Study On The Stiffness Of GFRP-concrete Composite Bridge With Interfacial Enhancement

GFRP-concrete composite bridge deck is a new form of bridge deck?The bridge deck,combine GFRP with concrete by some connection Combine GFRP with concrete by some kind of connection,take full advantage of GFRP good tensile properties and concrete good compression performance,improve bending stiffness and reduce the stress deformation.The bridge deck has the advantages of light weight,high strength,corrosion resistance,light weight and so on.Due to the combination of GFRP and concrete bridge deck of related research is not yet mature,GFRP deck and concrete interface connection problem still haven't been solved well,material performance underutilized.For this reason,the paper designed two kinds of interface connection methods,including wet bonding method and sand bonding method,to strengthen the interface connection.The load bearing capacity and stiffness of the composite bridge deck with the method are improved,making the performance of the two materials advantages into full play.The main work of this paper is as follows:(1)This paper designed 10 pieces of GFRP-concrete composite plate with different interface connection method,concrete thickness and concrete strength grade.Under the condition of static test,the experimental phenomena and data are observed and recorded,and the strain-deflection curve and the critical strain curve of the composite bridge deck specimen are obtained.(2)In this paper,the failure phenomenon of the specimen is analyzed,and the variation law of the mid-span deflection and stiffness of the specimen under different load,specimen interface connection method,concrete thickness and concrete strength grade are obtained.According to the variation of the strain in the middle section of the specimen along the section height,it is found that the mid-span section of the specimen meets the assumption of plane section.(3)The existing stiffness calculation method is collated and analyzed,and the bending stiffness calculation model of the interface reinforced GFRP-concrete composite bridge deck is established,which is based on the deflection and strain variation of the specimen.The validity of the model is validated by the test data.(4)The ABSQUS finite element analysis model of GFRP-concrete composite bridge deck is established.The deflection and strain variation of composite bridge deck are studied,and the results are compared with the experimental data,obtained the consistent results.