# Inf. Surf Based LL/BR/CE \[CUG]

The effects of Live Load, Braking Load, and Centrifugal Load in OpenBrIM are calculated using the generated Influence Surfaces.

The defined roadway is considered the boundary for applying Live Loads and is further utilized for Influence Surface definitions.

To satisfy the requirements under extreme conditions, engineers must calculate the maximum and minimum reaction forces and moments at supports. To address such cases, Influence Surfaces are generated and used in the calculations of Live Load, Braking Load, and Centrifugal Load effects on the structure. After running the analysis for varying load locations, the user is presented with the following results:

1. Minimum/maximum force for selected Fenode/FELine/FESurface or composite elements.
2. Minimum/maximum stress for selected Fenode/FELine/FESurface or composite elements.

Such analyses are also supported for rails on OpenBrIM.

For a detailed explanation of each library object, refer to the relevant section of the documentation.


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