Zdenek P. Bazant to Receive the ASME Nadai Medal

NEW YORK, Sept. 25, 2008 -- Zdenÿk P. Baÿant, Ph.D., a resident of Evanston, Ill., and McCormick Institute professor and W. P. Murphy professor of civil engineering at Northwestern University, will be honored by ASME. He is being recognized for demonstrating spurious localization instability in strain-softening models of quasibrittle materials, devising a remedy by crack-band and nonlocal damage formulations, discovering and experimentally validating the energetic size effect law for such materials, and showing applications to particulate and fiber composites. He will receive the Society’s Nadai Medal.

The medal, established in 1975, recognizes significant contributions and outstanding achievements which broaden the field of materials engineering. The award will be presented to Dr. Baÿant during the 2008 International Mechanical Engineering Congress and Exposition, which is being held in Boston, Oct. 31 through Nov. 6.

Baÿant joined the faculty of Northwestern University in 1969 as associate professor of civil engineering. He was promoted to full professor in 1973 and has been W.P. Murphy professor since 1990 and, simultaneously, McCormick Institute professor since 2002.

Although Baÿant has made major contributions to fracture mechanics, structural stability, plasticity, creep, constitutive modeling and probabilistic mechanics, he is best known for his size effect law. His impressive publication record includes almost 500 refereed journal articles and six books. With ca. 8,700 citations and the H-index of 43, he has been among the original top 100 ISI Highly Cited Scientists in Engineering since 1991.

Prior to 1984, all the experimentally observed size effects on structural strength were attributed to material strength randomness and described by Weibull statistics. Baÿant is known worldwide for showing, beginning with his two landmark papers in 1976 and 1984, that this was not true for brittle heterogeneous materials. He introduced the novel concept of size effect caused by stress redistribution with a release of stored energy due to stable growth of large fractures or large damage zones prior to failure. Using asymptotic matching techniques, he derived a simple size effect law bridging the power-law scalings of classical fracture mechanics and plasticity. With his assistants, he verified his law experimentally for fiber composites, concrete, rocks, sea ice, toughened ceramics, rigid foams, etc.; demonstrated its use for experimental identification of cohesive fracture characteristics; and generalized it (1991, 2004) for combined energetic-statistical size effect. His crack-band model (1976, 1983) is now widely used to simulate the size effect computationally. He initiated (in 1984) the nonlocal and second-gradient models with material characteristic length, overcoming spurious mesh-size sensitivity and capturing the localization of distributed softening damage.

An ASME member, he served on various technical committees. In 1997 he received the ASME Worcester Reed Warner Medal.

Baÿant is a member of the National Academy of Sciences, National Academy of Engineering and American Academy of Arts and Sciences, and an honorary member of the American Society of Civil Engineers. He is also a Fellow and past president of the Society of Engineering Science; a Fellow of the American Concrete Institute; past president of the International Association of Fracture Mechanics for Concrete and Concrete Structures; and a member of the American Chemical Society, the American Institute of Aeronautics and Astronautics, and other associations.

Baÿant received his Ing. degree in civil engineering from Czech Technical University (CTU) in Prague in 1960. He earned his Ph.D. at the Czech Academy of Sciences, Prague, in 1963; and in 1967 he earned his Docent Habil. at CTU. He holds six honorary doctorates. Baÿant is a registered structural engineer in Illinois.

Founded in 1880 as the American Society of Mechanical Engineers, ASME is a not-for-profit professional organization promoting the art, science and practice of mechanical and multidisciplinary engineering and allied sciences. ASME develops codes and standards that enhance public safety, and provides lifelong learning and technical exchange opportunities benefiting the global engineering and technology community.