考虑打滑现象的振动压路机振动轮的滞回响应特性研究

摘要

The hysteretic recovering force of soil versus its displacement reveals a symmetrical hysteresis under a horizontal vibration's compacting.As the soil compactness is high enough,slipping appears between the vibration drum of a road roller and soil supface.Based on a bilinear symmetric hysteresis model,a piecewise 2-DOF dynamic model of the road roller was built according to soil property parameters.By means of numerical simulation,the influence of soil parameters and horizontal vibration excitation amplitude &frequency on the response of the vibratory drum were analyzed. Under the action of the symmetrical hysteretic force,the super-harmonic resonances of the drum occurred and their spectra revealed the fundamental wave plus higher odd harmonics.With increase in soil compactness,even and fraction harmonics appeared in the response spectra of the drum,it meaned the occurrence of slipping.Under a certain condition,the drum entered a complex quasi-periodic motion.Therefore,adjusting horizontal vibration excitation amplitude and frequency could suppress slipping,and make the drum have a stable double-periodic motion.%水平振动压实下土壤的滞回恢复力与位移呈现对称滞回特性，考虑土壤的密实度较高时振动轮在土壤面层发生脱耦打滑现象，采用双线性对称滞回模型建立分段的二自由度振动压路机动力学方程，在一次近似前提下，利用谐波线性法将非线性作用力线性化为等效刚度和等效阻尼。通过数值仿真研究振动轮在水平激振下非线性滞回响应特性。结果表明：在对称滞回力的作用下，振动轮发生超谐波共振，频谱呈现以基波为主，仅含明显的高奇次倍谐波特性。随土壤密实度的增大，振动轮频谱呈现明显的偶次倍和分数倍谐波成分，标志打滑的发生，一定条件下振动轮进入复杂的拟周期运动。合理调整激振参量，可在一定程度下抑制打滑，使得振动轮维持稳定的倍周期运动。