The Research On Reasonable Design States And Parameter Of Extradosed Cable-stayed Bridge

With the continuous development of bridge technology in recent decades,as well as the emergence of new materials,new processes and new technologies,scholars are constantly breaking through the shackles of traditional bridge type,and creating many new ones.Among them,the Extradosed Cable-stayed Bridge is one of them.The shape of the Extradosed Cable-stayed Bridge is similar to that cable-stayed bridge,the force characteristic is similar to that beam bridge,it is a new type of bridge between these two types of bridges.The structure of the Extradosed Cable-stayed Bridge is more and more widely used,so it is very necessary to carry out the research on the bridge type.In the design work,after determining the main component parameters of the Extradosed Cable-stayed Bridge,it is necessary to determine a reasonable of the bridge state,the stress of the bridge is assigned to the target of this state.The Extradosed Cable-stayed is a multiple statically indeterminate structure.There are numerous internal forces in theory.The reasonable bridge state is an optimal solution that makes the internal force index of the bridge scientific and reasonable.This paper takes Chengnan Bridge in Yongzhou City as the research object,The model of the bridge was established through the space finite element software MIDAS CIVIL2015.At the same time,many scholars at home and abroad have been collected to study the reasonable bridge state of the Extradosed Cable-stayed Bridge,the advantages and disadvantages of various methods and their application scope are analyzed,finally,the reasonable state of Chengnan Bridge is determined by limiting the vertical displacement of cable and anchor point,bending moment and transverse displacement of the main tower,and all the mechanical indexes of the state of the bridge are scientific and reasonable.The Extradosed Cable-stayed Bridge also has the advantage that it is suitable for use in the restricted space height.Therefore,this paper takes Chengnan Bridge in Yongzhou City as an example to study the influence of different span on the internal force of the bridge tower.The effective tower height is taken as 15m,17m and 19m as the research object.The influence of different tower and span ratio on the internal force of the short tower cable-stayed bridge is studied and the conclusion is drawn that the internal force distribution of the bridge is more reasonable when the effective tower height is 17m.