聚丙烯纤维长度和掺量对混凝土耐久性影响试验研究

Experimental study on the influence of polypropylene fiber length and content on concrete durability

研究了聚丙烯纤维掺量和长度对混凝土坍落度、抗压强度和抗氯离子侵蚀性能的影响。结果表明:随着聚丙烯纤维掺量的增加,混凝土的坍落度逐渐减小,抗压强度先提高后降低,氯离子扩散深度先减小后增大;聚丙烯纤维掺量为1.0%时,抗压强度最高,氯离子渗透深度最小,28 d抗压强度较基准组提高了12.9%、氯离子渗透深度较基准组减小了20.8%。随着聚丙烯纤维长度的增加,混凝土的坍落度和氯离子扩散深度逐渐增大,抗压强度逐渐降低。聚丙烯纤维的最佳掺量为1.0%、长度应小于16 mm。

The effect of polypropylene fiber content and its length on the slump,compressive strength and chloride corrosion resistance of concrete was studied.The results showed that:when the content of polypropylene fiber increases,the slump of concrete decreases,the compressive strength of concrete first increases and then decreases,the chloride diffusion depth of concrete first decreases and then increases.When the polypropylene fiber content is 1.0%,the compressive strength is the highest,and the depth of chloride ion penetration is the smallest.The 28-day compressive strength is 12.9% higher than that of the benchmark group,and the depth of chloride ion penetration is 20.8% lower than that of the benchmark group.With the increases of the length of polypropylene fiber,the slump and the chloride diffusion depth of concrete increase gradually,while the compressive strength of concrete decreases gradually.Therefore,it is suggested that the best content of polypropylene fiber in concrete is 1.0%,and the length of polypropylene fiber should be less than 16 mm.