Wave Motion Studies Originated in IEM

Liao ZP(Institute of Engineering Mechanics, CSB)

August 19 2004

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Professor Liu Hui Xian

Initiating the studies in IEMGreat support to the studies

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Problem Statement

• Near-field wave motion

• Numerical Simulation

• Open, Complicated System of large scale

Remark: Common Problem

Fields in Electromagnetics

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Goal: High Efficiency Accuracy and Stability

Results:Finite Element Decoupling Technique

for Simulation of the Near-Field Wave Motion

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Framework of Decoupling Technique(1970s, 1980s)

Decoupling

• Waves passing through the boundary

• Wave Motion in the interior

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• Transmitting Boundary conditions Liao ZP, etc., Siencia Sinica, 27(10), 1063-1076, 1984;

Liao ZP, etc., Soil Dyn. Earthq. Eng., 3(1), 174-183,1984

• Decoupling Simulation of Waves

in the Interior of the SystemLumped Mass and Consistent MassLiao ZP ， Earthq. Eng. Eng. Vib.， 4(2)， 1-14， 1984 (in Chinese)

• Framework of the decoupling technique

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Recent Studies (1990s - now)

Theoretical basis of the boundaryPlane wave assumption and Radiation conditions at infinity

Liao ZP, Sciences in China, 42(2), 177-186, 2001

Stable ImplementationSemi-empirical technique to enhance the stability

Classification of instabilities Causes Measures

Liao ZP, etc., Acta Geophysica sinica, 45(4), 554-568, 2002

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Complicated Waves in the Interior The technique is generalized to include:

Contactable Cracks

Plasticity, Viscosity and Elasticity

Constant Hysteretic Damping

Liu JB, etc., Acta Mechanica Sinica, 15(1), 63-72, 1999

Liu JB, etc, Comp. Meth. Appl. Mech. Eng., 121, 187-200, 1995

123, 287-298, 1995

Li XJ, etc., Acta Seismologica Sinica, 8(3), 447-456, 1995

Liao ZP, An Introduction to Wave Motion Theories for Engineering

Academic Press, Beijing ,2002 (in Chinese)

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Applications

Professor Chen HQ

Earthquake Resistance Design

Of Xiao-wan arch dam(192m)

I = Ⅷ,Ⅸ

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11A sketch of F.E. modeling of Xiaowan arch dam

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Concluding Remarks

Forward and Inverse Problems

Cooperation of Different Disciplines