Analysis Of Force Principle About Curved Twin-box Steel Girder Bridges

With the oversupply of steel production capacity in China and the guidance of the State,in recent years,curved steel box girder bridges have been used more and more in urban bridges and highway bridges,especially to adapt the surrounding topography,features,and spans.When some lines have higher requirements for line types,in the future it will develop very well.Previous single-chamber steel box girder bridge study is mostly.Based on a two-span single-curve curved steel box girder bridge with a radius of 92 meters,the mechanical mechanism of this type of bridge will be studied.Research related content is as follows:First of all,I use the Midas/civil of a software to establish the single beam model and the beam lattice model,and use Ansys of a software to establish the shell and shell element model.The overall calculation results meet the specification requirements.The three groups of models have their own weight phase,overall temperature increase,overall cooling,temperature gradient,and movement.We will know the similarities and differences of the load and other conditions under the same load conditions.As far as the advantages and disadvantages of the model are concerned,the Midas/civil single beam model and the beam lattice model take less time and can reflect the overall response of the structure,but local analysis is lacking.The stress distribution of the Ansys plate and shell element model is more accurate,which can better observe the local stress of the structure.However,there are many unit nodes and the calculation takes a long time,which is suitable for local analysis.Secondly,through the rigid beam method and the modified rigid beam method,combined with the eccentricity generated by the curved bridge in this paper relative to the straight bridge,the theoretical calculation method of the lateral internal force distribution coefficient of the Twin-box single-curve curved steel box girder bridge is explored,and through the data extracted from the Midas /civil beam model and the Ansys plate and shell element model are compared and verified.It is concluded that the lateral internal force distribution coefficient calculated by the theoretical calculation method and the lateral force distribution coefficient obtained by the model extraction value are within 5%,so The theoretical calculation method is applicable to the calculation of the internal force distribution coefficient of a Twin box single-room curved steel box girder bridge with a radius of 92 meters.Then,using the 40-m minimum boundary defined by the specification as a zero boundary point,establish a different radius to explore the applicable range of the theoretical calculation method,and the result is that it is suitable for approx 68 meters.Finally,through the establishment of single box single-room curved steel box girder bridges with different radii and two-box single-room curved steel box girder bridges,the influence of the curvature radius on its distortion normal stress under self-weight load and eccentric load line load is explored.Under the effect of self-weight,the overall situation will increase as the radius decreases and the normal stress value increases and the magnitude of increase will increase.Under eccentric loads,the normal stress value of the quarter-section distortion increases with decreasing radius.However,the distortion normal stress values of half-section and three-quarter section decrease as the radius decreases.The smaller the radius is,the faster the distortion normal stress changes.In this paper,the conclusions of the analysis and calculation of the Twin-box single curved steel box girder bridge are obtained.These conclusions have certain guiding significance and reference value for the same type of steel box girder bridge.