Dynamic Characteristics Research Of Vehicle And Comb-type Expansion Joint

Bridge expansion joints are essential parts of the bridge structure,which connect two bridge decks and stabilize the bridge structures.The bridge expansion joints are directly rolled by the vehicles and are exposed to the air environment for a long time.Slight deficiency in the design and construction of the expansion joints will cause the damage of the expansion joints system.As a result,the driving state of the vehicle will be changed.Whats more,the comfort and safety of driving will drop directly,the driving life of the vehicle will be affected as well.The destruction of the expansion joints will lead to a significant increase in the impact of the vehicle on the bridge structure.The destruction speed of the deck pavement will be accelerated significantly,even the safety of the main structure of the bridge will be affected.The combtype expansion joint is choosed for this research.The main contents are as follows:(1)The modeling method of tires in ABAQUS is studied.And the structure of tire and comb-type expansion joints are reasonably simplified.The material modeling problem of rubber-cord composite structure is defined.Then the inite element model of 12R22.5 radial tire of track and the comb-type expansion joints are obtained;(2)The accuracy of the finite element model of the tire is verified by comparison of simulation and experimental data.Inflation analysis,stiffness analysis and rolling analysis are conducted on the tire to study the mechanical properties.Then the force distribution of the belt is studied when the tire is grounded.The tire structures are simplified to facilitate modeling and analysis.(3)The static characteristics of the comb-toothed expansion joints such as the amount of expansion and contraction,load,and working conditions are analyzed.The tire boundary conditions are defined and the process of the tire rolling over the comb type expansion joint is simulated.The stress curves of the expansion joint under different joint widths and different vehicle speeds are obtained.The stress of the concrete under the installation of the expansion joint was investigated.The applicable scope of the simplified structure of the tire was determined.(4)The model parameters and mechanical parameters of a certain truck are determined.The models of the truck and the comb-type expansion joint are established using Recurdyn software.The differences between the rigid wheel model and the finite element flexible wheel model are compared and analyzed.(5)When the vehicle passes through the expansion joint at high speed,the vibration of the vehicle body is rather small while the impact on the structure of the vehicle is greater.the greater the joint width,the greater the vibration of the vehicle through the expansion joint.When the expansion joint is lower than the horizontal road surface,the vibration of vehicle is smaller and make people more comfortable.