This paper discusses the synergetic effect of ground granulated blast-furnace slag and hooked-end steel fibers on the fresh, mechanical, and microstructural properties of steel fiber-reinforced self-compacting concrete containing fly ash. A total of 12 mixtures were prepared. Hooked-end steel fibers at four different volume fractions (0%, 0.3%, 0.6%, and 0.9%) were applied as reinforcement, while the slag contents (0%, 10%, and 30% of the cement weight) was varied; the fly ash content (20% of the cement weight) was kept constant to partially replace Portland cement. The properties of plain and steel fiber reinforced self-compacting concrete mixtures were tested and compared. The experimental results showed that substituting cement with 10% slag effectively enhanced the workability of the fresh concrete, while replacing cement by 30% slag reduced the passing ability and filling ability. The addition of fibers reduced the workability of self-compacting concrete. Furthermore, the addition of slag can compensate the effect on the fresh properties caused by fibers. With respect to the mechanical properties, the synergistic effect of slag and hooked-end steel fibers improved the compressive strength, tensile strength and flexural strength. At the microstructural level, blast-furnace slag can enhance the bonding performance of the fiber-matrix interface, thereby improving the mechanical properties.

中文翻译：

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磨碎粒状高炉矿渣与钩端钢纤维对钢纤维自密实混凝土各项性能的协同作用

本文讨论了磨碎的粒状高炉矿渣和钩端钢纤维对含粉煤灰钢纤维增强自密实混凝土的新鲜、力学和微观结构性能的协同作用。共制备了 12 种混合物。采用四种不同体积分数（0%、0.3%、0.6% 和 0.9%）的钩端钢纤维作为增强材料，同时改变矿渣含量（水泥重量的 0%、10% 和 30%） ; 粉煤灰含量（水泥重量的 20%）保持不变，以部分替代波特兰水泥。对普通和钢纤维增强自密实混凝土混合物的性能进行了测试和比较。试验结果表明，用10%矿渣代替水泥有效提高了新拌混凝土的和易性，而用30%的矿渣代替水泥则降低了通过能力和充填能力。纤维的添加降低了自密实混凝土的可加工性。此外，矿渣的添加可以补偿纤维对新鲜性能的影响。在力学性能方面，矿渣和钩端钢纤维的协同作用提高了抗压强度、抗拉强度和抗弯强度。在微观结构层面，高炉渣可以增强纤维-基体界面的结合性能，从而提高力学性能。矿渣和钩端钢纤维的协同作用提高了抗压强度、抗拉强度和抗弯强度。在微观结构层面，高炉渣可以增强纤维-基体界面的结合性能，从而提高力学性能。矿渣和钩端钢纤维的协同作用提高了抗压强度、抗拉强度和抗弯强度。在微观结构层面，高炉渣可以增强纤维-基体界面的结合性能，从而提高力学性能。