The Design Method Of Ballast Deck Simply Supported Steel Truss Railway Bridge

As the high-speed train opened up as well as the living standard of people increasingly prompted, it is a trend to adopt ballast as the bridge deck in simply supported steel truss bridges so as to diminish the vibration when trains passing through bridges, to abate the noise pollution for environment and to improve sense of comfortability. However, it is rarely been seen the construction of ballast deck simply supported steel truss bridges also some technical issues would be solved in design realms.Based on special structure and mechanical characteristics, some design researches have done in ballast deck simply supported steel truss railway bridges. This thesis firstly focus on simplification algorithm, Spatial structure analysis method, fatigue calculation theory, Train-line-bridge system coupling basic theory as well as the design method of ballast deck simply supported steel truss railway bridge. Taking ShaPing River Bridge in 1 to 64 meters of the ballast deck, which is a reconstruction project Litang to Qinzhou segment of Guangxi coastal railway as a background program, this paper then mainly study on main girder clear size, main component size, main girder geometry, structure material, joint mode and deck design, coming with the construction of a calculation mode, which considered design load and combination patterns. Last part of this dissertation mainly calculated internal force of each bar, also checked high strength bolt connection, structure stability calculation and structure fatigue. The Mainly conclusions are as follows:(1) A mode for calculating plane truss structure and space beam element structure were established, individually calculated internal force and compared the result. The result shows that different calculation method lead to different result, which different bar had an diverse error discretization. Except for end diagonals slightly small, The result of axial force that other rode calculated, which adopted plane truss structure calculation model is greater than that of which adopted space beam element structure calculation model. The result that employed plane truss structure calculation model is somewhat safe.(2) Fatigue design load combination method for checking is summed up, following a processes of bar fatigue checking.(3) Construction drawing design of ShaPing River Bridge is accomplished. (4) The design method and processes of ballast deck simply supported steel truss railway bridge are summarized.