The Mechanical Behavior Of Steel Bridge Deck Pavement Structure Pasting By GFRP Sheet

Thickness of steel box girder roof of the early-built long-span orthotropic steel bridge inour country is generally thin that would result in these damage types like crack, elapse andupheaval on the steel bridge deck pavement not long after opening traffic. One of the keytechnologies in long-span bridge construction is steel box girder bridge deck pavement; itscore is to increase the stiffness of the pavement without increasing its deadweight load.This study features on the reason why steel box bridge deck pavement would break,proposing that pasting certain thickness GFRP plate (glass fiber reinforced plastics) on thesteel bridge panel with intention of not to increase their deadweight load in the reference withrelevant achievements, and study the mechanical behavior of this new type steel bridge deckcomposite pavement structure.The mechanical characteristics of composite pavement layer pasted with GFRP wereanalyzed by FEM software in order to compare the strain and stress in steel bridge deckpavement pasted on GFRP with different modulus. Adopting the method of interlaminar sheartest which had been patented to test interlaminar shear performance of symmetry cuboidsspecimen pasted with GFRP and analyzed the influences of different factors on theinterlaminar shear performance. The composite beam fatigue test was used to test theinfluence of pasting GFRP on fatigue performance of the pavement structure. The fatiguedamage process of the composite beam pasted with GFRP was also predicted on the basis ofdamage mechanics theory.Stress, strain and the vertical deformation in the pavement structure all changed indifferent degrees when pasting different modulus GFRP. Bonding performance betweenGFRP sheet and asphalt concrete would reach the best when GFRP contact surface roughdegree was that sanding particle size is2.36~4.75mm for single side, bonding material was0.4kg/m2modified asphalt, positive pressure was0.7Mpa and the temperature was5℃.Compared with beams not pasted with GFRP, fatigue life of the beams pasted with GFRPextended the7.81times.It will form a kind of durable structure of steel bridge deck pavement through above study. At the same time, it creates a new train of thought in solving that thickness of largespan steel bridge deck is too thin.