AWARDEE OF MATHEMATICS AND MECHANICS PRIZE

WANG REN

Abstract

Wang Ren (A. J. Wang), born in Jan.1921 in Zhejiang, China, is an expert in mechanics of plasticity and geodynamics. He got his B. S. in Aero-engineering from Nat. S.W. Asso. Univ. Kunming, China in 1943. He went on to work as a design engineer in aircraft factories in Guiyang and Taizhong, China. In 1948, he became a research assistant at the University of Washington, Seattle, U. S. A. and studied for a M. S. degree in Aero-engineering. In 1950, he got a Rockefeller fellowship from Brown University, Providence and specialized on the theory of Plasticity. He got his Ph.D. degree in 1953. He took a job as an assistant professor in the Mechanics' department at Illinois Institute of Technology, Chicago. He was allowed to leave the country by the end of 1954. He arrived home in May, 1955, and soon joined the Department of Math. and Mech. at Peking University, Beijing.
His research in plasticity started from solving the continuous extension of notches in a plate subjected to tension by the theory of slip-line field.  The approach strictly follows the continuum mechanics scheme, which is different from the splitting approach of his advisor Prof. E. H. Lee. These are considered as initial investigations on fracture mechanics. He then work on the dynamic plastic response of a built-in circular plate subjected to an impulsive loading. It was regarded as a classical contribution and was followed by many experimental and theoretical works. In 1983, he and his student did some experimental work on the dynamic plastic stability of circular shell. They found that beside the usual threshold velocity used in the literature, there is a second critical velocity twice as high which changes the deformation shape from axi-symmetric to non-axi-symmetric with finite deformation.
In 1972, he was shifted from the Mechanics department to the Geology department. He started research in Geodynamics. He started from checking the driving mechanism of global tectonics proposed by S. G. Li to be the variation of rotation of the Earth. A multi-layered Earth model (up to 21 layers) was solved for the stress and deformation fields due to variation of rotation. The result can be used also to that due to Solar/Lunar attraction, it explains the relation between tidal stress and earthquake occurrence quite well. In 1976, after the great Tangshan Earthquake, he and his group started to solve for the stress field variations due to a series of great earthquakes in North China in the past 700 years, with the intention to predict the next great earthquake in this area. It is a space-temporal inversion scheme by using the results of past earthquakes to find the driving forces for the present tectonic movement. They also use the observed deformation data and stress measurements to constrain the driving forces on the tectonic plate movement in a similar inversion scheme.
Wang Ren has been the deputy director of National Natural Science Foundation of China (NNSFC), the president of Chinese Society of Theoretical and Applied Mechanics (CSTAM). He has chaired three IUTAM (International Union of Theoretical and Applied Mechanics) Symposia held in China on plasticity, rheology and geodynamics respectively and is editors to the proceedings. He has been editors to several International Journals on Mechanics and Earth Sciences and published over 170 papers both in Chinese and in English.