Impact of Thermal Forces on Curved Bridge Bearings: A Comparative Study of Rigid and Elastic Link Configurations According to ASC Code Standards

For any bridge, the bearings are arranged such that the internal forces due to thermal, creep and shrinkage effects can be minimized in the deck. A typical bearing arrangement for the straight bridges, releasing all the constrained internal forces from the deck. The arrangement helps in the simplification and optimization of the deck design calculations. It is important to note that the expansion joints at the ends A and C shall accommodate the longitudinal displacements due to thermal, creep, and shrinkage considerations. Similarly, for the curved bridges, different types of bearing arrangements are possible based on the following criteria, (i) to minimize the internal forces in the bridge deck and the bearings, and (ii) to avoid the translation of the expansion joint across the traffic direction. The following are the bearing systems for the curved bridges, Radial bearing layout: The bearings are oriented such that the translation in the bearings is allowed radially with respect to the fixed bearing as shown in figure 4. This minimizes the internal forces in the bridge deck due to longitudinal actions (thermal, creep, and shrinkage effects) and reduces the bearing forces but the expansion joint at the abutment has translation along and across the traffic direction