The Flexural Capacity Study On RC Beams Strengthened By Steel Plate-Concrete Composite Based On Secondary Load

Due to the lower design standard, improper construction as well as the change offunction, the bridge structures need to be strengthened to improve the bearing capacityand prolong the service life. Steel-concrete composite reinforcement technique is a newmethod of reinforcement based on the existing method and the steel-concrete compositeconcrete structure, and this reinforcement method synthesizes the advantages ofbonding steel plates and section enlargement method. Due to the structure, load typesand usage requirements and other conditions, reinforcement structures are often in thetwo state of stress. Reinforcement in the actual project are often not to be completelyuninstall, resulting in the stress as well as strain of strengthening plate relative to theinitial structure. Actually, it’s overestimate the bearing capacity of strengthenedmembers without considering the two force in the actual reinforcement.In order to study the flexural performance of reinforced structure under theinfluence of the two forces. This paper intends to treat steel-concrete compositereinforced concrete beam as the research object, considering the secondary loadconditions, analysis of the development of steel-concrete composite reinforcedconcrete flexural capacity systemly through theoretical analysis and the use of nonlinearfinite element method, separately from the initial bending moment, section height ofreinforcement, the amount of reinforcement plate, the reinforcement ratio and so on.According to the finite element software ANSYS, it suggests a new steel-concretecomposite reinforcement method of finite element model of reinforced concrete with theexisting reinforcement method and steel-concrete structure on the basis of finiteelement theory. And combined with relevant theory of reinforced concrete, the finiteelement model of reinforced concrete beam strengthened by steel-concrete was build inorder to analysis reinforcement effect of ultimate load bending capacity of the numericalsimulation of composite reinforced beam before and after reinforcement throughdifferent parameters considering the nonlinear of concrete, then,a practical, simplecalculation method of beam reinforcement was inferred. The results of theoreticalcalculation and finite element calculation were compared with in good agreement,which can be a reference for practical engineering application use. Because of thereinforcement plate is suppressed by the development of crack and increasingreinforcement structure section, the bearing capacity of the strengthened structure can be significantly improved by the steel-concrete composite reinforcement technique andit can be widely used in bridge reinforcement.