3. Pre-stressed concrete cantilever bridges

The very frequent use of the corbelled construction method testifies to the many advantages of this method, which eliminates the need for bending or scaffolding. In the most common cases, this involves building a bridge deck in sections from the piers: once a section, called a "voussoir", has been built, it is attached to the section already built, using prestressing. The section then becomes self-supporting, enabling the resources needed to build the next section to be deployed. Once all the sections have been completed, the result is what is known as a flail (figure 5 ).