| The theory and test studies on dynamic soil-structure interaction (SSI) of some large-scaled projects including the building, earth-rock dam and bridge are carried out in the paper. Firstly, shaking table model tests are carried out to analyze the control performance of Tuned Mass Damper on building including soil-structure interaction (SSI). Secondly, A versatile, stochastic earthquake ground motion model accounting for the time variation of both intensity and frequency content is formulated and validated. Based on this model, an analytical method of fully nonstationary stochastic earthquake response is advanced. SSI effects of earth-rock dam and bridge structure are discussed through deterministic and stochastic seismic analysis, respectively. The main contents and conclusions of the study are described as follows:1. Large-scale shaking table model tests of dynamic soil-structure interaction are designed and carried out. The structure model is a complete 5-rooftruss, 2-span, 10-storied, frame structure. Through the contrast tests of the structure on rigid and soft soil, the effects of SSI on earthquake response of structure are discussed. By comparing the control performances of the tuned mass damper (TMD) located on the top of structure, the effects of SSI on the control performance of TMD are studied. Results dedicate the suppressing vibration control effects of TMD designed based on the condition of rigid base are not satisfied, even are negative when the structure is build on soft soil.2. SASSI2000 program for 3-D finite element analysis of soil-structure interaction are used to simulate the shaking table tests mentioned above. Comparisons between test results and calculated results dedicate the analysis model is good to simulate the performance of SSI system under seismic excitations. The test results and calculated results are coincident approximately. The rationality of numerical model and reliability of the test are verified simultaneously.3. A versatile, stochastic earthquake ground motion model named general stochastic seismic motion (GSSM) accounting for uncertainty and time variation of frequency content of real seismic excitations is formulated and validated. GSSM model is appropriate to simulate the stationary, intensity nonstationary and fully nonsationary process. Then, based on psedo-excitation principle, an analytical method of fully nonstationary stochastic earthquake response is advanced.4. Based on a high earth dam built on the deep overlying stratum, the time step-by-step integration method is used to analyze dynamic interaction between overlying stratum and dam. The results dedicate that SSI has some active effects on increasing the earthquake-resistance performance of the earth dam. The effects of frequency nonstaionarity on seismic response of earth dam are illuminated through interaction analysis under nonstationary stochastic excitations.5. 2-D integer finite element method and 3-D substructure finite element method are adopted respectively to analyze the earthquake response of group piles-soil -pier interaction system. Seismic response characteristic and dynamic interaction of group piles-soil -pier system are discussed. The fully nonstationary stochastic earthquake response method advanced in this paper is used to analyze SSI effects of group piles-soil -pier system for stationary and nonstationary excitation process. The dynamic reliability of interaction system is discussed preliminary. And, it is certified that frequency nonstationarity of seismic excitation should be considered.
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