The Research And Application Of The Hollow Slab Bridge Reinforcement Method

Medium-Small span simply hollow board bridges with convenient for constructing andfinding material, high durability, and beautifully appearance and many other advantages，makes the widespread adoption of our country. Recently,with the violent increase of thetraffic flow, and there are more overweight vehicle on the bridge which had been runningfor years,now it is time to repair and reinforcement. This issue carried out load-improvingprototype test for the insufficient stiffness on the basis of the theoretical analysis. Researchthe property and reinforcement effect of the hollow slab beam which was strengthened byexternal pretesting and bridge deck pavement embedded by steel bars.The static test carried out five slices of simply hollow slab beams16meters long, L1beam wipe off as comparison beam, L2beam reserved original bridge deck pavement, L3beam was reinforced only by deck pavement embedded, L4beam was strengthened byexternal pretesting and deck pavement embedded, and L5beam was strengthened byexternal pretesting and carbon fiber composite. Then the bending performance of beamswas studied for researching the characteristic of the five type of beams. The different affectto the beams was compared, and contrast the result of experiment with the result offormulary.The experimental research showed: due to the bridge deck pavement have the effect toincrease the sectional area and stiffness of the beam, it is necessary to consider it as part ofthe structure, The beam bending stiffness increased20.2%compare with the comparisonone under the highwayⅠload; Embedded steel bars in the bridge deck pavement canenhance the connection of new-old concreted and increase the sectional bending stiffness8.5%. External per-stressed technique had good control on the crack of the concretebeam, and the reinforced beam’s deflection and stress lower than non-reinforced concretebeam under the same load, and increase the sectional bending stiffness9%under thehighwayⅠload. And tension can make the crack closure of externally prestressed tendons,reduce the cracking of cracks, pasting carbon fiber can control the increase of crack width,reduce crack spacing and crack is more even, better matching and the force of prestressedof externally prestressed tendons.