聚丙烯纤维混凝土早期开裂敏感性的研究

Research on Early Cracking Sensitivity of Polypropylene Fiber Reinforced Concrete

针对荆岳长江公路大桥塔座及下塔柱对混凝土抗开裂性能的要求,采用温度应力试验机研究了聚丙烯纤维对混凝土早期开裂敏感性的影响,并对其温度应力的发展过程进行分析。结果表明:聚丙烯纤维的掺入能较大地提高混凝土的抗拉强度,抑制混凝土的早期收缩,提高混凝土的抗裂能力,但其温度和应力的发展速率增大,对早期养护提出了严格要求。

According to the anti - cracking requirements of pillar base and lower pylon column of Jingyue Yangtze River Highway Bridge, the influence of polypropylene fiber on early cracking sensitivity of reinforced concrete was studied by using temperature-stress test machine. And the development process of temperature and stress was also analyzed. The results indicated that the polypropylene fiber could greatly improved the tensile strength of concrete, restrained early shrinkage effectively and improved the anti-cracking ability. But its development rate of temperature and stress increased rapidly, which proposed strict requirements of early curing.