Suitability assessment of the traditional unified railway bridge girders for high-speed traffic

The article deals with the parameters of high-speed trains effect on the unified simple-span girder reinforced concrete bridge superstructures on conventional railways using a simplified methodology of determining maximum vertical accelerations and live load dynamic factors. It is noted that the dynamic additions to the stress-strain behavior components (bending moments, transverse force and vertical sags) differ from each other. The presented methodology of dynamic factors determination helps to make a dynamic calculation and to identify general forces in simple-span girder superstructures without numerical simulation and straightforward dynamic analysis, which greatly reduces labor intensity of the design works. Based on the dynamic calculation results, a conclusion is made that the unified simple-span girder reinforced concrete bridge superstructures can be applied on high-speed railways, and the scope of their application is specified.