Analysis On Distortional Effect Of Composite Box Girder With Corrugated Steel Webs

The corrugated steel web composite box girder is a new type of structure following the prestressed concrete box girder.It originated in France and was popularized in Japan and other countries subsequently.Compared with the concrete box girder,the structure can effectively improve the prestressing efficiency,reduce the self-weight of the beam body,speed up the construction progress,and avoid the problem of cracking of the concrete web,so the application range of corrugated steel web composite box girder is more wide.Through theoretical analysis and finite element numerical simulation,the distorting effect of corrugated steel web composite box girder is studied systematically.The main research contents of this paper include the following aspects:(1)Applying the energy variation calculus based on the principle of stationary potential energy,the differential equation of distortion control of corrugated steel web composite trapezoidal box girder is derived and the initial parameter solutions to the equation were achieved.The distortion internal forces and distortion displacements expression of the composite box girder are derived under concentrated load and distributed load.The distortion warping stress of corrugated steel web composite box girder and traditional concrete box girder is compared by numerical examples,the results show that the corrugated steel web composite box girder is 1.69 times as much as the concrete box girder in the maximum distortion warping stress.(2)Using the plate beam frame method to derive the distorted control differential equation of corrugated steel web combined rectangular box girder,the distortion internal force and distortion displacement are solved by the elastic foundation beam comparison method.The distortion warping stress of corrugated steel web composite box girder and traditional concrete box girder is compared by numerical examples,the results show that the corrugated steel web composite box girder is 1.50 times as much as the concrete box girder in the maximum distortion warping stress.(3)Using the spatial finite element analysis method to analyze and verify the accuracy of the two calculation theories,the distortion differential equations of the composite box girder using the elastic foundation beam method are obtained with high precision and the corrugated steel web composite box girder is confirmed.The basic assumption used in the distortion analysis is to satisfy the characteristics of its force.(4)The finite element ansys was used to study the influence of high-span ratio,corrugated steel web shapes,corrugated steel web thickness and the number of diaphragms on the distortion effect of corrugated steel web composite box girder subjected to eccentric load.The results show: Under the premise of not increasing the self-weight,increasing the number of transverse diaphragms can effectively improve the longitudinal warping stress of corrugated steel web composite box girder under the eccentric load;When the other factors remain unchanged,the longitudinal warping stress increase coefficient of the corrugated steel web composite box girder decreases with the increase of the shape parameters b,α of the corrugated steel web;With the thickness of the corrugated steel web decreases first and then increases,it increases with the increase of the high span ratio.According to the analysis results,measures that can effectively reduce the longitudinal warping stress of the composite box girder were raised.