CFRP筋加固混凝土梁抗弯性能试验研究

Experimental Study on Flexural Behavior of Concrete Beams Strengthened with CFRP Bars

文章研究了碳纤维筋和预应力水平对加固钢筋混凝土梁的抗弯承载力、挠度和裂缝宽度的影响,并分析了相应的作用机理.结果表明,控制应力为50%、受拉钢筋为2C16的JGL5试件的开裂荷载、屈服荷载和极限荷载最大,具有最佳的加固效果.在相同的裂缝宽度下,6组混凝土梁试件对应的荷载明显不同,对应荷载从小到大的顺序为:L1<JGL1<JGL2<JGL3<JGL4<JGL5,预应力对混凝土梁试件的裂缝形成有抑制作用,且在相同荷载作用下,添加碳纤维筋的混凝土梁对裂缝的抑制效果要明显优于未加固的混凝土梁.在相同荷载下,未添加碳纤维筋的混凝土梁的挠度都大于添加碳纤维筋的混凝土梁,即添加碳纤维筋有助于提高加固混凝土梁构件的刚度;JGL5试件的挠度值较小,加固效果要优于其他试件.

The effects of CFRP and prestressed level on flexural capacity,deflection and crack width of reinforced concrete beams are studied,and the corresponding mechanism is analyzed.The results show that the cracking load,yield load and ultimate load of JGL5 with 50%control stress and the tensile reinforcement is 2C16 is the largest,and it has the best reinforcement effect.Under the same crack width,the corresponding loads of six groups of concrete beam specimens are significantly different.The sequence of corresponding loads from small to large should be L1<JGL1<JGL2<JGL3<JGL4<JGL5.Prestress has a restraining effect on the crack formation of concrete beam specimens,and under the same load,the restraining effect of adding carbon fiber reinforced concrete beams on cracks is significantly better than that of unreinforced concrete beams.Under the same load,the interference of concrete beams without adding CFRP is more than that of concrete beams with adding CFRP,that is to say,adding CFRP will help to improve the rigidity of reinforced concrete beams;the interference value of JGL5 specimens is smaller,and the reinforcement effect is better than other specimens.