纤维混凝土力学性能和抗冻性能试验研究

EXPERIMENTAL STUDY ON MECHANICAL PROPERTIES AND FROST RESISTANCE OF FIBER REINFORCED CONCRETE

试验研究了两种不同形态的聚丙烯纤维,即网状纤维和单丝纤维,其掺量分别在0.5 kg/m^(3)、1.0 m^(3)、1.5 kg/m^(3)的条件下,对C50混凝土力学性能和抗冻性能的影响。结果表明:当纤维掺量逐渐增加时,混凝土7 d强度出现先提升后降低的现象,但由于纤维的掺入,混凝土强度均大于基准组。混凝土28 d强度随着纤维掺量的增加,出现逐渐增大但增势变缓的现象,且网状纤维对力学性能的提升作用更加明显。在抗冻性能方面,相比单丝纤维,网状纤维混凝土质量损失率和相对弹性模量损失均较小,变化速率更缓慢。

Two different types of polypropylene fiber were studied,namely,reticular fibers and monofilament fibers.Their influence on the mechanical properties and frost resistance of C50 concrete was tested,with a content of 0.5 kg/m^(3),1.0 kg/m^(3) and 1.5 kg/m^(3),respectively.Results showed that when the fiber content increased gradually,the 7 d strength of concrete first rose and then dropped.However,the strength of concrete containing fibers is higher than that of the control group.With the fiber content increasing,the 28 d strength of concrete grew gradually but its growth slowed down.In addition,reticular fibers have more prominent effect on the mechanical properties of concrete.In terms of frost resistance,the concrete containing reticular fibers has less loss in mass and relative elastic modulus than monofilament fibers.The mass and relative elastic modulus of concrete containing reticular fibers change less slowly than that containing monofilament fibers.