Real-time dynamic hybrid testing for soil-structure-fluid interaction analysis

In traditional shaking table test semi-infinite foundation is difficult to consider; whereas in numerical simulation dynamic fluid-structure interaction is hard to calculate. To deal with the two difficulties,a newly developed real-time dynamic hybrid testing method is employed to solve the dynamic soil-structure-fluid interaction problems. Taking an aqueduct for example,the aqueduct-water system,called experimental substructure,is physically tested on a shaking table; while the semi-infinite foundation,called numerical substructure,is numerically modeled by a lumped-parameter model. The data exchange between the two substructures is performed in real-time; thus the dynamic response of the whole coupled system can be evaluated. Meanwhile,the finite element analysis is also implemented to simulate the test model. The comparison of the tested results with those obtained from the finite element analysis demonstrates that the real-time dynamic hybrid testing can achieve good test accuracy for this dynamic interaction problem. The tests of the soil-structure interaction (SSI) effects for different soils show that the soft soil reduces the structure response amplitude and extends the response period. With soil becoming hard,SSI effects decrease and the structure responses will ultimately converge to the solutions of rigid foundation.