標題: Impedance matrices for circular foundation embedded in layered medium 作者: Liou, Gin-ShowChung, I. L.土木工程學系Department of Civil Engineering 關鍵字: Wave propagation;Impedance matrix;Dynamic stiffness;Soil-structure interaction 公開日期: 1-四月-2009 摘要: A numerical scheme is developed in the paper for Calculating torsional, vertical, horizontal, coupling and rocking impedances in frequency domain for axial-symmetric foundations embedded in layered media. In the scheme, the whole soil domain is divided into interior and exterior domains. For the exterior domain, the analytic solutions with unknown coefficients are obtained by solving three-dimensional (31)) wave equations in cylindrical coordinates satisfying homogeneous boundary conditions. For the interior domain, the analytical solutions are also obtained by solving the same 3D wave equations satisfying the homogeneous boundary conditions and the prescribed boundary conditions. The prescribed conditions are the interaction tractions at the interfaces between embedded foundation and surrounding soil. The interaction tractions are assumed to be piecewise linear. The piecewise linear tractions at the bottom surface of foundation will be decomposed into a series of Bessel functions which can be easily fitted into the general solutions of wave equations in cylindrical coordinates. After all the analytic solutions with unknown coefficients for both interior and exterior domains are found, the variational principle is employed using the continuity conditions (both displacements and stresses) at the interfaces between interior and exterior domains, interior domain and foundation, and exterior domain and foundation to find impedance functions. Some numerical results of torsional. vertical, horizontal, coupling and rocking impedances with different embedded depths will be presented and comments on the numerical scheme will be given. (c) 2008 Elsevier Ltd. All rights reserved. URI: http://dx.doi.org/10.1016/j.soildyn.2008.07.004http://hdl.handle.net/11536/7453 ISSN: 0267-7261 DOI: 10.1016/j.soildyn.2008.07.004 期刊: SOIL DYNAMICS AND EARTHQUAKE ENGINEERING Volume: 29 Issue: 4 起始頁: 677 結束頁: 692 顯示於類別： 期刊論文