About one way to integrate the equations of seismic vibrations of seismically isolated structures

Abstract

Objective. The purpose of the study is to develop a new method of analyzing seismic vibrations of seismically isolated structures.Method. The structure is modeled by a system with one degree of freedom with a nonlinear stiffness characteristic. In the absence of damping an analytical solution of oscillation equations on the phase plane is obtained. In this case the connection between speeds and displacements is accurate, and the law of uniformly variable motion is used to calculate displacements.Result. To take into account the attenuation, the law of change in mechanical energy at each integration interval is used.Conclusion. An example of calculating a seismically isolated system with a sliding belt and a spring with a linearly varying characteristic of stiffness is considered. The influence of dry friction and viscous damping on the displacement and acceleration of the system is analyzed.

Keywords

• seismically isolated structure
• oscillation equations
• phase plane
• nonlinear
• accurate solution
• take into account the attenuation in seismic insulation