二自由度不对称迟滞振动压实系统的响应计算

分析了振动压实过程中被压实材料的不对称迟滞特性,建立了一种分段线性的不对称迟滞模型。在一次近似的前提下,利用谐波线性化方法,将迟滞非线性恢复力转化为等效刚度和等效阻尼表示,用优化算法求解频响方程,得到了二自由度迟滞振动压实系统的幅频响应。通过数值算例分析了模型参数对系统动态响应的影响,发现由于迟滞非线性的存在,随着激励幅度的增大系统会出现软化的趋势。

Response Calculation of Two Dof Asymmetrical Hysteretic Vibrating Compaction System

Based on analysis of the asymmetrical hysteretic nonlinearity of materials, a piecewise linear asymmetrical hysteretic model was built. By using harmonic linearization method, the nonlinear hysteretic restoring force was expressed as the combined force due to equivalent damping and equivalent stiffness. The response of two-DOF vibrating compaction system was derived by optimal approach. Numerical simulation result shows that the variation of parameters influences the dynamic response of system and the resonance frequency of system decreases along with the increase of excitation amplitude due to the hysteretic nonlinearity.