聚丙烯纤维增强混凝土拉压比试验

针对聚丙烯纤维对混凝土强度和拉压比影响的问题,采用标准试验方法,对不同纤维掺量和不同纤维长度的混凝土进行立方体抗压强度试验和劈裂抗拉强度试验.结果表明,聚丙烯纤维混凝土立方体抗压强度和劈裂抗拉强度的预测模型与试验结果吻合程度较高;聚丙烯纤维混凝土拉压比在纤维掺量为0~0.1%之间递增,在纤维掺量为0.1%~0.25%之间递减;6 mm聚丙烯纤维混凝土拉压比与基准混凝土拉压比相比略有下降,12 mm聚丙烯纤维混凝土拉压比比基准混凝土提高了5.5%,聚丙烯纤维可以显著改善混凝土脆性破坏形态,提高混凝土韧性.

Experiment on tension-compression ratio of polypropylene fiber reinforced concrete

Aiming at the problem that the polypropylene fiber has certain influence on the strength and tension-compression ratio of concrete, the cube compressive strength test and splitting tensile strength test of concrete with different fiber contents and different fiber lengths were conducted with the standard test method. The results show that the prediction model for cube compressive strength and splitting tensile strength of polypropylene fiber reinforced concrete is well matched with the test results. The tension-compression ratio of polypropylene fiber reinforced concrete increases with increasing the fiber content from 0 to 0.1%, and decreases with increasing the fiber content from 0.1% to 0.25%. The tension-compression ratio of concrete with 6 mm polypropylene fiber is slightly lower than that of reference concrete, while the tension-compression ratio of concrete with 12 mm polypropylene fiber increases by 5.5% than that of reference concrete. The polypropylene fiber can effectively improve the brittle failure mode of concrete and enhance the toughness of concrete.