甘蔗茎秆在扭转、压缩、拉伸荷载下的破坏试验

甘蔗茎秆物理力学特性是建立甘蔗茎秆材料模型和茎秆在各种荷载下本构关系的基础。该文以“桂林—1号”甘蔗的茎秆为试验材料,采用自制的夹具,在扭转试验机上进行扭转试验,在材料力学万能试验机上进行拉伸、压缩试验。试验结果表明：在扭转荷载下,甘蔗茎秆的破坏形式为产生轴向裂纹;在压缩荷载下的破坏形式为屈曲,并产生轴向裂纹;在拉伸荷载作用下,蔗皮、蔗芯的破坏形式为断裂。对试验用 “桂林－1号”甘蔗茎秆的基部,切变模量的平均值为10.82 MPa,最大剪切应力的平均值为0.45 MPa;基部第一、二、三节的抗压强度平均值分别为14.47 MPa、9.93 MPa和8.24 MPa。基部蔗皮轴向、径向拉伸强度平均值分别为47.02 MPa和2.57 MPa,蔗芯轴向、径向拉伸强度平均值分别为6.71 MPa和1.34 MPa。

Failure tests of sugarcane stalks under torsion, compression and tension load

The mechanics of sugarcane stalks is the basis of developing its material model and constitutive equation under different loads. In the paper, torsion tests have been conducted for the variety "Gulin-1", using the torsion test equipment. Compression tests have also been conducted, for the same variety, using universal hydraulic test equipment. It is found that the sugarcane stalks have the failure form of axial direction crack under torsion load, and flections and axial direction crack under compressive load. For the variety "Guilin-1", the average of the shear modulus and shear strength are 10.82 MPa and 0.45 MPa, respectively. The average of compressive strength at the first, second, and third segment are 14.47 MPa, 9.93 MPa, and 8.24 MPa respectively. Tensile strength of the stalk barks in axial and radial direction are respectively 47.02 MPa and 2.57 MPa. After peeled, those are respectively 6.71 MPa and 1.34 MPa.