Dynamic Soil-Structure Interaction Analysis under Seismic Loads Using the Scaled Boundary Finite-Element Method

The novel scaled boundary finite-element method is a fundamental solution-less boundary-element method based on finite element technology, which combines the advantages of finite-element and boundary element methods. Only the boundary is discretized reducing the special discritization by one as in the boundary element method; no fundamental solution is required as in the finite-element method; and the radiation condition at the infinity is rigorously satisfied. Making use of a scaling center the geometry of the problems is transformed into the scaled boundary coordinates including radial and circumferential coordinates. The boundary of the problem represents the computational domain. The finite-element approximation on the circumferential coordinates leads to the analytical equation in the radial coordinate.It is the goal of this paper to employ the method for soil-structure interaction analysis under seismic loads. The formulation of the method for seismic loadings is detailed for both bounded and unbounded problems. The structure is coupled with the unbounded domain on soil-structure interface. To demonstrate the applicability, simplicity and accuracy of the method, numerical examples modelled with the scaled boundary finite-element method are addressed. The results are compared with the results obtained from the commercial finite-element software SAP. Good agreement is achieved.