Wave Motion Studies Originated in IEM Liao ZP (Institute of Engineering Mechanics, CSB) August 19 2004.

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