Leveling pad for bridge bearing
Leveling pad used at below, and above of bridge bearing as shown in figure 1. during the casting of a pier, voids are formed using PVC pile. Number and orientation of this voids should be identical to bridge bearing studs, the surface of piers, including this voids, will be prepared and roughen. Then bearing placed above pier, center line, level of bearing and presetting should be checked and confirmed that it matching approved drawing, then we install shutter around bearing and pour the grout, the purpose of leveling pad is to provide a good bonding between bridge bearing and pier also to ensure that the bearing installed in correct location and level.
A leveling pad introduced at the bottom of the superstructure, as shown in figure 1, to fulfill many requirements. This leveling pad will allow for the leveling of bearing horizontally to avoid inducing eccentricities on a substructure. The superstructure will not lie horizontally for many reasons, in general, there will be slope and change in grade in the longitudinal and transverse direction. Figure 1 showing a bridge with superelevation, attaching bridge bearing directly to superstructure will induce stress on bridge bearing and piers due to change in bridge level and gradient, leveling pad formed directly in superstructure soffit as shown in figure 3, leveling pad will have a wedged shape for better concrete mobility at the bridge bearings.