聚丙烯纤维高性能混凝土抗冲击性能研究

Study on impact resistance of polypropylene fiber high performance concrete

为了更加科学合理地对高性能混凝土的抗冲击性能进行评价,研究聚丙烯纤维混凝土抗冲击性能,将标准立方体抗压试件切割成厚度为30、40、50 mm的混凝土板,利用自制的落锤冲击试验装置,得到了聚丙烯纤维高性能混凝土板在1.2 kg钢球作用下的初裂次数和终裂次数,并测量了试件遭受冲击荷载后的裂缝长度、宽度和深度,最后对试验结果进行了研究和回归分析。结果表明,聚丙烯纤维能够增强混凝土的冲击韧性,高性能混凝土的抗裂能力与试样厚度和聚丙烯纤维掺量均呈一次线性正相关关系,试样厚度的增加能够显著改善高性能混凝土的抗初裂能力和抗冲击强度保留率。

In order to evaluate the impact resistance of high performance concrete more scientifically and reasonably,the impact resistance of polypropylene fiber concrete is studied.By cutting the standard cube compressive specimens into concrete slabs of thickness 30,40 and 50 mm.The service crack number and ultimate crack number of polypropylene fiber reinforced high performance concrete slab under the impact blow of 1.2 kg steel ball were obtained by means of self-made drop weight impact test device.The crack length,width and depth of specimens after impact loading are measured.Finally,the experimental results were studied and regression analysis was conducted.The results show that polypropylene fiber can improve the impact resistence of concrete.The crack resistance of the high performance concrete has a linear positive correlation with the thickness of the sample and the amount of polypropylene fiber.The increase of specimen thickness can significantly improve the impact residual strength ratio and service crack resistance.