Study On Calculation Method And Parameter Influence Of Transverse Distribution Of In-service Assembly Beam Bridge

The existing classical theory of transverse distribution of bridges is more accurate for analyzing the calculation results of new bridges.However,for old bridges with certain service life in service,the damage caused by environmental erosion and the fatigue load of heavy traffic.The influence of the existing bridge structural performance can not be neglected.These influences include the deterioration of the rigidity of the beam body,the damage of the transverse connection structure and the change of the structural force under long-term load and heavy load.Considering the influence of these factors on the lateral distribution of the existing bridge,the modification of the existing classical transverse distribution theory can be used to evaluate the structure performance of the existing fabricated bridge more accurately,which has certain theoretical significance and engineering practical significance,Engineering internal force analysis accuracy.In addition to these structural parameters of the details of the changes,from a large direction,the more obvious structural changes in the bridge structure of the horizontal distribution of load changes also have an impact,including span,span ratio,the number of beams,paving and guardrail Studying the influence of these parameters on the lateral distribution of bridges can provide reference for further improvement of theory and expand the applicability of transverse distribution theory for further research.First of all,the article chooses the traditional rigid beam method which is suitable for narrow bridges.Based on this,considering the degradation of the rigidity of the main beam,it is considered that the additional deflection caused by the deflection without loss and the stiffness before loss,Deduced the rigid beam method and calculated the vertical axis value of each beam influence line,which is more accurate than the traditional theoretical calculation results.Secondly,on the basis of the beam-on method,considering the influence of the stiffness of the wet joint and the deformation of the box girder corner on the parameters of the traditional method,the parameters of the coefficient matrix are redefined to correct the theory.At the same time,The Ansys finite element solid model is established to verify the theoretical calculation results.Finally,several main structural parameters of the prefabricated beam bridge are selected,including the span,the number of beams,the number of beams and the pavement thickness.Three sets of data are taken for each parameter,and 12 Midas civil finite element models are established,the influence of each parameter on the horizontal distribution is studied to provide reference for the improvement of the above research theory,which provides reference value for further study of the stress distribution of the bridge in service.The results show that for the existing fabricated beam bridge,the revised theoretical calculation method considering the stiffness of the main beam,the lateral joint stiffness and the distortion effect of the small box beam structure is closer to the actual condition of the bridge,which is closer to the finite element result;As for the bridge,with the variation of structural parameters such as bridge span,span ratio,diaphragm and pavement thickness,the horizontal distribution shows a certain regularity.Combining the two aspects of research and analysis,not only broaden the scope of application of the theory,but also provide engineering reference value for correctly evaluating the existing fabricated beam bridge.