粘钢加固及粘钢板与CFRP复合加固损伤RC板抗弯试验研究

Experimental Study on Flexural Behavior of Damaged RC Slabs Strengthened with Bonded Steel and Combination of Steel Plates and CFRP

对7块使用近60年的RC桥面板采用粘贴钢板加固法及粘贴钢板与CFRP复合加固法加固后进行抗弯性能试验研究.试验对比研究了不同加固方式下试验板的承载力、刚度、裂缝、应变以及破坏形态等变化规律.试验结果表明:两种加固方法均能有效提高试验板的抗弯性能;粘贴2 mm、4 mm和6 mm厚钢板试件的承载力分别提高52.5%、126.0%和162.5%,复合加固试验板承载力分别提高87.0%、148.0%和158.5%;采用钢板和CFRP复合加固既有损伤受弯构件时,CFRP的加固作用能得到充分的发挥;对于粘贴钢板加固法,现行规范和规程可用于既有损伤RC板的抗弯承载力计算;运用本文提出的考虑损伤影响的粘钢加固及粘钢板与CFRP复合加固既有损伤构件抗弯承载力计算方法所得的计算值与试验值吻合较好.

Seven RC bridge decks that have been used for nearly 60 years were tested on flexural behavior after being strengthened with steel plates and composite steel plates and CFRP.The flexural capacity,stiffness,cracks and strain,as well as the failure modes of the test slabs under different strengthening methods were compared and ana-lyzed.The results show that both steel-bonded reinforcement and composite reinforcement of steel plate and CFRP can effectively improve the flexural behavior of the test slabs.The flexural capacity of the specimens with 2 mm,4 mm,and 6 mm thick steel plates is increased by 52.5%,126.0%and 162.5%,respectively.Correspondingly,the flexural capacity of the specimens with composite strengthened slabs is increased by 87.0%,148.0%and 158.5%,respectively.When the steel plates and CFRP were combined to strengthen the existing damaged flexural members,the strengthening effect of CFRP can be brought into full play.The current codes and regulations for steel-bonded reinforcement can be used for the calculation of flexural capacity of existing damaged RC slabs.A calculation method for flexural capacity of existing damaged members strengthened by steel plates and composite steel plates and CFRP considering damage effect is proposed,and the calculated results agree well with the experimental results.