玄武岩纤维布加固混凝土梁的抗弯疲劳性能试验

Study on Fatigue Performance of Reinforced Concrete Beams Strengthened with BFRP Sheet

通过2根玄武岩纤维布加固的钢筋混凝土梁和1根普通钢筋混凝土梁的弯曲疲劳性能试验研究,分析玄武岩纤维布对加固梁抗弯疲劳性能的影响.试验结果表明,采用玄武岩纤维布进行加固后,梁的抗疲劳性能得到极大改善;粘贴1层和2层玄武岩纤维布后,钢筋混凝土梁的疲劳寿命分别提高了66%和235%,50万次时,其疲劳变形分别减小了26.04%和35.40%.在纤维布与混凝土粘结可靠的情况下,若梁的配筋率不超过2.5%,加固梁发生钢筋疲劳断裂破坏的可能性极大.

The bending fatigue test on one ordinary reinforced concrete beam and two reinforced concrete beams strengthened with basalt fiber polymer sheets（BFRP） is carried out,and the flexural fatigue performance of the reinforced concrete beams strengthened with BFRP is analyzed.The experimental results show that BFRP improves greatly the anti-fatigue performance of the beam.Pasting one layer or two layers of BFRP,the fatigue life of reinforced concrete beams increases by 66% and 235%;the fatigue deformation decreases by 26.04% and 35.40% for 500 thousand cycles.On condition of reliable bound between BFRP and concrete,if,the fatigue fracture of steel bars will occur greatly possibly for the reinforcement ratio less than 2.5%.