Abstract：Relative merits and demerits of existing soil-structure interaction analysis models are discussed，and a new analytic model is presented based on practical engineering application. The three-dimensional elastoplastic bar model is used to simulate the upper-structure，and the contact between soil and base is simulated by using horizontal，vertical and rotary springs and dampers below the base，with different field categories being reproduced by changing the spring and damping parameters. Dynamic soil-structure interaction of a ten-story RC frame building is analyzed by utilizing the model established with the new method，through which effects of several factors，such as the foundation soil¢s shear wave speed，the rigidity of upper-structure，and the earthquake magnitude on seismic response of the interaction system are evaluated，and then the pattern of the energy dissipation under different situations is discussed. Analytical results show that roof displacement does not certainly increase when softer site or stronger rigidity of upper-structure with soil-structure interaction being taken into account，but softer site can decrease the seismic response，and augmenting the rigidity of upper-structure may increase the shear force and the bending moment. Although the change of upper-structure¢s rigidity affects little on energy¢s changing trend of interaction system，damping energy and strain energy of the upper-structure are the main dissipated energy of the soil-structure interaction system under different situations. When the earthquake magnitude changes，there are some different influences on the energy dissipation of the interaction system under different earthquake waves，and the function of damping energy and strain energy may be different.
