• Proceedings of the Computational Structural Engineering Institute Conference
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• 1996.04a
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• pp.79-86
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• 1996

A boundary element method which utilizes the fundamental solution in the half plane is developed to analyze the multi-layered elastic media. The objective of this study is to derive numerically the fundamental solutions and to apply those to the exterior multi-layered domain problems. To obtain numerical fundamental solutions of multi-layered structural system, the same number of solutions as that of layers in Fourier transform domain are employed. The numerical integration technique is used in order to inverse the Fourier transform solution to real domain. To verify the proposed boundary element method, two examples are treated: (1) a circular hole near the surface of a half plane; and (2) a circular cavity within one layer of four layered half plane.

• Tunnel and Underground Space
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• v.12 no.3
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• pp.171-178
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• 2002

A dynamic analysis of a horseshoe_shaped tunnel near to cavity was performed to study the effect of the cavity on the dynamic behavior of the tunnel. In order to obtain the dynamic response of the tunnel embedded in a semi-infinite domain, a hybrid numerical technique was primarily developed. A dynamic fundamental solution in frequency domain for multi-layered half planes was derived and subsequently incorporated in the boundary element method. Coupling of the boundary element method for the far field with the finite element method for the near field is made by imposing compatibility condition of a displacement at the interface. The boundary element method is then coupled with the finite element method, which is utilized to model the near field including the tunnel and the cavity. In order to demonstrate the validity of the proposed technique, dynamic responses of single and multiply-layered semi-infinite structural systems are obtained by using the Kicker waveform and investigated in the limestone layer to find how the being and the location of the cavity affect the dynamic characteristics of the system.