外贴CFRP板加固锈蚀钢板疲劳性能试验研究

Experimental study on the fatigue performance of corroded steel plate strengthened with externally bonded CFRP plates

为研究外贴CFRP板对锈蚀钢板疲劳性能的影响,开展16个CFRP板加固锈蚀钢板试件的疲劳拉伸试验,研究锈蚀程度、CFRP刚度、CFRP预应力度、端部锚固及疲劳应力幅对CFRP板加固锈蚀钢板疲劳破坏模式、疲劳寿命及裂纹扩展规律的影响。研究结果表明,外贴CFRP板可以显著提升锈蚀钢板疲劳寿命,对质量损失率为9.38%、13.39%、16.61%及21.24%的锈蚀钢板,端部锚固条件下双面粘贴CFRP板加固试件疲劳寿命相对于未加固试件分别提高了18.4倍、9.3倍、8.9倍及11.4倍;加固方式对疲劳加固效果影响显著,端部锚固可以有效延缓黏结界面失效,增大CFRP板加固刚度或采用预应力加固均可显著降低裂纹扩展速率。

In order to investigate the fatigue performance of corroded steel plate strengthened with externally bonded CFRP plates,the fatigue tensile tests on sixteen corroded steel plates strengthened with CFRP plates were carried out.The effects of corrosion duration,CFRP stiffness,CFRP prestressing level,end anchorage,and fatigue stress amplitude on the fatigue performance,including fatigue failure mode,fatigue life and crack propagation,of the reinforced steel plates were studied.Test results show that externally bonded CFRP plates may significantly improve the fatigue life of the corroded steel plates,and for the corroded steel plates with the corrosion rate of 9.38%,13.39%,16.61%and 21.24%,the fatigue life of the reinforced specimens with double-sided patched CFRP plates and end anchorage may be increased by the factors of 18.4,9.3,8.9 and 11.4 respectively,compared with the unreinforced specimens.Tests results also indicate that the reinforcement configurations has a significant impact on the fatigue strengthening effect,the failure of bonding interface may be effectively delayed by end anchorage,and the crack propagation rate can be significantly reduced by increasing the stiffness of CFRP plates or adopting the prestressing.