甘蔗根部蔗芯工程弹性常数的试验研究

Experimental study on engineering elasticity constants for the sugarcane core of sugarcane root

为测试甘蔗根部蔗芯弹性工程常数,采用多功能组合试验机、静态电阻应变测试仪和扭转试验机,对甘蔗根部蔗芯进行单轴压缩和扭转试验,用电测法和扭转法测试出蔗芯12个弹性工程常数,并对数据进行了独立样本t检验。结果表明:蔗芯X方向(纤维方向)与Y、Z方向(垂直纤维方向)力学性能存在显著差异,Y、Z方向间无显著差异。由此认为甘蔗蔗芯单向复合材料模型合理,并据此对12个常数进行修订,最终得到7个独立弹性工程常数,即:E_x=813MPa;E_y=152.5MPa;μ_(xy)=0.53,μ_(yx)=0.105,μ_(yz)=0.265;G_(yz)=17.75MPa,G_(zx)=1.14MPa。试验结果为建立甘蔗材料有限元模型,对复杂工况下切割器与甘蔗相互作用的动力学过程进行计算机仿真分析,揭示刀盘切割甘蔗时各种因素对甘蔗宿根破头影响机理提供了初步理论依据。

In order to measure the engineering elasticity constants of sugarcane core of root,a series uniaxial compression and torsion experiments were carried out with sugarcane core up root by the multifunctional combined testing machine,static resistance strain indicator and torsion testing machine.12 engineering elasticity constants of sugarcane-core were analyzed and calculated with electrometric method and torsion method,and then,experimental data was analyzed with independent sample t-test.The analysis results show that mechanical property of sugarcane-root core has significant difference at Xdirection（direction along fiber）and Y,Zdirection（direction of vertical fiber）,but indifference at Yand Zdirection.Thus,the unidirectional composite material model is considered to be reasonable.According to this conclusion,12 constants were revised,7constants were finally get,which are Ex =813MPa;Ey=152.5MPa;μxy=0.53,μyx=0.105,μyz=0.265;Gyz=17.75 MPa,Gzx=1.14 MPa.The experimental results can provide the primary theoretical basis for establishing FE model of sugarcane,doing simulation analysis on interactions between sugarcane and cutter,and revealing how the various factors affect the sugarcane ratoon damage rate in cutting process.