稻谷堆限侧膨胀体变模量与弹性模量的实验研究

Experimental Research on Bulk Strain Modulus and Elastic Modulus of Paddy Heap without Lateral Expansion

使用LHT-1型粮食回弹模量仪对稻谷堆(含水率为11.77%、12.95%、14.47%、15.75%、18.08%)的无侧向膨胀体变模量和弹性模量进行了实验测定。稻谷样品装入回弹模量仪中的圆柱形容器里,选定样品顶部的压应力分别为0、50、100、150、200、250、300 k Pa,对稻谷样品进行压缩与回弹实验。由实验数据计算得出样品所受的平均竖直压应力和平均围压,计算出体变模量与弹性模量。实验结果表明:在同一含水率下,随着平均围压的增大,稻谷堆的体变模量也增大;在同一围压下,随着含水率的增加,稻谷堆的体变模量减小。稻谷堆的体变模量与平均围压的关系可拟合为y=ax+b,其中系数a、b随含水率的不同而变化。随着加载、卸载次数的增加,粮堆的塑性形变增大,弹性形变略有减小。在同一含水率下,随着围压的增大,稻谷堆的弹性模量增大。

In this paper,by the LHT-1 rebound modulus tester （moisture content was 11.77%, 12.95%, 14.47%, 15.75% and 18.08%） no lateral expansion bulk modulus and elastic modulus of paddy heap were measured. The top compressive stress was selected as 0,50,100,150,200,250 and 300 kPa,respectively. Through theoretical derivation we can calculate the average vertical pressure and average confining pressure. The experimental results showed that in the same moisture content,with the increase of average confining pressure, the bulk modulus of paddy heap increased, under the same confining pressure, with the increase of the sample moisture content,the grain heap bulk modulus decreases .The he bulk modulus of paddy heap and the average confining pressure can be fitted out the two equation is y=ox＋b, the coefficient a, b with the water content varies. As the number of loading and unloading increases, the grain heap of plastic deformation increases, the elastic deformation of grain de-creases slightly,but no significant changes. In the same moisture content,with the increase of confining pressure,the elastic modulus of paddy heap increased.