ence effectsРPrestressed concrete tends to be used for the longer-span bridge structures, which often means that they are built sequentially. As a result, the bending moments at the end of construction differ from those which would be expected if the bridge had been built in one go (the monolithic moment ). As an example, balanced cantilever construction builds out from a central pier, so the structure is inevitably in hogging bending throughout. When the tips of two cantilevers meet they are joined by an in-situ stitch, or sometimes by a short suspended span that is usually made fully continuous. The cantilever will have prestressing cables at the top to resist hogging bending, while continuity cables will be introduced across the joint to resist the sagging bending that will occur later.
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