Study On Parameter Inversion Of Dynamic Soil-Box Foundation-Frame Structure Interaction System

The characteristics of dynamic soil-structure interaction systems under dynamic loads are very complicated. The analysis on such system still has a lot of undetermined factors up to now. One of the important factors is that the reasonable model parameters are difficult to be determined. To obtain the reasonable parameters for the analytical model by performing the parameter inversion based on limited experimental data would play a vital role in the prediction of the seismic response of structure and the study on decrease and isolation of vibration.First, based on a field large-scale dynamic soil-box foundation-frame structure interaction system in Hunan University, a 3-D finite element model and a 2-D lumped mass model are established in this paper. Second, through employing the 3-D finite element model and the dual objective function inversion method developed in this paper, and taking the measured fundamental frequency of system and the structure response to a harmonic excitation at the top of structure in field as the reversion objectives, the linear material parameter inversion is performed in ANSYS by using ANSYS Parameter Design Language (APDL). Third, through employing the 2-D lumped mass model and the single period objective function inversion method developed in this paper, and taking the measured structure response to a harmonic excitation at the top of structure in field as the reversion objectives, the linear physical and mechanical parameter inversion is performed in ANSYS by using APDL. The model and the single period objective function inversion method can be used for linear physical and mechanical parameters inversion of the other dynamic soil-box foundation-frame structure interaction systems under top harmonic excitation. Last, the 2-D lumped mass nonlinear model is established to simulate the dynamic soil-box foundation-frame structure interaction system, and the variables separated nonlinear parameters fitting method is proposed. The nonlinear parameters of the complicated dynamic soil-box foundation-frame structure interaction system are inversed according to this nonlinear calculating model and this inversion method.