Long in plan buried structures subjected to seismic wave propagation
Long in plan buried structures subjected to seismic wave propagation
ISBN: 978-88-98161-05-8
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Abstract:

The performance of long in plan buried structures being subjected to seismic waves is considered and studied in this section. The mechanism of structure loading is carried out through seismic wave propagation and wave passage, originating from the depth of the layered soil media. Important phenomena as reflection and refraction in non-homogeneous soil stratum are also considered. The model allows for analyzing the plane strain state in both frequency and time domain. Linear elastic behavior of the soil and the structure is assumed. Seismic input is considered to be elastic waves excited and propagating in the supporting half-space. Analysis methodology is based on the Fourier analysis of the soil-structure interacting system. Numerical 2D model of elastic layered half space is accomplished by direct boundary element method while the bearing structure skeleton is modeled by frame finite elements or boundary elements depending on the cross section of the structure. Connection between boundary and finite elements implies that both types of elements have common displacements and equal nodal forces. This approach is suitable to be applied for performance-based seismic design of culvert and tunnel systems as underground structures. Numerical model and methodology are verified by a number of numerical examples. The physical and numerical parameters of the model are discussed herein. Numerical verification of the results is carried out through ANSYS computer software. Comparable analyses show very good agreement between present method and results derived by the finite element model of ANSYS program.