Probably not really an exporter issue, but rather a historically Revit-evergreen-issue.
When Revit is regenerating the export options mapping table, it will list the non existing EntityClass "IfcReinforcementMesh". Probably an idea to get it once corrected into "IfcReinforcingMesh"?

 

Last edit: Dirk Van Rillaer 2018-07-10