6. Conclusion

Sizing the bearings of bridges crossing inland waterways to withstand impact is a problem that can generally be solved. However, when crossing estuaries or linking islands, the problem of bearing resistance is always very difficult to solve. If the planned structure is very long, it is hardly possible to envisage any kind of protection around each pier, which would be very costly to build and maintain. This is why, in general, the structure is designed with a partial possibility of destruction. For example, a static "console" design allows only the section carried by the pier and the two adjacent independent spans to fall, without the risk of chain reaction propagation of the entire deck (presence of "fuses").

Such a device proved its effectiveness when a pier broke on the Maracaibo bridge (figure