土壤固有频率与孔隙度、含水率的关系研究

为确定土壤含水率、土壤孔隙度与土壤固有频率的关系,采用自制的土壤压实机械进行土壤试样制作,运用试验模态分析法,进行不同含水率和孔隙度下土壤固有频率的测定。获得了不同孔隙度下土壤固有频率和土壤含水率的关系曲线以及不同含水率下土壤固有频率和土壤孔隙度的关系曲线。分析结果表明:土壤试样含水率为3%~15%时,当土壤孔隙度一定,土壤试样固有频率除含水率为3%时呈线性增长,其余含水率均为先增大至含水率为9%左右后开始降低;土壤试样孔隙度为40%~48%时,当土壤含水率一定,土壤的固有频率随着土壤孔隙度的升高而增大。试验结果可为研究不同农机具作业后土壤—车辆振动系统的传递提供依据。

Effects of Soil Porosity and Water Content on Natural Frequency of Cultivated Soil

The relationship between soil moisture content,soil porosity and soil natural frequency was determined.The soil samples were made by self-made soil compaction machine,and the natural frequency of soil was measured under different moisture content and porosity by experimental modal analysis.The relation curves between natural frequency and soil moisture content under different porosity and the relation curves between natural frequency and soil moisture content under different porosity were obtained.According to the analysis results,when the moisture content of the soil sample is 3%-15%,when the soil porosity is certain,the natural frequency of the soil sample increases linearly except when the moisture content is 3%,and all the other moisture content first increases to about 9%and then starts to decrease.When the porosity of soil sample is 40%-48%,when the soil moisture content is constant,the natural frequency of soil will increase with the increase of soil porosity.The results of this experiment can provide a basis for studying the transmission of soil-vehicle vibration system after different agricultural machinery operation.