Research On The Static Properties Of Cantilever Parameters Of Simply Supported Beam Arch Composite Bridge With Cantilever

With the development of modern transportation technology,various forms of composite Bridges have been conceived and completed.Simply beam arch composite bridge with cantilever has the following advantages:strong adaptability to the foundation,large span capacity,unique advantages in shape,facilitate the longitudinal combination of other bridges etc.It is of great significance to study this kind of the bridge.There are very few research achievements on this kind of bridge at home and abroad.Therefore,this paper takes the guitang river bridge as the background,In this paper,finite element method and analytical formula method are used to explore the influence of cantilever parameters on the internal forces of the key sections of the structure.And optimized the guitang river bridge.The details are as follows:(1)The mechanical properties of simply supported beam arch composite bridge with cantilever are fully understood,The mechanical simplification of the simply supported beam arch composite bridge with cantilever is carried out.Based on the force method,and the assumption of derrick membrane tension,The formulas for calculating the internal force and displacement of simply supported beam arch composite bridge with cantilever are derived.This paper provides a simple and practical calculation formula for the bridge.(2)A simplified finite element model of Midas Civil was established,The variation law of internal force of each key section with cantilever load under the action of dead weight is studied respectively for rigid arch of rigid beam,flexible arch of rigid beam and rigid arch of flexible beam.At the same time,the results of finite element and analytical solutions of the three systems are compared,and the accuracy of the analytical formula is verified.(3)On the basis of grasping the mechanical characteristics of simply supported beam arch composite bridge with cantilever,the cantilever parameters of guitang river bridge are optimized based on the analytical formula derived.The finite element model of guitang river bridge was established,and the results of internal forces and displacements of each key section of the structure before and after optimization were compared and analyzed under constant load,in the limit state of normal use and in the limit state of bearing capacity.