Research On The Anti-Bending Performance Of Bolt-Based GFRP-Concrete Composite Beams

In recent years,FRP materials have been characterized by high light and high strength,high strength,large modulus and high corrosion resistance,and in the field of civil engineering,FRP materials and combination structures have become an important development direction.GFRP-concrete composite beam as one of the main components of bridge,the connection between the upper concrete and the upper wing edge of the GFRP profile is particularly critical,and the GFRP profile and concrete will be sliding due to the disharmony of material deformation,which in turn will have an impact on the anti-bending performance of the composite beam.In this paper,bolts are selected as the connection method at the interface of the composite beams,and the bending performance of the GFRP-concrete combination beams based on bolt connections is explored by a simulation and experiment of ABAQUS finite element.The main studies completed are as follows:(1)The bolt diameter,bolt spacing and concrete strength are the three main factors,and 12 GFRP-concrete combination beams are designed,and the cross-middle deflection and beam end slip of the 12 combination beams are calculated and analyzed by ABAQUS finite element software,and the results show that the bolt diameter has no significant effect on the bending performance of the combined beam,and the bolt spacing and concrete strength have a significant effect on the anti-bend performance of the combined beam.The load-deflection curve and load-slip curve of the combined beam are significantly linear.(2)On the basis of ABAQUS finite element simulation,3 GFRP-concrete composite beams were selected for bolt spacing for beam test,the test results showed that the combined beam struck with the height change of the cross-strain conforms to the flat cross-section assumption,the load-deflection curve,load-slip curve obtained by the test and the ABAQUS finite element simulation obtained by the same trend curve,and the finite element simulation of the cross-flexion,beam end sliding.(3)This paper analyzes the force of the GFRP-concrete composite beam,and concludes that the cross-medium deflection of the combined beam consists of the deflection caused by bending deformation and the deflection of the interface,and deduces the value of the corresponding slip deformation coefficient,comparing thetheoretical calculation results with the experimental value,the maximum difference is9.1%.Due to the generation of interface slip,the anti-bending carrying capacity of the combined beam will also be reduced,the anti-bending carrying capacity reduction coefficient is introduced,and the formula of the anti-bending load reductioncoefficient is obtained.