力学系与湍流国家重点实验室学术报告6.10 (报告人：Professor Stelios Kyriakides )
发布时间: 2010-06-07 03:29:00
SEMINAR SERIES
北京大学工学院 ![]()
力学与空天技术系
力学与空天技术系 湍流与复杂系统国家重点实验室
题目：ON THE CRUSHING AND ITS PROPAGATION IN CELLULAR MATERIALS
报告人：Professor Stelios Kyriakides
Research Center for Mechanics of Solids, Structures & Materials
The University of Texas at Austin，E-mail: skk（at）mail.utexas.edu
Abstract
Cellular materials both natural (e.g., wood, cork, trabecular bone) and synthetic (e.g., honeycombs, foams) have superior specific stiffness and strength as well as excellent energy absorption characteristics. When compressed, many of these materials exhibit first a nearly linear elastic regime that is terminated by an instability that leads to localization. Localized deformation is subsequently arrested, triggering its spreading to previously intact neighboring material. This propagation of localized deformation usually progresses with the load remaining nearly, and continues until the whole domain is crushed, in the process tracing an extended load plateau. The relatively low stress levels and extent of such plateaus are responsible for the excellent energy absorption characteristics of these materials. Experimental results from compression tests representative of several families of cellular materials will be used to illustrate this type of behavior, in each case highlighting the governing micromechanical mechanisms. The examples include honeycombs loaded in-plane (2-D crushing) as well as transversely (concertina folding), space-filling polymeric and metallic open cell foams, balsa wood and trabecular bone.
The onset of the first instability, its localization, the mechanism of arrest of local deformation and that of its spreading are unique to each cellular material. Indeed all of these mechanisms are dependent on the geometry of the cellular microstructure and on the mechanical properties of the base material (polymer, metal, bone, wood, carbon, etc.). Analytical and numerical results from 2-D honeycombs and 3-D foams will be used to illustrate the mechanics challenges involved in predicting these phenomena. The models are based on idealized periodic microstructures, as well as much larger domains with microstructurally accurate geometries and several base material systems.
About Speaker：
Stelios Kyriakides
Director, Center for Research in Mechanics of Solids, Structures and Materials, The University of Texas at Austin.
Professor, Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin.
EDUCATION
Ph.D. In Aeronautics (Solid Mechanics), April 1980, California Institute of Technology.
M.S. In Aeronautics, June 1976, California Institute of Technology.
B.Sc. First Class Honors, in Aeronautical Engineering, June 1975, University of Bristol, Bristol, U.K.
M.S. In Aeronautics, June 1976, California Institute of Technology.
B.Sc. First Class Honors, in Aeronautical Engineering, June 1975, University of Bristol, Bristol, U.K.
HONORS AND AWARDS
o Warner T. Koiter Medal, ASME, 2009
o Honorary Doctorate (Docteur Honoris Causa), INSA de Lyon (Institut National des Sciences Appliquées de Lyon), Villeurbanne Cedex, France, April 21, 2009. (For more see Ceremony).
o Mechanics Distinguished Lecturer of Spain, May 2007
o Cockrell Family Chair in Engineering No. 10, 2/2007-present
o Elected Member of the National Academy of Engineering, 2/2007.
o Midwest Mechanics Lecturer, 2002-2003.
o Elected Fellow of the American Academy of Mechanics, 1999.
o Elected Fellow of the American Society of Mechanical Engineers, 1997.
o Temple Foundation Endowed Professorship No. 1 UT-Austin, 8/1999-2007.
o Hayden Head Professorship in Engineering, UT-Austin, 8/1996-8/1999.
o ALCOA Foundation Unrestricted Grant, 1994.
o Walter L. Huber Civil Engineering Research Prize 1992.
o Engineering Foundation Faculty Excellence Award for 1984, 1992, UT-Austin.
o Outstanding Paper Award, ASME Division of Offshore Mechanics & Arctic Engineering, 1991.
o Honorary Doctorate (Docteur Honoris Causa), INSA de Lyon (Institut National des Sciences Appliquées de Lyon), Villeurbanne Cedex, France, April 21, 2009. (For more see Ceremony).
o Mechanics Distinguished Lecturer of Spain, May 2007
o Cockrell Family Chair in Engineering No. 10, 2/2007-present
o Elected Member of the National Academy of Engineering, 2/2007.
o Midwest Mechanics Lecturer, 2002-2003.
o Elected Fellow of the American Academy of Mechanics, 1999.
o Elected Fellow of the American Society of Mechanical Engineers, 1997.
o Temple Foundation Endowed Professorship No. 1 UT-Austin, 8/1999-2007.
o Hayden Head Professorship in Engineering, UT-Austin, 8/1996-8/1999.
o ALCOA Foundation Unrestricted Grant, 1994.
o Walter L. Huber Civil Engineering Research Prize 1992.
o Engineering Foundation Faculty Excellence Award for 1984, 1992, UT-Austin.
o Outstanding Paper Award, ASME Division of Offshore Mechanics & Arctic Engineering, 1991.
EDITORSHIPS AND EDITORIAL BOARDS
o Editor, International Journal of Solids and Structures, 10/05 - present
o Associate Editor, ASME Journal of Applied Mechanics, 6/94 - 6/2000
o Editorial Board, International Journal of Plasticity, 1/90 - present
o Editorial Board, International Journal of Non-linear Mechanics, 11/95 - 6/05
o Editorial Board, Journal of Composite Materials, 1/01 - present
o Associate Editor, ASME Journal of Applied Mechanics, 6/94 - 6/2000
o Editorial Board, International Journal of Plasticity, 1/90 - present
o Editorial Board, International Journal of Non-linear Mechanics, 11/95 - 6/05
o Editorial Board, Journal of Composite Materials, 1/01 - present
主持人：方岱宁 教授
时 间：6月10日（周四）下午3：00
地 点：力学楼434会议室
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