中文摘要：

通过14组56根带切口自密实混凝土梁三点弯曲试验,研究不同掺量的钢纤维、聚丙烯腈纤维、钢纤维与聚丙烯腈纤维组成的混杂纤维对自密实混凝土断裂能的影响规律。试验中制作了未掺纤维且强度相近的自密实混凝土伴随试件,用以对比并计算断裂能增益比。结果表明：钢纤维能显著提高自密实混凝土的断裂能,随着钢纤维掺量的增加,其断裂能呈线性增加;聚丙烯腈纤维有利于自密实混凝土断裂能的提高,但影响较小,且非线性增加;在钢纤维体积率不变情况下,聚丙烯腈纤维有利于混杂纤维自密实混凝土断裂能的提高,但也非线性增加。在分析试验结果的基础上,提出了以混凝土抗压强度、骨料最大粒径、纤维影响系数为主要因素的纤维自密实混凝土断裂能计算模型,经过对比表明,计算模型具有良好精度。

英文摘要：

On the base of three-point bending experiments of a total of 56 specimens in 14 groups,the influencing rules of steel fiber,polyacrylonitrile（PAN） fiber,and hybrid steel/PAN（S/P） fiber on the fracture energy of self-compacting concrete（SCC） are investigated in this paper.The relative SCC specimens without any fiber were tested and compared with the fiber reinforced SCC to accumulate the increment ratio of fracture energy.The results show that the fracture energy of SCC increases obvious linearly with the increment of steel fiber.PAN fiber tends to be nonlinearly improves the fracture energy of SCC,but not so obviously as steel fiber.As to hybrid S/P fiber reinforced SCC having a constant content of steel fiber,the fracture energy increases nonlinearly with the increment of PAN fiber.On the base of experimental results,a calculation model of fiber reinforced SCC is presented with compressing strength,maximum size of aggregate and influencing coefficient as main factors.The calculating results of suggested model are compared with experimental results and excellent agreement is found