Research On Dynamical Behavior Of Soil-Structure Nonlinear Interaction System Considering Spatial Effect

In this paper, the nonlinear dynamical theories are used to study the internalresonance of the elastic-plasticity foundation-multiple degree nonlinear structureinteraction system under the nonlinear coupling of horizontal oscillation and torsionoscillation. The works of this paper are as follows:1,The analysis method of nonlinear interaction of the soil-structure is advancedbased on the theory of nonlinear finite element. The elastic–plastic hardening modelis used to simulate soil body's nonlinear;the face-to-face contact element is used tosimulation soil and foundation. The program of the nonlinear relationships betweensoil and foundation is calculated. The relationship between horizontal force and slipdisplacement of foundation and the relationship between moment and rock angle offoundation is obtained, which is imitated as the stress-strain curve considering theslipping and wobbling of foundation.2, A bilinear stiffness model is taken as a restoring force of the unsymmetricalstructure, and the above nonlinear foundation model is used to simulate theelastic-plastic halfspace, then the massless foundation-soil-structure interactionmodel considering spatial effect is established. The Lagrange energy equation isused to build the nonlinear coupling equation of horizontal motion and torsionmotion.3,Perturbation analysis are used to analyze the above equation, the situations ofthe internal resonance are obtained. Through the analysis of numerical examples, thevibration characteristics and energy transfer behavior are discussed while somerelation lies in the horizontal stiffness and the torsion stiffness. And the numericalanalysis is carried out. The perturbation solutions and numerical solutions arecompared.4, Perturbation analysis are used to analyze situations of superharmonicresonance and subharmonic resonance under strong excitation. The nonlineardynamical behavior of superharmonic resonance and subharmonic resonance isstudied. The perturbation solutions and numerical solutions are compared.5, For multi-analysis the problem, the above research technique are used toanalyze the resonant reaction of soil-structure interaction system under differentparametric conditions, then some helpful conclusions are obtained. The nonlinear dynamical theories are used to study the nonlinear vibratesoil-structure interaction system, which are different from linear coupling system.And the resonant reactions under different parametric conditions are analyzedconsidering the nonlinear of structure and foundation. Then some helpfulconclusions are obtained. These make theoretical analysis be true of the practicalsituation, and these can provide more profound theoretic reference for theearthquake (vibration) resistant design and analysis.