不同加固方式对钢筋混凝土梁抗弯性能的影响

Effect of Different Reinforcement Methods on the Bending Performance of Reinforced Concrete Beams

以我国某条高速公路的改扩建工程中的预应力钢筋混凝土梁为原型,通过缩尺模型,设计了3根试验梁,主要研究了CFRP布加固法和预应力钢绞线加固法对桥梁结构弯曲性能的影响,分析了试验梁极限承载力的变化,梁体的挠度,混凝土、钢筋及加固材料的应变,裂缝数量及发展情况等。试验结果显示:CFRP布加固法和预应力钢绞线加固法均能有效提高梁体的承载能力;CFRP布加固法通过分散受拉区混凝土所受的拉应力,限制混凝土裂缝的发展;预应力钢绞线加固法约束梁体弯曲变形的效果非常明显,可以有效减小梁体的挠度。

3 test beams through the scale model which was based on the prestressed reinforced concrete beam in the construction of a highway in China was designed. The effects of CFRP（ Carbon Fiber Reinforced Plastics） sheet reinforcement and prestressed steel strand reinforcement on the bending performance of bridge were studied,through analyzing the changes of the limit bearing capacity of girders,the deflection of the beam body,the strain of concrete,reinforcement and reinforcing materials,the number and development of cracks. The results show that： CFRP sheets reinforcement and prestressed steel strand reinforcement can improve the bearing capacity of beams effectively; CFRP sheets reinforcement can limit the development of cracks by disperse the tensile stress of concrete. Prestressed steel strand reinforcement can bind the bending of the beam obviously,as well as reduce the deflection effectively.