The Three Main Girder Continuous Steel Truss Arch Bridge As A Whole Node Stress Distribution And Tectonic

Dong Ping Bridge is a three trusses continuous steel arch bridge with the main span of 99+242+99m. The arrangement of three trusses is identical. In the position of truss joint, integral type joint has been adopted, which connects with other truss members in external part of joint. Because of the complicated joint structure, the present thesis gives an analysis of stress distribution of this integral joint. The main results of this thesis are presented as follows:1. On the basis of finite element analysis software MIDAS, three-dimension model of tri-truss continuous steel arch bridge has been established. The force performance of main truss members in Dong Ping Bridge has been studied under three construction stages, which are dead load, dead + live load, and dead + live + horizontal wind load. In this way, weakened point under the stress has been settled through stress analysis and its distribution.2. The thesis investigates the stress analysis under elastic-stage and transmission characteristics of three mainly joints in middle truss(ME6 in side span, MG9 middle fulcrum position and ME11 in the intersection point between stiffening chord of middle span and lower chord)has been studied. The result of the study provides a basis and reference for the design of Dong Ping Bridge.3. On the basis of overall and local analysis results, stress of joint members and stress inside the joint has been compared. Non-uniform coefficient of member ends has been possessed. It provides a basis and reference for design of other members.4. On the basis of stress concentration in the components, construction technology as well as structural method has been provided. Moreover, the suggestion for excessive stress phenomenon in joint has been proposed.