Nonlinear Finite Element Analysis Of Flexural Behavior Of Reactive Powder Concrete Beams Reinforced With Steel Bars And GFRP Bars

As one of the most commonly used structural materials in the construction industry and civil engineering field,reinforced concrete has many advantages.But in the course of its use,there will also be many practical problems,such as the durability of concrete structure is reduced due to the corrosion of steel bars and concrete carbonization,and the weight of the structure is heavier.Fiber reinforced plastics(FRP)bars have the advantages of corrosion resistance and high tensile strength.Reactive powder concrete(RPC)has the advantages of high strength,light weight and high durability.At present,concrete structures with FRP bars and reinforced bars and high-strength concrete structures similar to reactive powder concrete are being extensively studied by scholars at home and abroad,and have good prospects for development.In this paper,ABAQUS finite element numerical simulation is carried out on the experimental beams of reinforced active powder concrete and GFRP reinforced active powder concrete in the literature,The whole process of the test beam is analyzed,and the load midspan deflection curve simulated by the finite element method is compared with the test results to verify the accuracy of the finite element numerical model.On this basis,this paper designs the finite element analysis scheme of the reinforced and GFRP reinforced reactive powder concrete beams.Through the finite element software ABAQUS,the finite element numerical model of the reinforced and GFRP reinforced reactive powder concrete beams is established,and the non-linear analysis of bending performance is carried out.The load mid span deflection curve,failure mode and crack distribution of the simulated beams are investigated The whole process of simulated beam loading is studied,The load mid span deflection curve obtained from the numerical model is analyzed from three aspects.In addition,with the help of mathematical software,based on the strip method and the conjugate beam method,the calculation program of RPC beam with reinforcement and GFRP reinforcement is compiled,and the load midspan deflection curve of the simulated beam is obtained,which is compared with the results of ABAQUS finite element simulation,so as to further verify the rationality of ABAQUS finite element numerical model.Based on the results of nonlinear finite element analysis,the conclusions of scholars and the calculation theory of ordinary reinforced concrete,the calculation formulas of cracking moment and flexural capacity of normal section of RPC beams with reinforcement and GFRP reinforcement are derived.The results show that:(1)based on the finite element software ABAQUS,the numerical model of the test beam is established.Through the nonlinear analysis of the bending performance of the test beam,it is found that the finite element simulation results of the load midspan deflection curve are in good agreement with the test results,which verifies the accuracy of the finite element numerical model.(2)The results of ABAQUS finite element simulation are in good agreement with the load mid span deflection curve obtained by mathematical software program.The rationality of ABAQUS numerical model is further verified by mathematical software program.The load midspan deflection curve of the finite element numerical model is analyzed from three aspects,and the following conclusions are drawn:when other conditions are unchanged,if GFRP reinforcement is increased,the yield load of the hybrid reinforced beam will increase,the ultimate bearing capacity will increase,and the cracking load will remain unchanged;when other conditions are unchanged,if the reinforcement is reduced,the yield load of the hybrid reinforced beam will decrease,and the ultimate bearing capacity will remain unchanged It also decreases,and the more the reinforcement is reduced,the more the yield load and ultimate load are reduced,and the cracking load is basically the same;when the total force of reinforcement is basically the same,and other conditions are unchanged,the larger the reinforcement is,the greater the yield load of the hybrid reinforced beam is,and the cracking load is basically the same.(3)The calculated results of flexural capacity and cracking moment of the positive section of RPC beams reinforced with GFRP and steel bars are in good agreement with the results of ABAQUS finite element simulation,which shows that the established formula can be used for calculation and analysis.