Research On Hinge Joints And Reinforcement Technology Of Wide-variable Cross-section Prestressed Hollow Slab Bridge

The force transfer of prestressed wide hollow slab bridge with tapered section mainly relied on the hinge joints.Due to the structural defects of shallow hinge joints and the increasing traffic flow and vehicle load,the transverse force transfer performance deteriorate severely,which is prone to cause single beam bearing phenomenon of bridge,thus threats the structural safety.Therefore,the reinforcement of the transverse connection of in service prestressed wide hollow slab bridge with tapered section becomes an urgent issue for the bridge industry,especially to eliminate potential safety hazard of single beam bearing and prolong the service life of hollow slab bridge.This thesis researches several different methods to reinforce the transverse connection of wide hollow slab bridge,the results is of reference value for the prestressed wide hollow slab bridge with tapered section.This study first analyses the damage mechanism of the transvers e connection of prestressed wide hollow slab bridge,and summarized several frequently used prevention measures for construction and design,and proposed some different reinforcement methods based on the mechanism for prestressed wide hollow slab bridge.T his study is based on a reinforcement project of prestressed wide hollow slab bridge.Finite element analysis was implemented to simulate the joint hinge reinforcement.Load test was conducted to compare the slab's transverse and longitudinal stiffness under different reinforcement design,and the measured value is compared with the simulated theoretical value to analyze the pros and cons of different reinforcement design.The coefficient of collaborative performance is proposed to evaluate the hinge joint force transfer capacity after reinforcement.The research conclusions are as follow:1.The prestressed wide hollow slab bridge mainly used shallow hinge joint,thus the structure has intrinsic defects.It is recommended that future design increase the size of hinge joint,especially the depth dimension,to ensure adequate shear capacity of joint hinge.2.With finite element simulation and load test,it was discovered that under same vehicle load,the method of "remove damaged beam and add ribs" has the highest transverse stiffness,next is the method of transverse prestress reinforcement,the method of steel cross beam reinforcement provides the least transverse stiffness.3.The method of steel cross beam reinforcement has better integrity than transverse prestress reinforcement,and the coefficient of collaborative performance improves significantly.