黄蒿纤维增强混凝土的受力性能试验研究

Experimental investigation on the mechanical properties of Artemisia annua fiber reinforced concrete

混凝土是一种典型的压强拉弱的建筑材料,利用抗拉能力突出的纤维补强混凝土的抗拉缺陷是一条常规思路,这其中韧性较强的植物纤维,如黄蒿纤维,是一种既经济又环保的材料。通过在混凝土中分层均匀地添加黄蒿纤维制得混凝土立方体试块,一方面通过对部分试块进行劈裂试验以探究黄蒿纤维对增强混凝土劈裂抗拉强度的效果;另一方面通过对部分试块进行标准立方体抗压试验以探讨黄蒿纤维对混凝土立方体抗压强度的影响。结果表明,黄蒿纤维的掺入可以有效地提高混凝土的立方体抗压强度,显著地提高混凝土的劈裂抗拉强度。此外,还基于复合材料力学理论对黄蒿纤维增强混凝土进行受力分析,推导出黄蒿纤维增强混凝土的抗拉强度与黄蒿纤维掺入率等参数之间的关系,并利用试验数据拟合了黄蒿纤维增强混凝土劈裂抗拉强度和立方体抗压强度关于纤维掺入率的经验公式,由此得出黄蒿纤维的最优掺入率,最后还讨论了黄蒿纤维的掺入对混凝土立方体抗压强度和劈裂抗拉强度产生影响的原因。

Concrete is a typical building material with good compression resistance and weak tensile properties. It is a common idea to use fiber with outstanding tensile strength to reinforce the tensile defect of concrete. Among them, plant fibers with strong toughness, such as Artemisia annua fiber, is a material that is both economical and environmentally friendly. In this paper, the concrete cube test block was made by layering the Artemisia annua fiber uniformly in the concrete. On the one hand, the split test of some test pieces was carried out to explore the effect of the Artemisia annua fiber on the splitting tensile strength of concrete. On the other hand, the effect of Artemisia annual fiber on the compressive strength of concrete cubes was investigated by performing a standard cubic compressive test on some test blocks. The results show that the incorporation of Artemisia annual fiber could effectively improve the cubic compressive strength of concrete and significantly increase the splitting tensile strength of concrete. In addition, according to the theory of composite mechanics, mechanical analysis for artemisia annua fiber reinforced concrete was completed to derive the relationship between the tensile strength of Artemisia annua fiber reinforced concrete and artemisia annua fiber incorporation rate. Meanwhile, based on the test data, the empirical formulas for the splitting tensile strength and cubic compressive strength of the Artemisia annua fiber reinforced concrete were fitted with artemisia annua fiber incorporation rate as independent variable, and therefrom the optimum incorporation rate of artemisia annua fiber was obtained. Finally, the reasons for the influence of the incorporation of Artemisia annua fiber on the cubic compressive strength and splitting tensile strength of concrete cubes were discussed as well.