振动摩擦机理及其非线性动力学特性

本文揭示了振动工况下散体物料的振动摩擦机理,给出了振动参数与土壤内摩擦力的关系曲线,并用数值试验方法模拟了复杂的振动摩擦压实过程,分别给出了振频和振幅对土壤孔隙比和轴向应力均值的关系曲线,验证了振动压实减摩机理的正确性.结果表明:松散物料在振动工况下,其颗粒间的摩擦力由静摩擦力转变为动摩擦力,随着振频和振幅的增加,摩擦阻力减小,从而土的内摩擦力减小,并且存在最优的振动强度使土壤在振动压实过程中的内摩擦力最小.建立了基于振动压路机的振动摩擦系统非线性动力学模型,利用渐进法得到了振动压实过程的共振响应和非共振响应.

Mechanism of Vibration Friction and Its Non-linear Dynamic Characteristics

The vibration friction mechanism of granular material in vibration case was revealed. A curve of vibration parameters to internal friction of soil was given. With numerical experiments, the complicated process of vibration friction compaction was simulated. Curves of frequency and amplitude to void ratio and mean stress were given, which verified the mechanism of vibration friction. The results indicated that static friction converted to dynamic friction in vibration case; both internal and external frictions decreased with increasing frequency and amplitude. An optimal vibration intensity can lead to the lowest internal friction. Finally, a nonlinear dynamic model of vibration friction system with compaction equipment was proposed. Its resonance and non-resonance responses were obtained.