The Performance Of The Lateral Load Distribution Of Multi Beam Rigid Connection With Continuous Box Girder Bridge

The practical space theory analysis of highway girder bridge is the calculation method of the load transverse distribution influence line of beam bridge.The basic assumption is to use the approximate internal force influence surface instead of the internal force influence surface to calculate in the range of error allowable.The bridge is a structure of space stress.Through reasonable transformation to plane problem,the basic idea is to replace the influence surface of the internal force by using the approximate internal force influence surface which is combined with the influence line of the load transverse distribution combined with the single beam longitudinal internal force influence line.In the calculation of lateral load distribution,it is strictly stated that only a half wave sinusoidal load on a simple beam bridge with equal cross section only exists in the lateral distribution of load.In this paper,the relationship between influence line and influence surface is briefly introduced,and the property of transverse load distribution is explained.The calculation principle and formula of the influence line of common load lateral distribution of simply supported beam bridge are summarized.Through the summary of the lateral distribution of the load of the simple supported beam bridge,the method of calculating the transverse distribution of the load used in the continuous beam bridge is introduced.In order to analysis the accuracy of the transverse load distribution,using grillage method comparative analysis of simulation bridge superstructure,namely the basic principles and the principle of lead beam slab structure,beam slab structure and box girder grillage division and girder section geometric properties calculation method and formula.The effect of grillage model to calculate the control section of the internal force,longitudinal force influence line and single beam model in longitudinal comparison,the transverse and transverse load distribution influence line compared to the control of girder section in the longitudinal internal force influence longitudinal single beam model and the strict line is similar to that of other similar in the longitudinal girder on.The degree of similarity between the lateral and lateral distribution of the internal force is different because of the different control sections.The similarity degree of the influence surface of the bending moment is higher than that of the shear influence surface.Therefore,the error of the moment value calculated by the lateral load distribution coefficient is smaller,and the error of the shear value is larger.Due to the general specification of highway bridge and culvert design,there is no explicit provision for the calculation of transverse load distribution coefficient.Designers can choose different load lateral distribution coefficient calculation methods according to actual conditions.For different calculation methods of lateral distribution coefficient of load,the basic assumptions used in the calculation are different,and the calculation results aredifferent.In this paper,a 4 * 40 m prefabricated concrete continuous girder bridge is used in Xianhe bridge.The skew is the transverse load distribution coefficient and the modified rigid cross beam method is adopted.The internal force through the rigid crossbeam method modified calculation of internal force calculation of grillage method and value were compared and analyzed to calculate the bending moment of rigid crossbeam method modified values in the cross section of minimum relative error,the relative error of the control section of the other different.The relative error of the bending moment value of each control section is not more than 15%.The relative error of the shear value calculated by the modified rigid beam method is larger,and the relative error of each control section is different,and the maximum error is over 60%.According to the modified rigid transverse method,the corresponding correction coefficients for each control section are given.The maximum correction coefficient of the bending moment of the side beam is not more than 1.2,the maximum correction coefficient of the bending moment of the middle beam is not more than 1.1,and the correction coefficients of the shear values of the control sections are different.