配置碳纤维预应力筋的钢纤维活性粉末混凝土无腹筋梁疲劳性能试验研究

对6根仅配置纵向CFRP预应力筋的钢纤维活性粉末混凝土（RPC）无腹筋梁试件进行了静力和疲劳试验，研究了RPC钢纤维含量、疲劳荷载水平、加载方式等参数对其疲劳性能的影响。结果表明：疲劳荷载作用下梁试件发生剪切破坏；无论是承受静力荷载还是疲劳荷载的梁试件，都不宜过高估计钢纤维的作用而取消抗剪腹筋；提高钢纤维含量可以显著改善梁试件的疲劳性能，钢纤维含量为3%的CFRP预应力筋RPC无腹筋梁，若RPC的主拉应力小于其抗拉强度的50%，可免于疲劳破坏；经回归分析，给出了试验梁的刚度退化方程及RPC主拉应力与疲劳寿命关系方程。

Experimental study on fatigue properties of CFRP prestressed RPC beams without stirrups

Through the fatigue and static experiments on six CFRP prestressed RPC beams without stirrups, the effects of steel fiber content, fatigue load, loading modes and other parameters on the fatigue behavior were investigated in detail. It shows that the beams without stirrups are prone to shear failure under fatigue loads. The stirrups in the beams should not be cancelled by overestimating the role of steel fiber. The fatigue behavior of the beams can be greatly enhanced by improving the steel fiber content. The CFRP prestressed RPC beam can avoid fatigue damage if the principal tensile stress of the RPC is less than 50% of its tensile strength. The stiffness degradation equation and correlation of principal tension stress of RPC versus fatigue life was proposed through regression analysis.