小麦力学参数的三轴压缩试验研究

MECHANICAL PARAMETERS OF WHEAT IN TRIAXIAL COMPRESSION TESTS

小麦力学参数是仓储结构设计的基础数据,采用三轴仪对小麦进行了三轴压缩试验,获得了小麦试样的应力-应变关系曲线,利用莫尔-库伦准则确定了其强度参数,并计算得到其弹性模量.试验表明：小麦在固结不排水阶段的应力-应变曲线大致分为线弹性、应力强化、剪切面滑动和破坏等4个阶段;随着围压的增大,小麦试样弹性模量增大,在围压为50~200 k Pa时,弹性模量为0.715~2.422 MPa,并拟合出了小麦弹性模量和围压的关系曲线.试验结果可以为仓储结构设计中小麦力学参数的选取及小麦的颗粒流（PFC）数值分析提供依据.

The mechanical parameters of wheat is basic data for warehouse design. Triaxial compression test for wheat has been carried out using the automatic triaxial apparatus, and the stress-strain curves of wheat test samples is obtained. The strength parameters of wheat was determined by using Mohr-Coulomb criterion, and the elastic modulus of wheat bulk was calculated and analyzed. The test shows that, stress-strain curve of wheat under consolidated-undrained condition is mainly divided into four stages that are linear elasticity stage, stress hardening stage, shear plane sliding stage and failure stage, and the elastic modulus of wheat test sample increase with the increasing confining pressure, and the elastic modulus vary from 0.715 MPa to 2.422 MPa when the confining pressure is 50 kPa to 200 kPa. Then based on the experimental results, the curve was fitted for relationship between confining pressure and elastic modulus of wheat bulk. The test results provide the foundation for the selection of wheat mechanical parameters in designing warehouse and the granular flow （PFC） numerical analysis of wheat.