Study On The Static And Dynamic Characteristics Of Flexible Suspension Bridge

The flexible suspension bridge because of stress concise,convenient construction,large span capacity,flexible suspension bridge has become the common bridge area,hilly area.She is different from the highway suspension bridge,the biggest feature is no beam or girder is very short,with the increase of the span of the constant load does not significantly increase,while accounting for live load the increasing proportion of large span after even more than the constant load.So the structure characteristics of the bridge is very low in the whole stiffness,relative stiffness of large beam bridge,arch bridge is soft,commonly used as a pedestrian bridge,the static and dynamic aspects of the characteristics of relative highway suspension bridge is not entirely consistent.Our country has not issued the relevant soft The specification of the suspension bridge,which makes many key problems during design and construction,no basis to follow,such as wind cable is applied if necessary,and the optimal arrangement of wind cable tension in reasonable size,rise span ratio,the flexible suspension bridge deck width,other specifications or empirically determined with reference to the span range only.This paper takes Chongqing Yubei cave No.2 pedestrian suspension bridge as the basis,using MATLAB and Midas software,ANSYS finite element software for flexible suspension bridge static and dynamic characteristics are analyzed,the main work is as follows:1.The static calculation theory of suspension bridge is reviewed,and the static analysis is carried out by Midas on the Guanyindong Bridge.2.The calculation formula of cable parabola and segmental catenary,according to the segmental catenary method to write linear solver of main cable of suspension bridge can be calculated by MATLAB software,the main cable bridge alignment,unstressed length,pre bias of cable saddle,fixed length of main cable saddles,saddle point coordinates etc.,and through the verification procedures and comparison determine its correctness.3.The dynamic characteristics of the bridge are analyzed by means of ANSYS modeling,and then the influence of different span,bridge width,bridge deck form,span ratio and other factors on the dynamic characteristics of the bridge is compared.4.the necessary conditions for the establishment of the wind resistance cable are determined,and the best form of the wind resistant cable is determined by the ANSYSmodeling and analysis by changing the horizontal angle between the wind cable and the bridge deck,the vertical angle,the tensile force and the anchor position of the main beam.5.ANSYS is used to analyze the transient load,and the effect of different bridge width and wind resistance on the dynamic response of pedestrian load is compared.6.The limit span of the flexible suspension bridge with longitudinal and transverse beams is discussed,and the range of the ratio of span to span and the ratio of span to span are studied,which provides a reference for the tension of the cable.