路基压实状态固有频率特性与土体不同高度关系试验研究

该文通过试验研究,得到路基压实状态固有频率特性与土体不同高度关系。结果表明,不同高度各土样加速度时程曲线变化基本一致,不同高度土体各自的峰值加速度差异较大,呈非线性变化趋势。锤击力为235 N时,土样自振频率处于10~25 Hz宽频带之间。基于共振原理,当系统受到与本身固有频率相同的强迫振动时,系统振幅达到最大,从而产生“共鸣”,此时压实效果最好。因此在振动压实碾压作业时,选取合适的振动频率对于提高压实效率十分重要。

Through the experimental study,this paper obtains the relationship between the natural frequency characteristics of the compacted state of the roadbed and the different height of the soil.The results show that the time history curve of acceleration of soil samples at different heights is basically the same,and the peak acceleration of soil samples at different heights is significantly different,showing a nonlinear variation trend.When the hammer force is 235 N,the natural vibration frequency of the soil sample is in the wide band of 10~25 Hz.Based on the Resonance Principle,compaction is the best when the system is subjected to forced vibration of the same natural frequency as itself,and the system amplitude reaches its maximum,thus producing"resonance".Therefore,it is very important to select the appropriate vibration frequency to improve the compaction efficiency in the process of vibration compaction.