Research on the Multiple-Track Coefficinet for the Fitigue Calculation of Railway Steel Bridges
|School||Southwest Jiaotong University|
|Course||Bridge and Tunnel Engineering|
|Keywords||Railway Steel Bridge Fatigue Damage accumulation Multi-line coefficient Multi-line impact factor Range Method Monte Carlo method|
With the development of transport , a growing number of four - and six-lane railway bridges have been built, multi-line train at the same time the role of the impact of structural fatigue damage on the bridge has become an urgent research topic . In this paper, on the basis of existing research results , using the range method and Monte Carlo method , multi-line railway steel bridge fatigue strength check calculation coefficient and describes their advantages and disadvantages and scope of application of the two methods . First , certain assumptions based on the range method to establish the mathematical model train bridge encounter , solve the encounter probability and frequency of train on the bridge , combined with Miner linear cumulative damage theory derived operators of Q train bridge damage caused , according to the definition of multi-line coefficient derive the formula for calculating the coefficient of railway bridges two-wire, three-wire , four-wire . To facilitate the practical engineering applications , multi-line coefficient summarized as a formula and calculate the forms . Known by the poor law analysis , the factors that affect the coefficient of the multi-line there are two categories : the first category of factors associated with the bridge , including the bridge span bridge in which the location of two parameters ; second category of factors and train the way they operate , including the type of train , speed, departure time interval parameters . By collecting data , using the Monte Carlo method to simulate the two-wire and four-wire train operators , and more than a few parameters of the multi-line coefficient . By analyzing the simulation results of the four - line railway , with the meet to correct multi-line train run on multi-line bridge fatigue damage coefficient k ' . Than the multi-line coefficient k. More regularity and stability , we propose to use four-wire the influence coefficient k'n instead of four - line coefficient kn multi-line train at the same time to consider the role of bridge structural fatigue damage . Finally, using the ANSYS , and MIDAS finite element software to establish two-wire and four-wire steel truss cable-stayed bridge model , compare lane coefficient calculated using the range method and norms simplify calculated the difference between the two - coefficient ; concurrently using the Monte Carlo method to calculate the the railway bridge four-wire the coefficient k4 and four-wire influence coefficient k'4 steps .