Study And Application Of Bearing Capacity And Anchor Method Of The Frame Beam In The Negative Moment Region

Reinforced concrete frame structure is widely used in the industry and the civilconstruction field. Because of the change of the structural use function, the structuraldamage of natural disaster, worse durability of concrete and so on, the structural safety isinfluenced and the structure reliability is reduced. On the basis of this, reinforced concreteframe structure in the using must be strengthened. The study of anchor method of thereinforced concrete frame structure has significant engineering value and good socialbenefits for the safe use of the structure.In this paper, a method of bonded steel strengthening with sinuous type is designed,according to the mechanical feature of the reinforced concrete frame beam in the negativemoment region. First, the sinuous type steel plate is set in the bottom of the frame column,then the sinuous type steel plate and the strengthening steel are set on the face of thenegative moment region of the frame beam, and they are welded together. Then, thesinuous type steel plate, the strengthening steel and the frame beam are bonded togetherwith special structure adhesive. In order to verify the strengthen effect of the frame beamin the negative moment region, full-size cross-shaped feet frame beam-column joint isdesigned, finite-element analysis is applied to the steel and concrete separation model, thecode method is used, and the monotonic loading structure experiment is employed toframe beam-column joint specimen with the same size. The results of the numericalsimulation, the code and the testing are analyzed and the strengthen effect is discussed.The study shows that the ultimate bearing capacity and stiffness of the specimensstrengthened with the sinuous type steel plate are improved greatly comparing with thespecimens without strengthened. The finite-element analysis results show that the steelplate and the frame beam have good cooperation work performance and the sinuous typesteel plate have good strengthening effect. In addition, the strengthen method with sinuoustype steel plate is easier than the one that the code offers and the steel quantity is reduced.