吉林建筑大学学报

钢纤维作为一种抗拉能力较强且与混凝土黏结能力较好的材料，随着钢纤维在活性粉末混凝土(RPC)中体积掺量的增加，混凝土成本快速增加，而强度、韧性等增速逐渐降低。通过固定钢纤维体积掺量，改变钢纤维的种类与混掺比例，设计并制作了22组标准养护条件下的RPC试件，通过试验分析抗压强度、轴心抗压强度、劈裂抗拉强度、抗折强度和弯曲韧性等力学指标，研究多种纤维长度、纤维形状和掺杂比例对RPC力学性能的影响，并寻找较优的钢纤维混掺方案。结果表明：3%钢纤维体积掺量下，13 mm端钩型钢纤维与20 mm端钩型钢纤维混掺比例为1∶3时，RPC各力学性能最好。与仅使用13 mm平直型钢纤维的RPC试件相比，该混掺比例的RPC试件抗压强度提升了24.78%。劈裂抗拉强度提升了61.43%，抗折强度提升了236.43%，弯曲韧性I₁₀提升了283.64%，验证了采用混杂不同种类的钢纤维以增强活性粉末混凝土力学特性的方法之可行性。

Steel fibers, known for their strong tensile properties and excellent bonding ability with concrete, lead to a rapid increase in concrete costs as the volume fraction of steel fibers in reactive powder concrete(RPC) increases. However, the rate of improvement in strength, toughness, and other properties gradually decreases. By fixing the volume fraction of steel fibers and altering the types and hybrid ratios of steel fibers, 22 sets of RPC specimens under standard curing conditions were designed and fabricated.Experimental analyses were conducted on mechanical indicators such as compressive strength, axial compressive strength, splitting tensile strength, flexural strength, and bending toughness. The research aimed to investigate the impact of various fiber lengths, fiber shapes, and hybrid ratios on the mechanical properties of RPC, and to identify an optimal hybrid scheme for steel fibers. The results show that with a 3%steel fiber volume fraction, the mechanical properties of RPC are optimal when the mixing ratio of 13 mm hooked-end steel fibers to 20mm hooked-end steel fibers is 1:3. Compared to RPC specimens using only 13 mm straight steel fibers, RPC with this mixing ratio exhibits a 24.78% increase in compressive strength, a 61.43%increase in splitting tensile strength, a 236.43% increase in flexural strength, and a 283.64% increase in bending toughness(I₁₀). This confirms the feasibility of utilizing hybridized heterogeneous steel fibers to enhance the mechanical properties of RPC.