| 摘要: |
| 【目的】研究气干竹材的力学特性，为竹材的加工利用提供参考。【方法】使用配备高精度光学引伸计的Instron力学实验机，对毛竹从竹青到竹黄的纵向力学性质进行了精确测定。【结果】毛竹竹壁径向不同位置的力学性质差异很大，近竹青处的平均纵向弹性模量和抗拉强度分别达到25.41 GPa和297.21 MPa，远远高于近竹黄处的5.78 GPa和65.80 MPa，且从竹青到竹黄呈明显的梯度降低趋势。毛竹薄片的断裂为脆性断裂，近竹青处为顺纹理的纵向劈裂，竹中处呈现参差不齐的劈裂特征，近竹黄处为平整的横向断裂。【结论】竹材为天然高分子复合材料，其独特的力学特性源于自身组织含量的梯度性变化。 |
| 关键词: 毛竹 抗拉强度 弹性模量 力学性能 断口特性 |
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| 基金项目:国家自然科学基金重点项目（30730076） |
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| Gradient variation of longitudinal mechanical properties and fracture characteristic of Moso bamboo |
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| Abstract: |
| 【Objective】The research was done for better understanding of the mechanical properties of bamboo in air-dry condition.【Method】The longitudinal mechanical properties of Moso bamboo were investigated accurately by Instron tester equiped with advanced video extensometer.【Result】From outer to inner parts of bamboo culm,the values of average longitudinal elastic modulus and tensile strength reduced rapidly from 25.41 GPa and 297.21 MPa to 5.78 GPa and 65.80 MPa respectively,which presented a gradient-decreasing tendency.The fracture of Moso bamboo thin slice was brittle.However,the fracture apperance was disparate.In the outer part,it split along the longitudinal direction.In the middle part,it split and jagged.In the inner part,it presented very even transverse fracture.【Conclusion】Bamboo is natural polymer composites with distinct mechanical properties derived from its gradient design of content of different tissues. |
| Key words: Moso bamboo tensile strength elastic modulus mechanical properties fracture characteristic |
