低周反复荷载下混杂纤维混凝土柱抗剪承载力研究

Shear Capacity Research of Hybrid Fiber Reinforced Concrete Columns under Low Reversed Cyclic Loading

通过低周反复荷载试验,研究了钢纤维混凝土、钢-聚丙烯混杂纤维混凝土柱的破坏现象、破坏形态,分析了纤维掺量对抗剪承载力的影响规律;利用桁架+拱的模型理论推导了钢纤维混凝土柱在低周反复荷载作用下的抗剪承载力计算公式,并将试验值与理论计算值进行了比较。结果表明:钢纤维混凝土柱呈现弯曲破坏、钢-聚丙烯混杂纤维混凝土柱呈现弯剪破坏;掺量为1.0%、1.5%、2.0%的三种钢纤维混凝土柱的抗剪承载力比基准混凝土分别提高14.10%、19.87%和12.18%;钢纤维掺量为1.0%、1.5%、2.0%,聚丙烯纤维掺量均为0.1%的三种混杂纤维混凝土柱的抗剪承载力比基准混凝土分别提高19.23%、23.72%、16.03%;抗剪承载力试验值与理论推导计算值有较好的一致性和适用性。

Through low reversed cyclic loading test,the damage phenomenon,failure mode of steel fiber reinforced concrete and steel-polypropylene hybrid fiber reinforced concrete columns were studied,the effect of fiber content on shear capacity was analyzed. Based on the theory of truss-arch model,the formula for calculating shear capacity of steel fiber reinforced concrete columns under low cyclic loading was derived,the experimental and theoretical values were compared. The results show that the steel fiber reinforced concrete column shows bending failure and the steel-polypropylene hybrid fiber reinforced concrete column shows bending and shearing failure. The shear capacity of steel fiber reinforced concrete columns with steel fiber content of 1.0%,1.5% and 2.0% are 14.10%,19.87% and 12.18% higher than that of ordinary reference concrete respectively. The shear capacity of hybrid fiber reinforced concrete columns with steel fiber content of 1.0%,1.5% and 2.0%,and polypropylene fiber content of 0.1%,are 19.23%,23.72% and 16.03% higher than that of ordinary reference concrete respectively. The experimental value of shear capacity has good consistency and applicability with the calculated value.