Investigation Into Influences Of Compressive Zone Expansion Force On Prestressed Concrete Beam’s Flexuralcapacity

Based on the existing experimental study of unbounded perstressed beam with compressive zone rebar corrosion, the article study the bearing capacity of bonded prestressed concrete beam with compressive zone rebar corrosion through the finite element method, and establishes bonded prestressed beam calculation formula of ultimate bearing capacity under the corrosive action.In this paper, the finite element software ABAQUS is used to simulate the existing unbounded perstressed beam with compressive zone rebar corrosion. Comparing the simulation results with the experimental results show that the finite element calculation results were consistent with the experimental results, the feasibility of finite element simulation method is well verified. On this basis, ABAQUS is used to establish27bonded prestressed concrete beam. Two kinds of states which the compressive zone reinforced with and without rust corrosion are simulated. Extracting the calculation results it can obtain the load deflection curve of the prestressed beam under the two states with compressive zone reinforced with and without rust corrosion. The results show that the flexural bearing capacity of prestressed beam will be reduced after the steel corrosion in the compressive zone. On this basis, making further research on the effect that corrosion rate, protective layer thickness, effective prestressing this three factors have on the bearing capacity of prestressed beam. The research results show that with the increase of corrosion rate, the negative impact on the bearing capacity of pretressed concrete beam which caused by the steel corrosion in the compressive zone is increased. In the corrosion rate of the same circumstances, the ultimate bearing capacity of prestressed concrete beam down different levels with different protective layer thickness, the greater the ultimate bearing capacity decline in greater degree. When compressive zone rebar corrosion rate is the same situation, effective prestressing steel corrosion will affect the damage degree of prestressed beam’s cross section stiffness with compressive zone rebar corrosion.The formula of ultimate flexural bearing capacity was deduced under compressive zone steel rust expansion. Contrast the formula derived from the finite element calculation results and the calculation results, the calculation results are in great agreement. The applicability of the formula established in this paper is verified. Providing basic basis for the assessment of bonded prestresed concrete beam strength degradation under the action of compressed reinforced corrosive force.