摘要
建立了考虑渐进运动的小型振动冲击式打桩机的力学模型,研究了低碰撞恢复系数及塑性碰撞工况下碰撞振动的类型、分岔和系统参数对打桩机渐进率的影响,分析了系统存在的共存吸引子现象及其吸引域。弹性碰撞工况下,低激振频率区域的颤碰运动最终引起激振器和桩体同步渐进运动,桩体的渐进效果最好。塑性碰撞工况下,振动系统的部件在碰撞后呈现"同步"或"非同步"渐进运动,最大渐进量发生在1/1运动的参数域中;碰撞部件的擦碰接触产生Grazing分岔,导致p/n运动直接转迁为(p 1)/n运动或混沌运动。
A dynamic model of a small vibro-impact pile driver with progressive motions is established. Types of vibro-impact motions, bifurcations and the influence of system parameters on a progression rate are studied in the low coefficient of restitution and a plastic impact case. The coexistent attractors and their domains are analyzed. In an elastic impact case, the chattering impacts finally bring out the synchronous and progressive motion of a driver and a pile, and the best progression of a pile is achieved in the region of low forcing frequencies. In a plastic impact case, the synchronous or non-synchronous progressive motions of impact components occur immediately after the impact, and the best progression of the system occurs for T / 1 motion. Grazing bifurcation is generated via the grazing contact of two masses immediately before the impact, which leads the p / n motion to （p - 1） / n motion or chaotic motion immediately.
出处
《工程力学》
EI
CSCD
北大核心
2013年第11期227-232,共6页
Engineering Mechanics
基金
国家自然科学基金项目(10972095
11172119)
甘肃省自然科学基金重点项目(1107RJZA115)
兰州交通大学青年科学研究基金项目(2011014)
甘肃省高等学校基本科研业务项目(212093)
关键词
非光滑系统
振动
冲击
周期运动
分岔
non-smooth system
vibration
impact
periodic motion
bifurcation
