Study On Damage Causes Of Diaphragm Of T-Beam Bridge On Heavy Haul Railway And Its Influence On Static And Dynamic Performance

Diaphragm damage is one of the common diseases of heavy-haul railway bridges.It tends to weaken the lateral connection performance of bridges,reduce the torsional stability,seriously endanger the safety and durability of bridges,and adversely affect the vehicles on the bridges.influences.In this paper,the factors affecting the cracking of the diaphragm are calculated and analyzed to reveal the cause of the cracking.At the same time,the health status of the bridge after the diaphragm damage and the driving safety are calculated from the perspective of dynamic performance,and the impact on the vehicle and the bridge is evaluated.And corresponding optimization is proposed and reinforcement measures to calculate the dynamic and static effects on the bridge after reinforcement.The main work and conclusions of this paper are as follows.(1)There are many reasons for the damage of the diaphragm.In this paper,the main factors causing the damage are summarized by analyzing the common diseases of the bridge,which are the eccentricity of the bridge and the void of the support,and the actual parameters of the bridge relying on the Ziya New River Bridge.The calculation of the transverse diaphragm stress is carried out by different limits of the eccentricity of the bridge and the void of the support.The influence of the eccentricity of the bridge and the void of the support on the force of the transverse diaphragm is analyzed.(2)The vehicle-bridge coupling dynamics theory is used to establish the equation of motion balance between vehicles and bridges.The coupled axle system is established by the coordination of displacement and force.The newmark-? method is used to solve the amplitude of train and bridge in all directions when the train crosses the bridge.And acceleration,using these dynamic parameters to evaluate the safety performance changes of the two diaphragms after the damage occurred.The influence of the diaphragm damage on the joint performance of the two main beams of the double T beam is analyzed.(3)Damage to the diaphragm will lead to the development of the overall damage of the bridge.Therefore,the damaged diaphragms need to be repaired in time,including durability repair and structural repair.In this paper,two diaphragm reinforcement schemes are proposed,and the variation of the diaphragm and the dynamic parameters of the bridge before and after reinforcement are calculated.The change situation,analyze the static and dynamic effects of the diaphragm reinforcement on the bridge,compare the optimization scheme with the construction economy and workload,and evaluate the reinforcement effect.