纤维混凝土在盐冻作用下的耐久性研究

RESEARCH ON THE DURABILITY OF POLYPROPYLENE FIBER CONCRETE UNDER FREEZE-THAW DAMAGE

以不同纤维掺量的聚丙烯纤维混凝土为研究对象,采用快速冻融法模拟自然盐冻,研究聚丙烯纤维混凝土的抗盐冻性能和氯离子在盐冻作用下的迁移。结果表明:混凝土的质量损失率和相对动弹性模量损失随纤维掺量的增大而减少,氯离子浓度在靠近试件表面处富集,掺量为0.1%的纤维混凝土能有效地延缓氯离子的迁移,大掺量纤维的掺入会降低混凝土内部的密实度,但在盐冻过程中可以延缓裂缝的发展。

In order to study the Cl-migration under freeze-thaw cycle and the freeze-deicing salt scaling resistance of polypropylene fiber concrete with different volume,indoor artificial method was used to simulate freeze-thaw cycle.The results indicated that the scaled mass and relative dynamic modulus of elasticity loss decrease with the volume of fiber increasing,Cl-concentration had a enrichment near the sample surface,adding 0.1% PPF into concrete had the prefect resistance of deicer-frost scaling.More fibers could delay the development of cracks,but that would reduce the inner density of concrete.