Research On Mechanical Performance And Device Of Joints Of Fabricated Hollow Slab Bridge

With the rapid development of the social economy,the construction of highway traffic is advancing by leaps and bounds,and the bridge as the connecting hub of highway traffic can develop rapidly.At present,there are more than 700000 medium and small span bridges in China.In the medium and small span bridges,the fabricated hollow slab girder bridge is widely used because of its simple structure and convenient construction,but a large number of diseases also appear.Hinge joint disease is the main disease of this type of bridge.Hinge joint plays the role of transferring transverse load in a prefabricated beam bridge.Once the hinge joint disease occurs,it will cause uneven stress on each beam and slab,and eventually lead to the serious consequences of single plate stress,which has a huge threat to the safety of the bridge.Therefore,in view of the current emergency situation,it is necessary to conduct in-depth research and Analysis on the hinge joint of the traditional fabricated hollow slab girder bridge at this stage,and on this basis,improve the hinge joint device to reduce the hinge joint disease.According to the current situation of hinge joint disease,this paper studies the hinge joint from three aspects: field investigation,finite element simulation analysis and model test.(1)Through theoretical and experimental research,an improved hinged joint device of prefabricated beam bridge is proposed,which can effectively improve the bearing capacity and durability of the hinge joint.(2)The experimental results show that the failure process of the traditional hinge joint device model is a brittle shear failure,and the embedded reinforcement under the hinge joint is sheared and stripped when the failure occurs.The failure process of the improved hinge joint device model is a plastic tensile failure,and the overall mechanical performance is good.When the concrete at the hinge joint is damaged,the steel plate and reinforcement can continue to transfer the lateral load.Compared with the traditional hinge joint,the bearing capacity of the improved hinge joint is increased by42% and the anti deflection deformation is increased by 30%.(3)The finite element software ABAQUS is used to simulate and analyze the influence of different load positions,vehicle load,elastic modulus and pavement thickness on hinge joint.It is determined that the most unfavorable position in the transverse direction of 1 / 2 bridge span;under the overload of vehicles,the bottom of hinge joint bears huge tensile stress;with the increase of the elastic modulus of hinge joint,the overall stiffness of the bridge is increased,and the longitudinal normal stress of the hinge joint is the greatest influence;according to the stress analysis,it is the most reasonable to set the pavement layer of 10 cm,too thin can not make the hinge joint and plate beam better overall stress,too thick is not It’s not easy.This study has important reference value for improving the hinge joint disease of prefabricated hollow slab girder bridge.