Periodic Vibration and Bifurcation of Small Vibration Impact Pile Driver
Considering the plastic collision system of small vibration impact pile driver,the conditions of impact vibration and progressive motion of the system are analyzed.The possible different motion states of the system are discussed.The numerical simulation is used to identify the mode and parameter domain of the stable periodic at-tractor of the system in the two-parameter plane,and the bifurcation characteristics of the 1/n,1-/n,2/2n and 2-/2n(n≥1)attractor in the system are revealed by combining the single-parameter bifurcation diagram,phase diagram,time history diagram and attraction domain.The conditions for generating Sliding bifurcation,real-Graz-ing bifurcation and bare-Grazing bifurcation are obtained.The results show that the viscous characteristics and rubbing singularity between the vibrator and the pile frame are the important reasons for the unique dynamic char-acteristics of the plastic collision vibration system,and the system parameters for producing the best progressive effect are finally determined.