Structural Parameters Study And Static Force Analysis Of Steel Trussed Arch Bridge

In recent years, scholars focus on the study of reinforced concrete arch bridge. As a new kind, the steel trussed bridge needs to be researched and analyzed including structure characteristic, mechanic properties and structural parameters’ influence on the structure. The results can be reference to the design and constructions of similar structural systems. The analysis below is based on a real project of a steel trussed arch bridge.The reasonable arch axis and the parameters that affect the structural internal force were introduced first. Through formula deduction, reasonable load distribution was discussed when the arch axial line type is parabolic curve or suspended chain curve. The study on arch axis of the steel trussed arch bridge is still not enough nowadays. The article discusses a method of searching a reasonable arch axis based on the finite element method. Through the adjustment of the discrete points of the arch axis, the deviation between the discrete points and the pressure line was minimized. The curve fitting was applied to gain smooth curve which is then the new arch axis. The article then discusses a method of curve fitting that is more adapting to the steel trussed arch bridge. To a complex structure as long-span steel trussed bridge, it is efficient to make good use of infinite element software to optimize the arch axis as the structure is such complex.Through finite element software, different structural parameters were analyzed. Firstly, the determination of structural boundary conditions which directly influence the structure which shall has totally different characteristics. The deformation and structural internal force are analyzed under two different boundary conditions. Secondly, the variety of internal force of arch foot and arch crown etc. will be analyzed while the rise-span ratio and arch axis change. The rise-span ratio will be changed by changing the vector height with certain step length. Thirdly, structural and mechanic characteristic of the bridge deck during the construction process will be studied. Effects and combined effects of actions including dead load, live load, wind load and temperature variation are analyzed. Based on the results above, we shall have deeper understanding of the steel trussed arch bridge.