Long-span UHPC Bridge's Dynamic Performance Evaluation Based On The Analysis Of Coupling Vibration

UHPC is a new material with excellent properties such as high toughness,high compressive strength and good durability.The emergence of UHPC material enables bridge structures to achieve longer span,smaller component size,more convenient construction,shorter construction period,less adverse impact on the environment,and its excellent durability can significantly reduce the cost of later maintenance and effectively extend bridge`s service life.UHPC materials will be widely used in bridge engineering.Bridge dynamic performance evaluation is an important index to evaluate bridge performance.However,the current research on UHPC Bridges mainly focuses on static performance,and there are few studies on dynamic response analysis of vehicle-bridge coupling vibration of UHPC Bridges.Therefore,it is of great significance to evaluate the dynamic performance of UHPC Bridges.The main research contents of this paper are as follows:(1)On the basis of vibration theoretical analysis,the vibration equation of two-axle one-half vehicle model is deduced.Based on the whole process of iteration method,through the axle force coupling relationship,using Matlab to solve the vehicle vibration equation,using the transient dynamic analysis module of ANSYS to solve bridge vibration response,through two procedures of data interaction iteration,axle coupling vibration response analysis of calculation program is compiled,and combined with literature,verify the reliability of the program.(2)Summarized the calculation methods of impact coefficient in the regulations of various countries,the advantages and disadvantages of base frequency and bridge span are analyzed.and introduced and analyzed the commonly used evaluation methods and standards of riding comfort,and according to the relevant methods to compile the corresponding riding comfort analysis program.(3)Aiming at UHPC simply-supported beam bridge(43.75 m U-type UHPC simply supported beam bridge and 102 mUHPC simply supported box girder bridge)and 400 m long-span UHPC continuous beam bridge,the self-compiled vehicle-bridge coupling vibration analysis program is used to analyze the impact coefficient,spectrum characteristics and driving comfort of the two major influencing factors of speed and road roughness.