Study On Flexural Behavior Of Bonded Partially Prestressed Concrete Beams With 600MPa Reinforced Bars

600MPa steel has advantages of high strength,saving energy,reducing material consumption,and good ductility.Currently high-strength steel has been widely used abroad in the major industrialized countries.However,the research on the 600 MPa steel is still blank,and the trial data of reinforced concrete members is lack in China.For the promotion and using of this new type of steel,and the promotion of our construction steel with international standards,it is necessary to conduct in-depth research on its performance and form a complete technical data,which provides technical basis for the development and application of 600 MPa grade steel.The flexural behavior of 5 bonded partials prestresed concrete beams with reinforced bars of 600 MPa was studied under static load,with the main parameters of concrete strength and non-prestressed reinforcement ratio.Prestressed reinforced load—stress relationship,nonprestressed reinforced and concrete load—strain of test beams were researched.Based on the experimental data,the crack resistance,flexural bearing capacity,crack width,deflection and ductility of the test beams are researched.The yield strength of non-prestressed reinforced bars in prestressed concrete beam with design value of 600 MPa can takes 500 MPa.It provides reference for the application of 600 MPa in the prestressed concrete structure.The results shows that,with the increase of 600 MPa non prestressed reinforcement ratio,the crack resistance of the members is not significantly changed,but the flexural bearing capacity of the members is improved.Concrete strength has no significant effect on the crack resistance and bending capacity of the members,while the ductility of the member is improved obviously.The formulas of crack resistance,flexural capacity,prestressing loss,deflection and ductility given by "Code for Design of Highway reinforced Concrete and Prestressed Concrete Bridges and Culverts" JTG D62-2004 are still applicable for bonded partials prestresed concrete beams with 600 MPa reinforced bars.The finite element model bonded partials prestresed concrete beams with 600 MPa reinforced bars is established by ABAQUS software.Date comparsion between software and test show that simulation result of static analysis have good agreement with the test results.