Study on Dynamics of an Elastic Oscillator Coupled with a Rocking Wall

TL;DR

This study investigates the nonlinear dynamics of an elastic oscillator coupled with two types of rocking walls, analyzing their effectiveness in response suppression through computational modeling with OpenSees and MATLAB.

Contribution

It introduces a coupled oscillator-rocking-wall model with detailed nonlinear equations and compares the dynamic effects of stepping and pinned rocking walls.

Findings

Pinned rocking wall amplifies displacement across a broad spectrum.

Stepping rocking wall is more effective for flexible structures with heavier walls.

OpenSees simulations agree well with MATLAB solutions.

Abstract

This paper studies the dynamics of an elastic single degree of freedom oscillator (representing an elastic frame) coupled with a rocking wall. Two types of rocking walls namely stepping rocking wall and pinned rocking wall are presented and analyzed. For each case, full nonlinear equations of motions are calculated. The dynamic behavior of the systems shows mixed results in suppressing the dynamic response of the elastic oscillator. Through comprehensive analysis, pinned rocking wall amplifies the displacement along wide range of the spectrum, in the other hand, stepping rocking wall is the most effective especially in relatively flexible structures and with a heavier wall. This is mainly because of the pinned wall's mass works against its stability. In this study, a simple, oscillator-rocking-wall model is defined and analyzed using OpenSees and, the results from OpenSees shows a good agreement with equation of motion solution using MATLAB.