预应力CFRP板加固在役梁桥性能评估

Performance evaluation of in-service beam bridge strengthened by prestressed CFRP plates

为评估预应力碳纤维增强复合材料(carbon fiber reinforced polymer/plastic, CFRP)板对在役预应力混凝土连续空心板桥的加固效果,采用数值模拟和荷载试验结合的方式,研究预应力CFRP板的加固机理和加固效果。结果表明:预应力CFRP板加固在役预应力混凝土连续空心板桥能改善梁体开裂后的下挠状态,抑制裂缝扩展,提高结构耐久性,但对开裂结构本身的刚度提高效果非常有限;该加固方式不适用于开裂梁体在正常使用状态下的刚度提升需求。

To evaluate the strengthening effect of prestressed carbon fiber reinforced polymer(CFRP)plates on an in-service prestressed concrete continuous hollow slab bridge,the mechanism and effectiveness of prestressed CFRP plate strengthening an in-service prestressed concrete continuous hollow slab bridge are studied using a combination of numerical simulation and load testing.The results indicate that prestressed CFRP plate strengthening can improve the deflection state of the beam after cracking,suppress crack propagation,enhance structural durability,but the effect on increasing the stiffness of the cracked structure itself is very limited,and this strengthening method is not suitable for the stiffness enhancement requirements of cracked beams in normal service conditions.The theoretical research and results can provide a basis for the reinforcement design of similar structures and decision-making for the expansion and reconstruction of highways.