Research On Key Technology Of Construction Of T-rigid Frame Bridge With Trans-rail Railway

With the continuous increase of the total mileage of railway operations in China,the railway transportation network is increasingly densely intertwined.In order not to affect the normal operation of high-speed railways,the construction technology of bridge turning construction has emerged as the times require,and has achieved rapid development in recent years.In this paper,the paper carried out related research workers in the context of a cross-railway swivel bridge,including:(1)Introduced the method principle of bridge swivel construction and the applicable bridge type of different swivel methods.This paper summarizes the problems of partial deformation and stress analysis of ball joints in the construction of cross-rail bridges,the control of full-frame brackets,and the optimization of the unevenness of the rotating ball joints;(2)The Midas software was used to analyze the structural response of the box girder during the removal of the bracket;The basic principles and characteristics of the grey system theory and the prediction methods and steps of the metabolic GM(1,1)model are introduced.Through the prediction of the beam end deflection,it is proved that the GM(1,1)model based on the metabolism has certain feasibility for the beam end deflection prediction during the removal process of the T-shaped rigid frame bridge.The model can predict the deflection that meets the requirements of actual engineering precision;(3)The weighing test and the swivel control research of the T-type rigid frame bridge were carried out.The structure is subjected to the weighing test analysis by the ball joint rotation method,the unbalance moment and the eccentricity before the T-conversion body are tested,and the calculation ball is derived.The friction coefficient of the hinge and the weight of the counterweight ensure the smooth running of the T-construction body and provide reference for the construction of the same type of bridge swivel;(4)The finite element software Ansys is used to analyze the deformation and stress of the ball joint under the action of positive load and partial load.By analyzing the eccentricity of the T-type rigid frame bridge,the eccentricity is 5cm,10 cm,15cm,20 cm.It is found that with the effect of no eccentricity of the structure,under the action of eccentricity,the ball joint will undergo slight rotation,the force of the ball joint,The deformation is no longer symmetrical,showing a phenomenon in which one side increases and one side decreases,and this phenomenon becomes more pronounced as the eccentricity increases;(5)For the stress concentration phenomenon at the joint between the turntable and the upper ball joint,the stress value exceeds the design compressive strength of C55 concrete by 25.3 MPa,and the method of increasing the radius R of the column hinge is proposed to reduce the stress concentration phenomenon here.It has been found that an increase of 7.7% of the hinge radius can reduce the maximum stress of the turntable by 20.1%,and the radius of the hinge is appropriately increased,and the force of the turntable is significantly improved.