基于有效惯性矩的钢纤维高强混凝土梁刚度计算方法

Calculation Method for Stiffness of Steel Fiber Reinforced High-strength Concrete Beams Based on Effective Moment of Inertia

在13根钢纤维高强混凝土梁等幅疲劳试验基础上，探讨了等效应力比、铜纤维类型、钢纤维体积率、铜纤维掺入范围和混凝土强度对钢纤维高强混凝土梁挠度和刚度的影响，建立了基于有效惯性矩的钢纤维高强混凝土梁刚度计算模型及公式。结果表明：在高强混凝土梁中掺入钢纤维提高了梁的截面刚度，使疲劳荷载作用下高强混凝土梁跨中挠度减小15％～61％；基于有效惯性矩的钢纤维高强混凝土梁挠度和刚度计算结果与试验结果吻合较好。

Based on the constant amplitude fatigue tests on 13 steel fiber reinforced high-strength concrete beams, the influences of equivalent stress, steel fiber types and volume fractions, depth of steel fiber layer and concrete strength on the deflection and stiffness of steel fiber reinforced high-strength concrete beams were investigated. The calculation method and formulas for stiffness of steel fiber reinforced high strength concrete beams were put forward based on the effective moment ot7 inertia. The results show that adding steel fiber into the high-strength concrete beam can increase its section stiffness effectively, and the deflection of steel fiber reinforced high-strength concrete beams decreases by 15%-61 % under fatigue load. The calculated values of deflection and stiffness based on effective moment of inertia have good agreement with test results