为了解决目前轻质混凝土力学性能不足的问题,开展了向轻质混凝土中掺入多种纤维以提高其力学性能的试验。采用正交试验方法分析了陶粒、玄武岩纤维和聚丙烯纤维这3种添加物对于混凝土抗压强度和最大抗剪荷载的影响。结果表明:陶粒替代部分粗骨料能够有效降低混凝土的自重并大幅度降低混凝土的抗压强度,但陶粒可以提升混凝土的最大抗剪荷载,最大提升幅度为13.7%;玄武岩纤维与聚丙烯纤维的掺入可以有效地提高混凝土的抗压强度和最大抗剪荷载,对混凝土抗压强度的最大提升幅度分别为9.7%和5.7%,对混凝土最大抗剪荷载的最大提升幅度分别为36.2%和13.1%。建立的混杂纤维混凝土抗压强度和最大抗剪荷载的预测模型能够精确地预测其抗压强度以及最大抗剪荷载。研究成果对混杂纤维混凝土的力学性能研究具有一定的参考价值。

In view of the insufficient mechanical properties of lightweight concrete, various fibers are added to lightweight concrete to improve its mechanical properties. The influences of adding ceramsite, basalt fiber, and polypropylene fiber on the compressive strength and maximum shear strength of concrete were investigated by using orthogonal test. Results reveal that replacing part of coarse aggregate with ceramsite could effectively reduce the dead weight of concrete, but also greatly reduce the compressive strength; ceramsite could improve the maximum shear strength of concrete, with a maximum rising rate of 13.7%. Both basalt fiber and polypropylene fiber could enhance the compressive strength and maximum shear strength of concrete, boosting the compressive strength by up to 9.7% and 5.7% respectively and maximum shear strength by 36.2% and 13.1% respectively. In addition, a prediction model for the compressive strength and maximum shear strength of hybrid fiber concrete is established.