neumann Medal from the U.S. Association of Computational Mechanics, the 2016 Prager Medal, Society of Engineering Science, and 2016 ASME Medal from the American Society of Mechanical Engineers. He is a member US National Academy of Engineering and foreign fellow of Indian National Academy of Engineering, the Canadian Academy of Engineering, and the Brazilian National Academy of Engineering. In a recent world ranking of researchers in engineering by Stanford University, he is #13 in all fields of engineering and #5 in mechanical