Very short span bridges will often be most vulnerable to the damaging effects of excessive live loads, because their self weight is relatively low in relation to that of an axle load. This very short span UK highway bridge comprises an arch with several courses of brickwork rings.
In advance of performing an intrusive investigation, various scenarios were considered in LimitState:RING 2.0, including:
- assuming the rings were debonded and therefore acted separately and,
- assuming the mortar is sufficiently strong to ensure ring separation does not occur (as in a very short span structure inter-ring stresses will be low).
Short Single Span Bridge
Analysis using LimitState:RING 2.0 - (a) Debonded and (b) Bonded
Both the above mechanisms involve sliding failure (either circumferential or radial), something which is not identified using most other arch analysis software programs.