Navigation:  Working With Beam Calculations > Beam Loads > Load Directionality and Components

The general sign convention used in Revit is opposite to that used in ENERCALC SEL.  In Revit, loads with a global downward direction use a negative magnitude.  ENERCALC for Revit converts these signs automatically between conventions during calculation launches to prevent any additional management burden on the user.  Users should use the normal directional convention appropriate to each individual program.

In conventional beam calculations that do not consider torsion or biaxial bending, loads that do not have a vertical component (Global Z in Revit) will be ignored during calculation launch.  

Loads that include horizontal components (i.e., Global X and Y in Revit) in addition to vertical will be included in the calculation, but only the vertical component will be used.

 

In addition to the cases discussed above, beam calculation launches also consider the presence of applied moments found in the Revit model.  These moments are modeled in Revit as point loads and then the moment magnitudes are set using the “Forces” and “Moments” fields in the native Revit Properties pane.

Similar to point loads with only force magnitudes, these moments are detected by proximity.  In order to ease the user’s workload in placing the moments and setting the magnitudes, the processing of moments into ENERCALC SEL uses a simplified approach.  Although Revit point moments are defined by global axis magnitudes in the Revit interface, it is NOT NECESSARY for the user to set components of the moment about each axis to ensure that the vector sum resultant acts about the proper local axis of the beam.  Instead, the components of the moment are taken to apply directly to the corresponding local axis of the same name:

•Revit parameter Mx would cause bending about the beam’s X-X axis in ENERCALC SEL

•Revit parameter My would cause bending about the beam’s Y-Y axis in ENERCALC SEL

•Revit parameter Mz will cause bending about the beam’s Z-Z axis in ENERCALC SEL

This means that in conventional beam calculations that do not consider torsion or biaxial bending, only Mx is of interest.  This also means that the visual / graphical orientation of the moment symbol relative to the beam in the Revit model does not control the directionality in the ENERCALC SEL calculation.

Note:  Both point loads and point moments are assigned to beams on a first-come / first-served basis.  Once a particular applied moment or load is automatically marked as having been associated to a particular beam calculation, it will not be eligible for inclusion in the launch of other calculations.  This prevents the forces effects from being accidentally double-applied.