纤维混凝土早期抗裂及力学性能试验研究

Test of the Early Crack Resistance and Mechanical Properties of Fiber Reinforced Concrete

选取了聚丙烯纤维、纤维素纤维等6种工程纤维,开展纤维混凝土早期抗裂及力学性能试验,研究分析纤维品种及龄期对混凝土早期抗裂性能、抗压强度、劈裂强度及抗折强度的影响.试验结果表明:纤维的掺入能够有效提高混凝土早期抗裂性能,减轻甚至消除混凝土早期裂缝的产生和发展.本次试验研究中,聚丙烯纤维混凝土的早期抗裂性能最好.无论采用何种纤维,混凝土的抗压强度、劈裂强度和抗折强度均有不同程度的提高,提高幅度与纤维几何尺寸以及物理力学性能有关.其中,聚乙烯醇纤维提高混凝土抗压强度的效果最为显著,而纤维素纤维提高混凝土劈裂强度和抗折强度的效果最佳.

The test of early crack resistance and mechanical properties of fiber reinforced concrete were conducted to analyze the effects of fiber varieties and ages on the early crack resistance compressive strength,splitting tensile strength,and flexural strength of fiber reinforced concrete.The results showed that fiber can improve the early cracking property of concrete,reduce or even eliminate the generation and development of the early crack of concrete.The early cracking property of polypropylene fiber reinforced concrete was best.Whatever the fiber,the concrete compressive strength,the splitting strength and the flexural strength were improved in different degrees,while the increased degree was associated with the geometric and mechanical properties of fiber.Polyvinyl alcohol fiber could significantly enhance the compressive strength of concrete,while cellulose fiber could considerably improve the splitting strength and flexural strength of concrete.