中文摘要：

为了探讨解决现浇混凝土楼板中长期非荷载抗裂性的难题，对聚丙烯纤维混凝土的平板进行了中长期抗裂试验，研究聚丙烯纤维对提高混凝土中长期抗裂、抗渗等耐久性能的效果和机理，通过实际工程的应用进一步验证了聚丙烯纤维对混凝土裂缝有较好的抑制作用。研究结果表明，聚丙烯纤维对混凝土中长期裂缝有较好的抑制作用；聚丙烯纤维能有效改善混凝土的抗渗性能；聚丙烯纤维使混凝土的抗拉强度、拉伸极限应变、临界断裂时的最大裂缝宽度增加。使用聚丙烯纤维混凝土楼板具有较显著的经济效益和社会效益。

英文摘要：

In order to find a solution to the problem of mid-long term non-load crack resistance of cast-in-place concrete floor and study the effects and formation mechanism of concrete mid-long term crack and permeation resistance improved by the polypropylene fiber, the experimental analysis on slab mid-long crack resistance of polypropylene fiber reinforced concrete is carried out. The application of the research findings to practical engineering has proved the outstanding crack resistance effects of the polypropylene fiber. The research results of the paper show that polypropylene fiber has better inhibition action on concrete mid-long term cracking and greater effect to improving concrete mid-long term crack resistance; polypropylene fiber can effectively improve concrete permeation resistance; polypropylene fiber enhances concrete tensile strength, limit tensile stain and maximum crack width of critical fracture. The application of polypropylene fiber reinforced concrete floor has comparatively remarkable economic and social benefits.