Editing Arch bridge (section)

===Construction sequence===
[[File:Limyra Bridge Workflow.gif|thumb|300px|Workflow on the Roman [[Limyra Bridge|Bridge at Limyra]]: the falsework was moved to another opening as soon as the lower arch rib had been completed ]]
[[File:Limyra Bridge Arch.svg|thumb|300px|The Roman segmental arch [[Bridge at Limyra]]]]

* Where the arches are founded in a watercourse bed (on piers or banks) the water is diverted so the gravel can first be excavated and replaced with a good footing (of strong material). From these, the foundation [[pier (architecture)|piers]] are erected/raised to the height of the intended base of the arches, a point known as the '''springing'''.
* Falsework [[centering]] (in British English: arch frame) is fabricated, typically from timbers and boards. Since each arch of a multi-arch bridge will impose a thrust upon its neighbors, it is necessary either that all arches of the bridge be raised at the same time, or that very wide piers be used. The thrust from the end arches is taken into the earth by substantial (vertical) footings at the canyon walls, or by large inclined planes forming in a sense ramps to the bridge, which may also be formed of arches.
* The several arches are (or single arch is) constructed over the centering. Once each basic '''arch barrel''' is constructed, the arches are (or arch is) stabilized with infill masonry above, which may be laid in horizontal [[running bond]] courses (layers). These may form two outer walls, known as the '''spandrels''', which are then infilled with appropriate loose material and rubble.
* The road is paved and [[parapet]] walls protectively confine traffic to the bridge.