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UK Assessment Loading

To BD86/04 (UK)

Note this loading on constant width carriageways is best dealt with by specifying the design code in the Bridge Loading Analysis Specification dialog when paths and loading will be generated automatically. For varying width carriageways or local analysis where the loaded area under individual wheels is important the following components are available:

Vehicles​

NOTES: See BD86 for details of vehicles, Dynamic Factor has been included in axle load definition. Slow speed vehicles have lower axle loads but smaller exclusion lengths. Overload factor, OF, has been applied to a particular axle in these vehicles, this can be slightly unconservative since BD requires factor to be applied to the most onerous axle.

  • SV-TT-Norm-ToHighChain – Normal speed travelling in direction of increasing chainage
  • SV-TT-Norm-ToLowChain – Normal speed travelling in direction of decreasing chainage
  • SV-TT-Slow-ToHighChain – Slow speed travelling in direction of increasing chainage
  • SV-TT-Slow-ToLowChain – Slow speed travelling in direction of decreasing chainage
  • SV-Train-1.2ToHighChain – Normal speed travelling in direction of increasing chainage, 1.2m between trailer axle groups
  • SV-Train-1.2ToLowChain – Normal speed travelling in direction of decreasing chainage, 1.2m between trailer axle groups
  • SV-Train-5ToHighChain – Normal speed travelling in direction of increasing chainage, 5m between trailer axle groups
  • SV-Train-5ToLowChain – SV-Train-9ToHighChain, SV-Train-9ToLowChain
  • SV150-1.2Norm, SV150-1.2Slow, SV150-5Norm, SV150-5Slow, SV150-9Norm, SV150-9Slow
  • SV100-1.2Norm, SV100-1.2Slow, SV100-5Norm, SV100-5Slow, SV100-9Norm, SV100-9Slow
  • SV80-1.2Norm, SV80-1.2Slow, SV80-5Norm, SV80-5Slow, SV80-9Norm, SV80-9Slow

VUDL​

  • HA (UK) – full HA loading to BD37
  • Foot (UK) – full footway loading on a 1m strip to BD37

Path Loading​

NOTES: These loadings select the most onerous of the vehicles listed, regardless of traffic direction. HA + loadings include full HA(UK) Loading and should have VUDL factored to suit BD21 lane factors. Because ULS factor on SV vehicles is 1.1 while on HA loading it is 1.3 an additional factor is needed to account for this (in full carriageway optimization the SV vehicle loading is factored by 1.11.3\frac{1.1}{1.3}). Exclusion lengths are measured from end axles and are 25 m for normal vehicles and 5m for slow vehicles.

  • SV-TT, HA + SV-TT – SV-TT-Norm-ToHighChain, SV-TT-Norm-ToLowChain, SV-TT-Slow-ToHighChain, SV-TT-Slow-ToLowChain
  • SV-Train, HA + SV-Train – SV-Train-1.2ToHighChain, SV-Train-1.2ToLowChain, SV-Train-5ToHighChain, SV-Train-5ToLowChain, SV-Train-9ToHighChain, SV-Train-9ToLowChain.
  • SV-150, HA + SV-150 – SV150-1.2Norm, SV150-1.2Slow, SV150-5Norm, SV150-5Slow, SV150-9Norm, SV150-9Slow
  • SV100, HA + SV-100 – SV100-1.2Norm, SV100-1.2Slow, SV100-5Norm, SV100-5Slow, SV100-9Norm, SV100-9Slow
  • SV-80, HA + SV-80 – SV80-1.2Norm, SV80-1.2Slow, SV80-5Norm, SV80-5Slow, SV80-9Norm, SV80-9Slow

These loads should normally be applied to Lane Paths between 2.5m and 3.65m wide. Where lanes are less than 3.5m wide then the SV vehicles do not fit entirely within a single lane. In this case vehicle paths can be used to place the vehicle eccentrically, Shadow HB + HA loading placed on the lane paths will approximate to lane loading in this case, but will not give correct exclusion lengths.