In this thesis, various parametric study on the cross beam is performed to show the prevailing over-design of the PC beam bridge. The span length is fixed to 30m for simplicity, because the length is widely used in common PC beam bridge in Korea. FEM is used to analyze the PC beam bridge, which is more reasonable than any other bridge analytic schemes.
Parameters included in this paper can be classified into two categories. The first one is skew angle of the deck, 90°, 60°, 45° respectively. The second one is the number of cross beam used in one span, 7, 5, 3, respectively. The slab is modeled using shell elements with drilling degrees of freedom, which is very effective for connecting shell with beam. The shell and eccentric beam modeling is described for the effective idealization of slab-on-girder bridge.
Under the aforementioned conditions, the maximum values of bending, shear and torsional member forces are calculated, all of which meet recommendations in the specifications. It is concluded that cross beams are over-designed in PC beam bridge with span length of 30m. It might be recommended for bridge designers to reduce the number of cross beams.
