GFRP布加固钢筋混凝土短梁受弯性能试验研究

Experimental study on flexural performance of reinforced concrete short beams strengthened by GFRP sheets

对3根玻璃纤维复合材料(Glass Fiber Reinforced Polymer,简称GFRP)布加固的钢筋混凝土短梁进行了受弯试验,研究了GFRP布层数对加固短梁受弯性能的影响。试验结果表明:跨高比为4的加固短梁和普通短梁均较符合平截面假定;随GFRP布层数的增加,试件的开裂、屈服和极限荷载均增加,加固短梁的破坏逐渐向超筋梁特征发展;钢筋屈服后,GFRP布可以显著提高加固短梁的抗弯刚度,表明GFRP布在此阶段发挥的作用最大;普通短梁的延性最好,随GFRP布层数的增加,加固短梁的延性逐渐降低。

Through the bending tests of three short beams strengthened by GFRP sheets, the effect of the number of layers of GFRP sheets on the bending properties of strengthened short beams was studied. The results show that the strengthened short beams and ordinary short beams with a span-to-height ratio of 4 are more in line with the assumption of flat section. With the increase of fiber layers, the cracking, yield and ultimate load of the specimens increase, and the damage of the strengthened short beams gradually develops to the characteristics of over-reinforced beams. The flexural stiffness of strengthened short beams can be significantly improved with the increase of fiber sheets after the steel bar yields, which indicates that fiber cloth plays the most important role at this stage. The ductility of ordinary short beams is the best. With the increase of the number of layers of fiber sheets, the ductility of strengthened short beams decreases gradually.