体外配置CFRP预应力筋混凝土箱梁受力性能试验研究

制作了体外配置碳纤维(CFRP)筋预应力混凝土薄壁箱梁模型,对模型箱梁从CFRP预应力筋张拉、加载至混凝土开裂这一过程进行了试验研究,研究了预应力损失和均布荷载作用下箱梁跨中截面应力-应变分布规律、受压翼缘有效分布宽度系数、跨中挠度、抗裂性能以及CFRP体外预应力筋的应力变化情况,试验表明该箱梁具有良好的抗裂性能与变形性能,混凝土开裂引起顶板受压翼缘有效分布宽度系数增加小于5%。该研究为CFRP体外预应力筋在混凝土薄壁箱梁中的推广应用提供了可靠的试验依据。

Experimental Study on Behaviour of Concrete Box Girder Prestressed with External CFRP Tendons

A concrete thin-walled box girde with externally prestressed CFRP tendons has been made,and tested in the course of CFRP tendons tensing until concrete cracking.Prestressing loss and some behaviors under uniform load such as stress and strain distribution,effective width coefficient of compressive top flange,deflection,crack patterns at mid-span,and stress variety of CFRP tendons have been studied.Experiments show that the box girder perform well against cracking and deformation,with effective width coefficient of compressive top flange increased byless than 5% due to concrete cracking.The reliable experimental basis will be helpful to the application of externally prestressed CFRP tendons in concrete box girder.