Experimental Research of Rc Recycled Concrete Beams Strengthened with CFRP Bonded by Structural Adhesives
|Course||Bridge and Tunnel Engineering|
|Keywords||Recycled concrete beams CFRP reinforced Bendingperformance Capacity Damaging form Deflection Cracks|
With the rapid development of urbanization and economic of our country，theproblem which is the numerous demand of the concrete and the construction wastelarge number generated, has become an important challenge we must face in societytoday. How to turn this waste resource to treasure, to make a good use of the greatresource and solve the problems of demand and environmental, so that make theresearch of the recycled aggregate concrete to a research focus in the concrete areas.Based on the research of recycled aggregate concrete and recycled concretebeams，this thesis conducted a pilot study of CFRP reinforced recycled concretebeams. First the test with ten recycled concrete beams and two concrete beams ofstrength C35by the processing of pre-crack and reinforcement by CFRP. By the staticloading test of third point, record and observe the flexural capacity, mid-spandisplacement, damage form and the fissure condition and width and so on of theCFRP reinforcement by beams. Analysis the influence of recycled aggregate dosage,CFRP reinforcement rate and other factors of the flexural performance of the CFRPreinforced recycled concrete beams.The recycled concrete beam which reinforced used the CFRP, it’s concreteaverage strain changes of the cross-section are still comply with the plane sectionassumption requirements. After using the CFRP reinforced the recycled aggregateconcrete beams, the flexural capacity of the test beams have a significantlyimprovement. When the recycled coarse aggregate quantity is low (0-70%), theimprovement degrees of the flexural capacity are increasing with the increasing of therecycled aggregate quantity increases；When the recycled coarse aggregate quantity is100%or completely recycled aggregate, the improvement degrees of the bearingcapacity are decreased. By using CFRP reinforced the recycled concrete beams，thebending stiffness of the beams is increased, but with the recycled aggregate increase， the bending stiffness’ improvement degrees are reduced accordingly. With the samerecycled aggregate quantity test beams, which reinforced two layers of CFRP,it’scracks total number are more than the one reinforced a layer of CFRP. The increase inthe amount of the CFRP (ie increase the reinforcement rate) can further improve theflexural capacity of the beams, but also changes the failure modes of the beams, thiscorruption form did not fully play the high tensile strength of the CFRP.