Deflection Control Method Study of Long-Span PC Continuous Rigid-Frame Highway Bridge Compared with Railway Bridge
Down-deflection of long-span prestressed concrete (PC) continuous rigid-frame bridges in highway is more serious than in railway. Deflection comparison of highway bridges and railway bridges can provide a reference for the deflection control of highway bridges. Differences of highway and railway design codes about deflection were firstly analyzed. Then, the whole construction processes of a highway bridge and a similar span railway bridge were simulated by Midas/Civil. Both the stress state and long-term deformation were compared. The results show that stress states of the railway bridge will reduce the down-deflection. Finally, for highway bridges, we propose the compressive stress at upper edge of pier-top section should be slightly larger than that at lower edge during the layout of prestressed tendons.