Qto_ArchElementBaseQuantities Base quantities that are common to the definition of all occurrences of arch elements. IfcArchElement IfcArchElement Length The length of the object. The axis arch length from the profile center of gravity. Q_LENGTH Volume Volume of the element. Total volume of the arch element. Q_VOLUME CrossSectionArea The cross section area of the arch element. Q_AREA OuterSurfaceArea The outer surface area of the arch element. 0 InnerSurfaceArea The inner surface area of the arch element. 0